PLASMA/IONIC REACTOR FOR PROCESSING BIOSOLIDS MATERIALS

Abstract

A method of processing a material comprising: receiving an input material to be processed within a reaction chamber, the input material comprising a biosolids material; energizing one or more sets of electrodes, each set of electrodes including an anode electrode and a cathode electrode, each anode electrode and cathode electrode having an electrode tip exposed to the reaction chamber; and creating an electrical arc between the anode electrode tip and the cathode electrode tip within the reaction chamber to subject at least some of the input material to electrical arcing, thereby reacting at least a portion of the biosolids material and forming a processed material comprising hydrogen (H.sub.2) and carbon monoxide (CO).

Claims

1. A method of processing a material, the method comprising: receiving an input material to be processed within a reaction chamber, the input material comprising a biosolids material; energizing one or more sets of electrodes, each set of electrodes including an anode electrode and a cathode electrode, each anode electrode and cathode electrode having an electrode tip exposed to the reaction chamber; and creating an electrical arc between the anode electrode tip and the cathode electrode tip within the reaction chamber to subject at least some of the input material to electrical arcing, thereby reacting at least a portion of the biosolids material and forming a processed material comprising hydrogen (H.sub.2) and carbon monoxide (CO).

2. The method of claim 1, further comprising: creating a plasma in a plasma torch; and injecting the plasma from the plasma torch into the reaction chamber to expose at least some of the input material to the plasma from the plasma torch when forming the processed material.

3. The method of claim 1, wherein the biosolids material is in the form of dried biosolids particles.

4. The method of claim 3, wherein the biosolids particles have an average particle size in a range of about 0.3 mm to about 4.0 mm.

5. The method of claim 3, wherein the biosolids particles have an average particle size in a range of about 0.5 mm to about 2.0 mm.

6. The method of claim 1, further comprising drying the biosolids material prior to feeding the input material to the reaction chamber.

7. The method of claim 1, wherein the biosolids material has a water content of not more than 20 wt. %.

8. The method of claim 1, further comprising: feeding the processed material to a water-gas shift reactor.

9. The method of claim 1, wherein the biosolids material has a water content of at least 20 wt. %.

10. The method of claim 9, wherein the processed material is not further treated in a water-gas shift reactor.

11. The method of claim 1, wherein the biosolids material comprises undigested biosolids.

12. The method of claim 1, wherein the biosolids material comprises digested biosolids.

13. The method of claim 1, wherein the biosolids material comprises: 5 wt. % to 95 wt. % digested biosolids relative to total biosolids; and 5 wt. % to 95 wt. % undigested biosolids relative to total biosolids.

14. The method of claim 1, comprising feeding a working gas to the reaction chamber.

15. The method of claim 1, comprising feeding a reactive gas to the reaction chamber.

16. The method of claim 15, wherein the reactive gas comprises one or more oxygen atoms.

17. The method of claim 15, wherein the reactive gas is selected from the group consisting of air, oxygen gas, water, carbon dioxide, nitrogen oxides, and combinations thereof.

18. The method of claim 15, wherein the reactive gas comprises oxygen gas.

19. The method of claim 15, wherein the reactive gas comprises water.

20. The method of claim 15, wherein the reactive gas comprises carbon dioxide.

21. The method of claim 15, wherein the reactive gas comprises one or more nitrogen oxides.

22. The method of claim 15, wherein the reactive gas comprises air.

23. The method of claim 1, comprising operating the reaction chamber in an oxidative process mode.

24. The method of claim 1, comprising operating the reaction chamber in a pyrolysis process mode.

25. The method of claim 1, comprising supplying power to the electrodes in an amount in a range of 0.5 (kW.Math.hr)/kg to 4 (kW.Math.hr)/kg relative to biosolids feed rate.

26. The method of claim 1, wherein creating the electrical arc comprises forming a localized plasma in the reaction chamber having a temperature of at least 3000 C. to which the input material is subjected.

27. The method of claim 1, wherein creating the electrical arc comprises operating the reaction chamber at about atmospheric pressure.

28. The method of claim 1, wherein the processed material comprises a gas phase containing 25-60% hydrogen gas (H.sub.2) and 20-50% carbon monoxide (CO).

29. The method of claim 28, wherein the gas phase further comprises at least one of water (H.sub.2O) and carbon dioxide (CO.sub.2) in an amount up to 2%.

30. The method of claim 28, wherein the gas phase further comprises nitrogen (N.sub.2) in an amount that is at least 80% of the gas phase that is other than H.sub.2, CO, CO.sub.2, and H.sub.2O.

31. The method of claim 28, wherein a ratio of hydrogen gas:carbon monoxide in the gas phase is in a range of 2:1 to 1:1.

32. The method of claim 1, comprising reacting the biosolids material with a carbon conversion of at least 40%.

33. The method of claim 1, comprising reacting the biosolids material with a carbon conversion of at least 90%.

34. The method of claim 1, wherein the processed material comprises nanoparticles selected from the group consisting of nanosized ash, carbon nanoparticles, and combinations thereof.

35. The method of claim 34, wherein the nanoparticles have an average particle size in a range of about 5 nm to about 100 nm.

36. The method of claim 1, wherein the processed material is free from tar.

37. The method of claim 1, comprising processing the material in a continuous process operation.

38. The method of claim 1, comprising processing the material in a batch process operation.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] FIG. 1 is a front view of an exemplary embodiment of a plasma or ionic gasifier apparatus containing multiple plasma units stacked next to each other to form a reaction chamber.

[0017] FIG. 2 is a selectively cross-sectioned top view of a plasma or ionic unit used in the exemplary embodiment of a plasma gasifier apparatus of FIG. 1.

[0018] FIG. 3 is a fragmented perspective view of a plasma unit used in the exemplary embodiment of a plasma gasifier apparatus of FIG. 1.

[0019] FIG. 4 illustrates a cross-sectional view of an example electrode assembly that may be used within the plasma gasifier of FIG. 1.

[0020] FIG. 5 illustrates a first configuration for a tubular support jacket within the electrode assembly of FIG. 4.

[0021] FIG. 6 shows a second configuration for a tubular support jacket within the electrode assembly of FIG. 4.

[0022] FIG. 7 is a schematic illustrating a plasma module with a hybrid plasma jet and plasma arc system in a vertical configuration.

[0023] FIG. 8 is a perspective and partially cut-away view of a hybrid plasma or ionic reactor having a plasma reactor similar to that of FIG. 1 and including a plasma torch disposed vertically at the top of the plasma reactor.

[0024] FIG. 9 is a schematic illustrating a plasma module with a hybrid plasma jet and plasma arc system in a lateral configuration with (A) one plasma torch or (B) two plasma torches.

[0025] FIG. 10 is a top view schematic of a plasma unit of the gasifier of FIG. 1, including a first offset electrode arrangement.

[0026] FIG. 11 is a top view schematic of a plasma unit of the gasifier of FIG. 1, including a second offset electrode arrangement.

[0027] FIG. 12 is a top view schematic of a plasma unit of the gasifier of FIG. 1, including a third offset electrode arrangement.

[0028] FIG. 13 is a top view schematic of a plasma unit of the gasifier of FIG. 1, including a fourth offset electrode arrangement.

[0029] FIG. 14 is a top view schematic of a plasma unit of the gasifier of FIG. 1, including a fifth offset electrode arrangement.

[0030] FIG. 15 depicts a first set of test results for cracking methane using a plasma gasifier with the plasma unit of FIG. 10.

[0031] FIG. 16 depicts a second set of test results for cracking methane using a plasma gasifier with the plasma unit of FIG. 10.

[0032] FIG. 17 depicts a schematic illustrating a simple plasma module or unit with a single set of arc electrodes which are configured to introduce a working gas having a vortex into a cylindrical reaction chamber.

[0033] FIG. 18 depicts a schematic showing a first exemplary embodiment of a plasma arc system in cross-section having groves formed on an outside surface of an arc electrode to induce a vortex in a working gas introduced into a reaction chamber.

[0034] FIG. 19 depicts a schematic illustrating a second exemplary embodiment of a plasma arc system in cross-section having groves formed on an inside surface of an arc electrode body to induce a vortex in a working gas introduced into a reaction chamber.

DETAILED DESCRIPTION

[0035] FIGS. 1-3 illustrate a basic plasma or ionic gasifier 10 in which the improvements described herein may be implemented to make the plasma or ionic gasifier 10 more efficient and/or perform better material processing and/or to make the gasifier 10 applicable for the processing of a wide range of materials or uses. Referring to FIG. 1, the plasma or ionic gasifier apparatus 10 processes an input material 12 introduced at an input 13 of the gasifier 10 to produce an output material 14 emitted from an output 15 of the gasifier 10. The output material 14 may be, for example, a synthesis gas and/or other materials as described herein. As illustrated in FIG. 1, the plasma gasifier 10 contains one or more circular plasma units 16 that are stacked in tandem with respect to one another (i.e., aligned along a longitudinal axis through the center of each unit 16), with each plasma unit 16 being formed from a circularly (in cross section) shaped outer ring with a cylindrical interior space defined in the middle of the outer ring. This interior space makes up a plasma or reaction zone 18 within the gasifier 10. Still further, each plasma unit 16 has one or more sets of electrodes 20 extending through the outer wall thereof and into the reaction chamber 18. Each set of electrodes 20 includes an anode electrode and a cathode electrode that extend radially towards the center of the plasma unit 16. Each set of electrodes 20 is coupled to a working gas supply 22, a coolant supply 24 and a power supply 26 by various applicable conducts or electrical connectors. Generally speaking, the working gas supply 22 provides a working gas to each electrode 20, and this gas is transported through and emitted from the electrode, as described in more detail herein, into the reaction chamber 18. This working gas helps cool the electrode tips of the electrodes 20 and, additionally, is subject to high electric fields and arcing created by the electrodes 20 within the reaction chamber 18 and, as a result, ionizes to create plasma within the reaction chamber 18. The coolant supply 24 provides coolant to the electrodes 20 to help assist in keeping the electrodes 20 from overheating during use. This coolant may be recycled and cooled in the coolant supply 24 to create a closed coolant loop. Additionally, the coolant for each electrode assembly 20 may be supplied via a high-pressure pump. After cooling the electrode or an electrode tip as described in more detail herein, the coolant exits the electrode assembly 20 and may be stored in a reservoir, not shown. When fresh water is available, the coolant in the reservoir may be kept cold by a cooling unit, not shown, such as a portable water heat exchanger. In another embodiment, when fresh water is not available, the cooling unit can be a chemical-based chiller or any other cooling unit.

[0036] Still further, the power supply 26 provides electrical power to the electrodes at sufficient power (e.g., voltage and current) to create arcing between the anode and cathode of each electrode pair 20. The power supply 26 may be an AC power supply which may provide, for example, one phase or three phase AC power to the electrodes 20 or may be a DC power supply. A separate power supply 26 may be provided for each set or pair of electrodes 20 or a combined power supply may provide power to multipole electrode pairs 20. However, the power signal sent to each pair of electrodes 20 may be electrically isolated from the power signals sent to the other pairs or sets of electrodes 20. Still further, the electrode assemblies 20 may be connected to the power supply 26 through water-cooled cables, which provide both the cooling and current paths for the electrode assemblies 20.

[0037] Although one plasma unit 16 can be used, performance may be optimized through the use of a plurality of plasma units 16 stacked on top of or next to one another so that the outer walls or rings align longitudinally. For example, in FIG. 1, the plasma gasifier 10 is illustrated as including four stacked plasma units 16 creating an elongated tubular or cylindrical reaction zone 18. It should be understood, however, that the plasma gasifier 10 can have any number or plurality of stacked plasma units 16, including only one. By stacking the plasma units 16, the plasma or reaction zone 18 is lengthened along the longitudinal axis of the gasifier 10, and this elongated space or reaction chamber 18 enables the processing time for the incoming material 12 introduced into the reaction chamber 18 of the plasma gasifier 10 to be extended or increased, as the incoming material 12 flows in sequence through each of the different plasma units 16 when traveling from the input 13 to the output 15 of the gasifier 10. Moreover, the modular configuration created by stacking multiple plasma units 16 next to (e.g., on top of) one another enables an operator to manipulate the power settings in each of the plasma units 16, e.g., in the electrodes 20, separately to achieve an overall temperature profile for the plasma gasifier 10. An operator or designer can also add or subtract modular plasma units 16 to achieve the desired residence time for complete gasification of a particular class of incoming material 12.

[0038] As illustrated more clearly in FIG. 2, which depicts a transverse view of one of the plasma units 16 of FIG. 1, each plasma unit 16 has an annular body 28 with an inner wall 30 and an outer wall 32. The inner wall 30 defines a central plasma zone or reaction chamber 34 (e.g., making up part of the reaction chamber 18 of FIG. 1). The inner wall 30 is refractory and so is capable of containing the heat of the plasma without significant degradation. A preferred material for the inner wall 30 is graphite. However, certain refractory ceramics can also be used. A gap space 36 exists between the inner wall 30 and the outer wall 32. The gap space 36 is packed with insulation 38, such as high temperature ceramic fibers. In one embodiment, the insulation 38 (e.g. the ceramic fibers) may be, but is not limited to, Zirconia fibers. Alternatively, and/or additionally, granulated sand and/or granulated oxide materials can be used as the insulation 38. Ceramic fibers or granulated oxide materials have significant advantages over conventional solid high-density blocky oxide insulations as granulated oxides and/or ceramic fiber blankets make up very low-density packing materials having significant voids therein. These voids have very low thermal conductivity and have excellent thermal insulation properties. Very low-density thermal insulation materials also reduce the overall weight of the gasifier 10.

[0039] In any event, the annular bodies 28 and the central plasma zones 34 concentrically align when the plasma units 16 are stacked. Moreover, the central plasma zone 34 of each plasma unit 16 is accessible through a plurality of access ports 40. Preferably, each plasma unit 16 contains at least eight access ports 40 but any other number of access ports could be used including more or less access ports 40. Each of the access ports 40 is lined with a sleeve of refractory material, such as a ceramic material, that can maintain integrity in the heat field of plasma created in the reaction chamber 34. Moreover, each access port 40 may be used to insert or hold an electrode 42 therein. As such, it is preferable to have at least two access ports 40 in each plasma unit 16 and to provide for an even number of access ports 40, although this is not strictly necessary. Moreover, one or more of the access ports 40 may be used to store or insert a sensor of some sort to provide measurements or viewing of the reactions within the reaction chamber 34.

[0040] Most of the access ports 40 in each of the plasma units 16 receive electrodes or electrodes assemblies 42. Each of the electrode assemblies 42 is surrounded by an insulator that is sized to pass into the access ports 40 with tight tolerances. The tolerances prevent any significant gaps from existing between the insulator and the interior of the access port 40 that can leak plasma out of the plasma gasifier 10. As will later be explained in more detail, each of the electrode assemblies 42 includes an electrode tip 46 and a gas conduit 47 (illustrated in dotted relief in one electrode 42 of FIG. 2). The electrode tip 46 extends into the central plasma zone 34 and creates an arc with another electrode tip 46 during operation. The gas conduit 47 introduces a working gas from the working gas supply 22 of FIG. 1 into the plasma or reaction zone 34, which working gas is converted into plasma by the arc created between the tips 46 of two electrodes. Each of the electrode assemblies 42 is cooled by a coolant from the coolant supply 24 of FIG. 1. Moreover, it will be understood that each of the electrode assemblies 42 is coupled to the power supply 26 of FIG. 1 to receive electrical power (voltage and current).

[0041] Generally speaking, each plasma unit 16 receives the electrode assemblies 42 in sets of two. As such, each plasma unit 16 can receive two, four, six, eight or more of the electrode assemblies 42, depending upon the number of access ports 40 present. The electrodes of a first set of electrode assemblies 42 are set at a first position P1 and a second position P2 on opposite sides of the central plasma zone or reaction chamber 34. Likewise, the electrodes of a second set of electrode assemblies 42 are set at positions P3 and P4 and the electrodes of a third set of electrode assemblies 42 are set at positions P5 and P6. Accordingly, in the example of FIG. 2, there are three sets of electrode assemblies 42 and each of the set of electrode assemblies 42 includes one anode electrode and one cathode electrode. However, any other number of sets of electrode assemblies 42 could be used on each plasma unit 16, including one set, two sets, four sets, etc.

[0042] The positions P1, P2 of the first set of electrode assemblies 42 are disposed radially or circumferentially with respect to the positions P3, P4 of the second set of electrode assemblies 42 and with respect to the positions P5, P6 of the third set of electrode assemblies 42 within each plasma unit 16. The angle of separation between the electrode assemblies 42 of the second set and the electrode assemblies 42 of the third set is illustrated in FIGS. 1 and 2 as being 90 degrees. The angle of separation between the electrode assemblies 42 of the first set and the electrode assemblies 42 of the second set is illustrated as 45 degrees. Moreover, the angle of separation between the electrode assemblies 42 of the first set and the third set is also 45 degrees. However, these are but examples and other angles of separation between different sets of electrode assemblies could be used.

[0043] FIG. 3 illustrates one example of the configuration of the electrode assemblies 42 connected to mechanical motivators or actuators for reciprocally moving the electrodes 42 or the electrode tips 46 of the electrodes 42 radially into and out of the reaction chamber 34 while the electrode assemblies 42 are disposed in the access ports 40. The reciprocal movements are controlled by a corresponding linear actuator 48 that attaches to each of the electrode assemblies 42. Each set of electrode assemblies 42 can be moved synchronously to or independent of each other. In a single plasma unit 16, the separation (arc gap) between any set of electrode assemblies 42 can be adjusted by moving those electrode assemblies 42 into, or out of, the access ports 40.

[0044] In the exemplary embodiment of FIGS. 1-3, three sets of electrode assemblies 42 are inserted into each plasma unit 16 through the access ports 40. Preferably, in this case, one or both of the remaining access ports 40 are used for observations of the plasma gasifier 10 in operation, such as to hold sensors of some kind or another (e.g., temperature sensors, pressure sensors, video cameras, etc.). Of course, electrode assemblies 42 attach to (are inserted into) the access ports 40 that are not being used for observation. Moreover, as illustrated in FIG. 3, each of the electrode assemblies 42 has the linear actuator 48 that controls the movements of the electrode assemblies 42 into and out of the access ports 40 and each linear actuator 48 may be connected to a control mechanism or controller that enables a user to control the movement of the electrode assemblies 42 during use. The mechanical or linear actuators 48 may be electrical actuators, hydraulic actuators, or any other desired type of mechanical or linear actuators.

[0045] During operation, one or more arcs can be ignited between the cathode and the anode of each pair of electrodes by (i) a high voltage discharge, (ii) a high frequency discharge, or by (iii) touching and withdrawing one electrode set from each other. When a high voltage or high frequency discharge is used to ignite an arc, the electrode tips 46 of a set of electrodes 42 are brought in close proximity to each other such as by operation of the actuators 48. After the power supply 26 that supports the electrode assembly 42 in question is energized, a high voltage or high frequency discharge is applied across the central plasma zone 34 between electrode tips 46, which ignites an arc.

[0046] In a touch and withdrawal method of igniting an arc, the anode and cathode electrode tips 46 from a particular set of electrode assemblies 42 are brought into contact with each other momentarily after the associated power supply 26 is energized. As soon as a spark is generated, the electrode assemblies 42 are drawn apart quickly and an arc is ignited. Moreover, after a first arc is ignited, a second set of electrode assemblies 42 may be moved into the first arc region for ignition. The second set of electrode assemblies 42 may require thermal conditioning for a few seconds in the arc before it is self-ignited. In particular, thermal conditioning may be required to heat the electrode tips 46 to a sufficient temperature for thermionic emission of electrons to occur. Different plasma units 16 in the same plasma gasifier 10 can be used to form a combined arc system. In this configuration, arc systems complement each other in heating the combined plasma to achieve a much higher energy state than is possible using a single plasma unit 16. Additional plasma units 16 in the plasma gasifier 10 can be ignited in the same way.

[0047] As will be understood, the use of a plasma gasifier 10 with two or more plasma units 16 can generate very large and significantly high temperature arcs within the common plasma zone or reaction chamber 34 using relatively low input power from each participating plasma unit 16. Moreover, the plasma units 16 can be duplicated and stacked onto one other. In this manner, when one or more plasma units 16 sustain arcs there is a field free (absence of current and voltage) high-energy plasma tail flame that can flow into other plasma units 16. In this case, the electrode assemblies 42 in the other plasma units 16 superimpose discharges in the tail flame and reignite it back into an arc state so that the stacked plasma units 16 produce a very large plasma column with very significant energy content. The modular stacking configuration of plasma units 16 can operate so that a field free (current and voltage free) plasma flame from the upstream unit is reheated to a field active (current and voltage active) arc state by superimposing an electric discharge in the downstream plasma units 16. The net plasma energy flow from one plasma unit 16 to another is called energy cascading, which adds energy to the downstream plasma units 16 and allows the downstream plasma units 16 to operate with a lower energy requirement.

[0048] FIG. 4 illustrates an example electrode assembly 42 that may be used in the gasifier 10 described herein. In particular, the electrode assembly 42 includes an electrode tip 46. The electrode tip 46 extends into the central plasma zone or reaction chamber 34 and creates an arc with another electrode tip 46 from a different electrode assembly 42 (not shown in FIG. 4). Each of the electrode assemblies 42 is preferably made of a tungsten, a tungsten alloy, or some other high-temperature conductive material(s). The electrode tip 46 is mounted to the end of a tubular support jacket 49, which is highly conductive and has a first end 49A and an opposite second end 49B. The second end 49B of the tubular support jacket 49 terminates with the electrode tip 46, wherein the electrode tip 46 seals the second end 49B or is directly mounted to a sealed second end 49B. The opposite first end 49A of the tubular support jacket 49 is coupled to an electrode base 50 which is connected to the electrical power supply 26 (FIG. 1), wherein the electrode base 50 receives current from the power supply 26. Any current received at the electrode base 50, travels through the electrode base 50 and into the tubular support jacket 49. The current then flows through the material of the tubular support jacket 49 and into the electrode tip 46.

[0049] The tubular support jacket 49 defines an internal compartment or space 51. The coolant from the coolant supply 24 (FIG. 1) is introduced into the internal compartment 51 through a supply tube 52. The supply tube 52 has a dispensing end 52A that terminates in the internal compartment 51 just short of the electrode tip 46. This configuration produces a small gap 54 of, for example, five millimeters between the dispensing end 52A of the supply tube 52 and the electrode tip 46. In this manner, any coolant pumped through the supply tube 52 will impinge directly upon the electrode tip 46, therein directly actively cooling the electrode tip 46.

[0050] The supply tube 52 has a smaller outside diameter than the inside diameter of the internal compartment 51. As a consequence, a drain gap 56 exists between the interior of the tubular support jacket 49 and the exterior of the supply tube 52. This drain gap 56 receives the coolant after the coolant is pumped against the electrode tip 46. The draining coolant is directed back into the electrode base 50, which includes one or more conduits 58 that channel the coolant into a coolant outlet. The coolant may surround at least some parts of a power cable 62 that leads from the power supply 26 (FIG. 1). In this manner, the coolant can also actively cool the power cable 62. Thus, the flow of the coolant into and out of the internal compartment 51 of the tubular support jacket 49 directly cools the electrode tip 46 and the tubular support jacket 49 during operation as well as the power cable 62.

[0051] An insulator construct 64, which includes an insulation base 66, an elongated insulation tube 68 and a protective insulation cap 70, surrounds the tubular support jacket 49. The insulation cap 70 is annular and defines a central opening 72. The tubular support jacket 49 extends through the central opening 72 in the insulation cap 70, therein supporting the electrode tip 46 just ahead of the insulation cap 70. Because the insulation cap 70 is exposed to the high heat of the central plasma or reaction chamber 34 (FIG. 2), the insulation cap 70 is preferably made of a ceramic material that can withstand the high operating temperatures in this area. The insulation base 66 is also annular and surrounds the tubular support jacket 49 proximate the first end 49A of the tubular support jacket 49. The elongated insulation tube 68 extends around the tubular support jacket 49 between the insulation base 66 and the insulation cap 70. The insulation base 66 and the elongated insulation tube 68 can be fabricated as a single piece, wherein the two elements are molded from tempered glass, ceramic, and/or a high-temperature resistant polymer.

[0052] The elongated insulation tube 68 does not contact the inner tubular support jacket 49. Rather, a gap space separates the elongated insulation tube 68 from the tubular support jacket 49, therein forming a gas supply conduit 74. Likewise, the insulation cap 70 does not contact the tubular support jacket 49 so that a gap separates the insulation cap 70 from the tubular support jacket 49, therein continuing the gas supply conduit 74. A gas supply line 76 extends into the insulation base 66 of the insulator construct 64 and connects the working gas supply 22 (FIG. 1) to the gas supply conduit 74. As the working gas flows from the working gas supply 22 into the gas supply line 76, the working gas flows into the gas supply conduit 74 and runs along the length of the tubular support jacket 49 and thereafter flows past the electrode tip 46 into the reaction chamber 34.

[0053] As illustrated in FIG. 4, a protective collar 80 is mounted around the electrode tip 46. The protective collar 80 is dielectric and is capable of maintaining integrity in the high temperature environment of the central plasma zone or reaction chamber 34. The protective collar 80 has a first open end that connects to the insulation cap 70 and a second open end 82 at or near the small end of the electrode tip 46. The gas supply conduit 74 extends through the insulation cap 70 and discharges into the protective collar 80 between the protective collar 80 and the electrode tip 46. The working gas flows into the protective collar 80 and is confined around the electrode tip 46 and can only enter the central plasma zone or reaction chamber 34 by flowing past the electrode tip 46, where the electrode tip 46 forms an arc. In this manner, the working gas is turned into plasma by the arc as the working gas enters into the central plasma zone or reaction chamber 34.

[0054] A cylindrical casing 84 surrounds most of the elongated insulation tube 68, wherein the cylindrical casing 84 is interposed between the insulation base 66 and the insulation cap 70. The gas supply conduit 74 and the elongated insulation tube 68 separate the cylindrical casing 84 from the tubular support jacket 49. The cylindrical casing 84 is made of a highly thermally conductive material and is hollow. The interior of the cylindrical casing 84 is cooled with a flow of coolant that flows through the cylindrical casing 84 from an input port 86 to an output port 88. The cylindrical casing 84 therefore acts as an actively cooled heat sink, which absorbs heat directly from the insulation cap 70. The cylindrical casing 84 also absorbs heat passing through the elongated insulation tube 68. Lastly, the cylindrical casing 84 absorbs heat from the insulation base 66. It will therefore be understood that, during operation, the tubular support jacket 49 is internally cooled by the coolant flowing within the internal compartment 51 and externally cooled by the coolant flowing through the cylindrical casing 84. Additionally, the working gas flowing in the gas supply conduit 74 cools the tubular support jacket 49 which, in turn, cools the electrode tip 46. This active cooling reduces over-heating of the electrode tip 46 and prevents excessive consumption and erosion of the electrode tip 46. Furthermore, the high electrical conductivity of the tubular support jacket 49 reduces junction resistive heating, which allows high joule heating to occur at the electrode tip 46 for better thermionic emission of electrons that form and sustain an arc. Of course, the electrode assembly 42 illustrated and described with respect to FIG. 4 is one example of an electrode assembly that may be used to provide power, coolant and a working gas to an electrode used in the gasifier 10 of FIG. 1, and other electrode assembles could be used instead or in addition. For example, an electrode assembly illustrated in and described with respect to FIG. 4 of U.S. Pat. No. 10,208,263, which is hereby expressly incorporated by reference herein, could be used instead.

[0055] As previously stated, the working gas exiting the gas supply conduit 74 of FIG. 4 is ejected in a circle around the electrode tip 46. However, the generation of plasma or ionic gas is most effective when the working gas exiting around the electrode tip 46 does not disperse away from any arc that is emanating from the electrode tip 46. One way to help ensure that the working gas remains in a tight stream is to eject the working gas in a directed laminar flow, rather than a random turbulent flow. Referring to FIGS. 5 and 6, it will be understood that a laminar flow profile can be induced in the working gas by providing flow channels in the exterior of the tubular support jacket 49. FIG. 5 illustrates straight flow channels 94. FIG. 6 illustrates spiral or swirl flow channels 96. As the working gas flows over the flow channels 94, 96, the working gas is provided with a directed flow, be it straight or spiral. This directed flow tends to be laminar or swirl for typical flow rates being used. Moreover, the directed flow of the working gas through the flow channels 94, 96 has other unique performance characteristics. In particular, the tubular support jacket 49 may be made of a copper alloy that has a much better thermal conductivity than does the tungsten alloy of the electrode tip 46. In this case, the tubular support jacket 49 acts a heat sink to the electrode tip 46. As the working gas flows through the flow channels 94, 96, the working gas cools the tubular support jacket 49 which, in turn, cools the electrode tip 46. This configuration reduces over-heating of the electrode tip 46 and helps to prevent excessive consumption and erosion of the electrode tip 46. Furthermore, the high electrical conductivity of the tubular support jacket 49 reduces junction resistive heating within the electrode tip 46, which allows high joule heating to occur at the electrode tip 46 for better thermionic emission of electrons that form and sustain an arc.

[0056] FIGS. 7-9 illustrate a hybrid gasifier system 100 that includes both a set of plasma arc electrodes 102 and one or more plasma torches 104 disposed adjacent a reaction chamber 106 in a manner that creates and introduces plasma or ionic material into the reaction chamber 106 as well as producing electrical arcing within the reaction chamber 106 to provide for enhanced materials processing, such as waste-to-energy conversion, wastewater destruction, nano-material synthesis, and methane cracking to produce hydrogen, to name but a few. In particular, the hybrid gasifier system 100 of FIG. 7 includes the plasma torch 104 disposed in a vertical configuration with respect to the arc electrodes 102. As such, the plasma torch 104 is positioned vertically with respect to (e.g., above) the plasma or reaction chamber 106. Of course, more than one plasma torch 16 could be used depending upon the size of the plasma or reaction chamber 106, and the plasma torch 104 could be disposed at other locations with respect to the arc electrodes 102, such as below the electrodes 102 in the embodiment of FIG. 7 with the plume 108 pointing downward. In any case, the plasma torch 104 is disposed to inject plasma or ionic material into the chamber 106 in a direction that is orthogonal to, e.g., perpendicular to, the direction of the arcing and or working gas introduced into or created in the reaction chamber 106 by the arc electrodes 102. As will be understood, the plasma torch 104 of FIG. 7 creates a plasma jet 108 which emanates from the plasma torch 104 and fires downwardly in a vertical path through the center of the plasma or reaction chamber 106 and which may interact with or cross one or more arcs 110 within the reaction chamber 106 formed between the electrodes 102.

[0057] Of course, more than one set of arc electrodes 102 can be positioned within the system of FIG. 7. For example, between one and four sets of arc electrodes 102 can be used although more sets could be used as well. Additionally, these arc electrodes 102 can be any of the electrodes described herein with respect to FIGS. 1-6. In this example, the arc electrodes 102 are placed in lateral configurations to create free expanding arcs 110 in the plasma or reaction chamber 106. The free expanding arcs 110 interlink with the vertical plasma jet 108 from the plasma torch 104 and together the plasma (created by both the arc electrodes 102 and the plasma torch 104) and electrical arcs (created by the arc electrodes 102) provide for enhanced heating of and processing of the materials introduced into the reaction chamber 106 via an input (not shown in FIG. 7).

[0058] More specifically, each set of arc electrodes 102 includes an anode electrode and a cathode electrode. The free expanding arc 110 created across the plasma or reaction chamber 106 between the anode electrode and the cathode electrode of the various different sets of arc electrodes 102 interacts with the plasma jet 108 that is passing through the center of the plasma or reaction chamber 106 to provide a strong ionization source for creating ionized material (e.g., gas) in the reaction chamber 106. This ionization facilitates ignition and sustainment of the free expanding arcs 110 created by the various different sets of arc electrodes 102. The free expanding arcs 110, in turn, create an electrical field in the plasma or reaction chamber 106. Due to the presence of the electric field, part of the plasma jet 108 becomes an active arc and increases the temperature and reactivities of that portion of the plasma jet. The free expanding arcs 110 can therefore form without a supply of electrode working gas. However, a variety of working gas(es) can be supplied to and be emitted from the arc electrodes 102 to form the free expanding arcs 110 using electrode configurations as described in FIG. 4. The hybrid plasma jet and plasma arc system 100 produces a uniform and highly energetic large volume plasma field to enable a high temperature environment for waste-to-energy conversion, hazardous solid waste and wastewater destruction, nano-materials synthesis, methane cracking to produce hydrogen, and other plasma processing applications.

[0059] FIG. 8 depicts a perspective, partially cut-away view of a hybrid gasifier 120 implementing the vertical plasma torch configuration of FIG. 7. The hybrid gasifier 120 is essentially the gasifier 10 of FIG. 1 modified to include the vertically mounted plasma torch 104 of FIG. 7. The same or similar reference numbers are used in FIG. 8 as are used in FIGS. 1-7 to indicate the same or similar components. As illustrated in FIG. 8, the hybrid gasifier 120 includes multiple plasma units 16 stacked vertically on top of one another with electrode assembles 20 (FIG. 1) or 42 (FIGS. 2-6) mounted in the ports 40 (as shown in FIGS. 2-3) so that the anode and the cathode of a particular set of electrode assemblies 42 are disposed on opposite sides of the unit 16, i.e., 180 degrees around the unit 16 in which the electrodes are disposed, and so that the electrodes 42 extend radially into the reaction chamber 34. While the hybrid gasifier 120 of FIG. 8 is illustrated as including three plasma units 16 each with three sets of electrodes 42, more or less plasma units 16 could be used and more or less sets of electrodes 42 could be disposed in each plasma unit 16. Still further, while the sets of electrodes in adjacent plasma units 16 are illustrated as being mounted in a vertical line with respect to one another, the various electrodes 42 of different plasma units 16 could be offset from the electrodes in adjacent plasma units 16 by any desired angle (e.g., by 15 degrees, 20 degrees, 30 degrees, etc.).

[0060] Likewise, as illustrated in FIG. 8, a plasma torch 104 is mounted on the top of the hybrid gasifier 120 and has an output 122 that extends into or that is disposed at the top of the reaction chamber 34 above or higher than the uppermost plasma unit 16. Other configurations can be used in which more than one plasma torch 104 is included, for example including configurations in which 2, 3, 4, or more plasma torch 104 elements can be used. The plasma torch 104 is connected to a source of working gas and receives the working gas. As is typical, the plasma torch 104 (also referred to as a plasma jet generator or creator), creates or generates an arc between a cathode electrode and an anode electrode that are positioned close together inside the body of the torch 104 (not shown in FIG. 8). The working gas is then passed through the arc, therein creating a tongue of plasma which is then emitted from the output 122 of the plasma torch 104 as a stream of hot plasma 108 into a reaction chamber 34. Here, depending on the flow of the working gas into the plasma torch 104, the stream of hot plasma 108 may travel down through the center of the reaction chamber 34 (i.e., longitudinally with respect to a longitudinal axis of the plasma units 16) and intersect the reaction zones of one or more of the plasma units 16, thereby providing additional plasma or ionic material in the reaction chamber 34 to process material therein.

[0061] As illustrated in FIG. 8, the material to be processed may be introduced into the reaction chamber 34 via one or more openings or inputs 124 disposed in the top of the gasifier 120 around or near the plasma torch 104. However, the processing material input(s) 124 of the hybrid gasifier 120 may be located at one or more other locations on the gasifier 120, such as on the side of the gasifier 120 above the first (uppermost) plasma unit 16. The material to be processed, once introduced via an input 124, is gravity fed and flows down through the reaction chamber 34 through each of the stacked plasma units 16. Of course, this material contacts or interacts with the ionic gas produced by the plasma torch 104, especially near the inputs 124, and also interacts with the electrical arcs (shown in some cases in FIG. 8) that emanate from or that form between the electrode tips of the anode and cathode electrodes of the various pairs of electrode assemblies 42 extending into the reaction chamber 34. In the case in which the electrode assemblies 42 also provide a working gas within the chamber 34, which also becomes ionized (i.e., forms plasma), the material to be processed additionally interacts with this plasma, all of which helps heat and break down the material. Thus, as will be understood, the plasma from the plasma torch 104 provides additional heating and ionized gases which interact with and break down the material being processed. Likewise, the plasma stream 108 generated by the plasma torch 104 may be used to ignite one or more of the sets of electrodes 42 during start up by providing plasma and heat in the chamber 42. This operation may reduce or eliminate the need to cause the anode and cathode electrodes of a pair of electrode assemblies to be moved together or to touch to start the arcing activity. This operation may also reduce or eliminate the need to provide working gas into the reaction chamber 34 via the electrodes 42. In any event, after the material being processed travels generally vertically through (from top to bottom) the reaction chamber 34 and is subjected to the plasma generated by the plasma torch 104 and the plasma and arcs generated by the various pairs of electrode assemblies 42 in each of the plasma units 16, the processed material leaves the reaction chamber 34 via one or more outputs 15 at the bottom (lower vertical end) of the gasifier 120. The plasma torch 104 as illustrated in FIG. 8 can be disposed near the inputs 124, and can extend longitudinally into the reaction chamber 34 from the top, expelling or emitting plasma (e.g., a plasma plume or flame) directed downwards through the center of the reaction chamber 34. In cases where the feed or input material and/or the product or processed material includes solids, the plasma torch (or torches) 104 is suitably positioned longitudinally to direct the plasma plume 108 downward or otherwise co-currently with the flow of material through the reactor or gasifier 120 (e.g., as illustrated in FIG. 7), or laterally to direct the plasma plume 108 radially inward (e.g., as illustrated in FIG. 9 and discussed below).

[0062] As further examples of a hybrid gasifier, FIG. 9 depicts simple schematic views of a gasifier 130 having a lateral configuration in which one or more plasma torches 104, for example one plasma torch 104 as shown in panel (A) or two plasma torches 104 as shown in panel (B), are placed in lateral positions around the outer wall of the plasma unit 16 and are interspersed with arc electrodes 102 which are also mounted to the plasma unit 16 as previously described herein. The plasma torch 104 creates a plasma jet 108 that fires laterally (radially) into and towards the center of the plasma or reaction chamber 34, while the arc electrodes 102 produce free expanding arcs 110. As illustrated in panel (A) of FIG. 9, a single plasma torch 104 can provide a cross-interacting configuration of the free expanding arcs 110. As illustrated in panel (B) of FIG. 9, two colinear opposing plasma torches 104 can provide a parallel, non-interacting configuration of the free expanding arcs 110. The plasma jet (or jets) 108 may operate to ignite the free expanding arcs 110 and additionally travels into the center of the plasma unit 16 to provide a strong ionization source in the plasma chamber 34. This ionization facilitates ignition and sustainment of the free expanding arcs 110 which, in turn, create an electric field. Due to the presence of the electric field in the plasma chamber 34, a portion of the plasma jet 108 becomes an active arc and increases the temperature of that portion of the plasma jet. The free expanding arcs 110 can, in this case, form without a supply of electrode working gas. Alternatively, a variety of working gas(es) can be supplied to the arc electrodes 102 in the manners described herein to ignite the free expanding arcs 110 and provide additional ionization material within the chamber 34. It will be understood that the lateral configurations illustrated in FIG. 9 may be obtained, in one example, by mounting one or more plasma torches 104 into one or more of the unused ports 40 of FIG. 2. Moreover, while only one or two plasma torches 104 are illustrated in the embodiments of FIG. 9, multiple different plasma torches 104 (e.g., 2, 3, 4, 5, 6, or more plasma torches) may be mounted in a single plasma unit 16 and/or multiple different plasma torches 104 may be mounted in different ones of the stacked plasma units 16 of, for example, FIG. 1.

[0063] Both the vertical hybrid configuration of FIGS. 7 and 8, and the lateral hybrid configurations of FIG. 9 produce uniform and highly energetic large volume plasma fields to enable a high temperature environment for waste-to-energy conversion, hazardous solid waste and wastewater destruction, nano-materials synthesis, methane cracking to produce hydrogen, and other plasma processing applications. Moreover, both of these types of plasma torch placement configurations can be implemented in a hybrid gasifier having any of the electrode configurations, spacings and placements described herein, including any of the offset electrode configurations (e.g., FIGS. 10-14), non-offset electrode configurations, and gas vortex induction configurations (e.g., FIGS. 17-19) described in more detail herein.

[0064] It will be noted that in each of the embodiments described above, each set of arc electrodes 20, 42, 102, 104 is disposed around the plasma unit 16 and is directed inwardly in a radial direction, with the anode electrode and the cathode electrode of each set or pair of electrodes being disposed on the opposite side of the plasma unit 16, such that these two electrodes are offset 180 degrees apart from one another circumferentially around the plasma unit 16. As a result, the arc traveling between these electrodes passes through the center of the reaction chamber 34. Of course, when two or more sets of electrodes are so disposed around a plasma unit 16, the arcs from each of these sets of electrodes pass through the center (or very close to the center) of the reaction chamber 34. These multiple arcs at or near the center of the reaction chamber 34 produce a very hot area near the center of the chamber 34 which provides for significant processing of material at the center of the chamber. This feature can be beneficial in some instances. However, this configuration can result in less plasma and arc processing and/or heat in other areas of the reaction chamber 34 not at the center. It may be beneficial to cause the arcs from different ones of the sets of electrodes to follow one or more paths that do not go through the center of the chamber, thereby dispersing the arcs and plasma generation more evenly throughout the reaction chamber 34. This feature then leads to more even processing of material within the chamber 34, no matter whether the material travels through the chamber 34 at the center or off center of the chamber 34.

[0065] Thus, in one embodiment, an improved plasma or ionic reactor described herein uses multiple sets of opposed arc electrodes disposed around a reaction chamber in a manner that operates to disperse the arcs from multiple sets of electrodes over a larger area of the reaction or plasma chamber 34, thereby effectively increasing the size of the reaction zone in which at least one arc is present. This feature then produces more areas within a plasma or reaction chamber at which at least one arc is present, which increases the temperature profile across the entire horizontal or lateral cross section of the reaction. In particular, to change the arcing profile within the reaction chamber to be more even across the reaction chamber, the anodes and cathodes of various pairs of electrodes are disposed at circumferential angles other than 180 degrees with respect to one another around the outer wall of the reaction chamber, so that the anode and cathode of a particular pair of electrodes are disposed at an acute angle (less than 90 degrees) or an obtuse (between 90 and 180 degrees) angle or at 90 degrees with respect to one other. Moreover, the anodes and cathodes of different sets of electrodes are juxtaposed with each other around the chamber to intersperse the polarity of adjacent electrodes. As a result, some or all of the arcs produced by the electrodes do not necessarily travel directly through the center of the reaction chamber but traverse the chamber offset from the center of the chamber. In this manner, arcs produced by different sets of electrodes travel through the reaction chamber on various different paths through the chamber, thereby better distributing the arcs throughout the reaction chamber. The dispersal of arcs more evenly throughout the reaction chamber provides for better or more even processing of the material flowing through the chamber and enables the chamber to be used for new purposes, such as producing carbon nanoparticles.

[0066] As an example, FIG. 10 illustrates a first offset electrode configuration that may be used to provide for better arc coverage in a reaction chamber. In particular, FIG. 10 illustrates an axial or top inner view of a gasifier 210 having a plasma unit 212, which may be, for example, one of the plasma units 16 of FIG. 1. In this case, the plasma unit 212 includes four pairs of arc electrodes 216 disposed therein and the wall of the plasma unit 212 defines a plasma chamber 217. Moreover, the sets or pairs of arc electrodes 216 are set into the wall of the plasma unit 212 and are installed such that each set of arc electrodes 216 includes a cathode electrode 218 and an anode electrode 220.

[0067] To achieve and maintain better plasma arc symmetry and stability, the sets of arc electrodes 216 are arranged in an alternating polarity configuration so that each cathode electrode is circumferentially disposed between two anode electrodes and each anode electrode is circumferentially disposed between two cathode electrodes. As such, the electrodes 216 alternate in polarity as they go around the circumference of the plasma unit 112. In the illustrated embodiment, the plasma module 212 has four sets of arc electrodes 216, which provides eight total electrodes with four cathode electrodes 218A, 218B, 218C, 218D and four anode electrodes 220A, 220B, 220C, 220D. The electrodes 216 are disposed evenly around the wall of the unit 212 and so are separated from their nearest neighbor by an angle of 45 degrees. Moreover, the two electrodes (anode and cathode) within a set of arc electrodes 216 are arranged at a particular obtuse angle in relation to one another, with this angle being 135 degrees in the system of FIG. 10. Thus, the placement of the arc electrodes 216 embody a specific directional rotation to achieve a complete alternating electrode polarity for the eight electrodes. This arrangement of alternating electrode polarity produces a plasma arc system or unit 210 with very stable arc formations and a more uniform high temperature plasma field.

[0068] As illustrated in FIG. 10, the four sets of arc electrodes 216 create four arcs 222 in the plasma chamber 217. An A set of arc electrodes 216 has a first anode electrode 220A located at the 0 degree or top position (in FIG. 10) and the associated first cathode electrode 218A is offset clockwise by an obtuse angle of 135 degrees from the first anode electrode 220A. As will be understood, the electrodes 218A and 220A are powered by the same power supply.

[0069] Moreover, a B set of arc electrodes 216 includes the cathode electrode 218B and an anode electrode 220B. The cathode electrode 218B is disposed adjacent to and is offset by 45 degrees (in the clockwise direction) from the first anode electrode 220A. However, the second anode electrode 220B is offset by 135 degrees in the counterclockwise direction from the second cathode electrode 218B. Additionally, the electrodes 218B and 220B are powered by the same power supply which may be a different power supply than the power supply providing power to the A set of electrodes 218A, 220A.

[0070] Still further, a C set of arc electrodes 216 includes the cathode electrode 218C and an anode electrode 220C. The third anode electrode 220C is adjacent to and between the second cathode electrode 218B and the first cathode electrode 218A, is offset clockwise by 90 degrees from the first anode electrode 220A and is offset by 135 degrees in the clockwise direction from the third cathode electrode 218C. Additionally, the electrodes 218C and 220C are powered by the same power supply, which may be a different power supply than the power supply providing power to the A set of electrodes 218A, 220A and/or to the B set of electrodes 218B, 220B.

[0071] Finally, a D set of arc electrodes 216, includes a cathode electrode 218D and an anode electrode 220D. The fourth cathode electrode 218D is disposed adjacent to and between the first anode electrode 220A and the second anode electrode 220B. Likewise, the fourth cathode electrode 218D is offset by 180 degrees from the first cathode electrode 218A and is offset by 135 degrees in the counterclockwise direction from the fourth anode electrode 220D. Additionally, the electrodes 218D and 220D are powered by the same power supply, which may be a different power supply than the power supply providing power to the A set of electrodes 218A, 220A, and/or to the B set of electrodes 218B, 220B, and/or to the C set of electrodes 218C, 220C.

[0072] In this configuration, the anode electrodes 220A and 220D are disposed directly opposite from each other in a first orthogonal axis and the anode electrodes 220B and 220C are disposed directly opposite from each other in a second orthogonal axis. Similarly, the cathode electrodes 218A and 218D are disposed directly opposite from each other in a third orthogonal axis and the cathode electrodes 218B and 218C are disposed directly opposite from each other in the remaining orthogonal axis. This arrangement achieves an alternating electrode polarity for all adjacent electrodes and provides a very stable arc configuration with a very large and uniform high temperature plasma field for materials processing within the chamber 217. In particular, the arcs 222 produced by the different sets of electrodes 216 cross each other and join near, but not directly at, the center of the plasma chamber 217 resulting in a larger arc field in the chamber 217 in which the arcs 222 do not all pass through the same point in the chamber 217 (i.e., the center point). Moreover, the arcs 222 behave like a single arc in the middle of the plasma chamber 217, so that the joint heating power in the center of the chamber 217 is substantially higher than sum of all the heating power of each individual arcs 222.

[0073] Referring to FIG. 11, an alternate plasma arc system or unit 230 is illustrated. In this plasma arc system 230, there are four sets of arc electrodes 332 marked as an A set, a B set, a C set and a D set. Here, each set of electrodes is powered separately by, for example, a different power supply. Each of the sets of electrodes 332 has an anode electrode 334 (334A, 334B, etc.) and a cathode electrode 336 (336A, 336B, etc.) and, for each set of arc electrodes 332, the anode electrode 334(A-D) is positioned adjacent to the associated cathode electrode 336(A-D) with a 45-degree angle of separation (circumferentially). This electrode configuration achieves alternating electrode polarity with the anode electrode 334 and cathode electrode 336 of an associated set of electrodes 332 being disposed in a manner that is not directly opposite (i.e., 180 degrees) around the unit 330. In this configuration, each anode electrode 334 is disposed directly opposite from another anode electrode 334 in one or more orthogonal axes while each cathode electrode 336 is disposed directly opposite from another cathode electrode 336 one or more other bisecting orthogonal axes. This arrangement achieves an alternating electrode polarity for all adjacent electrodes and, as a result, as illustrated in FIG. 11, the sets of arc electrodes 332 produce arcs 338 that do not necessarily cross each other. However, in some cases, each arc 338 may have a small portion of the arc body that overlaps near the center of the plasma chamber 317. This partial overlap of arcs 338 behaves like a small additional arc in the middle of the plasma arc system 330. The heating power of the combined partial arc currents in the center supplements the heating power of each individual arc 338 in the plasma arc system 330 and forms a uniform high temperature plasma for materials processing.

[0074] FIGS. 12-14 illustrate three alternative plasma arc systems or units 340, 350, 360. In each embodiment, anode electrodes and cathode electrodes are arranged to achieve alternating electrode polarity that provides the systems 340, 350, 360 with very stable arc formations and uniform high temperature plasma fields.

[0075] Referring to FIG. 12, there are three sets of arc electrodes 342 (labeled as A, B and C sets of electrodes) with the anode electrodes 344 and the cathode electrodes 346 of each set being arranged 180 degrees apart. Every anode electrode 344 is disposed adjacent to and between a cathode electrode 346 to the left and to the right. Arcs 348 are produced by the sets of arc electrodes 342 and arcs 348 join or cross at the center of the plasma chamber 317. Moreover, a portion of the joined arcs 348 behaves like a single arc. The heating power of this joined arc region is much higher than the peripheral arc regions.

[0076] FIG. 13 illustrates another asymmetric arrangement of sets of arc electrodes in a plasma unit 350 that includes three sets of electrodes, 351A, 351B, 351C disposed around the unit 350. Each of the sets of electrodes 351A, 351B, and 351C may be powered by a separate power supply. The first set of arc electrodes 351A includes an anode electrode 352 and a cathode electrode 353 arranged 180 degrees apart on (i.e., on opposite sides of) the unit 350. This first set of arc electrodes 351A produces a straight arc 354 that travels through the center of the chamber 317. The second set of arc electrodes 351B has an anode electrode 356 and a cathode electrode 357 that are offset by 60 degrees, while the third set of arc electrodes 351C has an anode electrode 358 and a cathode electrode 359 that are offset by 60 degrees. Moreover, the anode electrodes 352, 356 and 358 are each disposed adjacent to, and are disposed 60 degrees apart from two of the cathode electrodes 353, 357 and 359, so that the unit 350 has interspersed or alternating anode and cathode electrodes when going around the unit 350. Moreover, the 60 degree offset positions of the anodes and the cathodes of the sets of arc electrodes 351B and 351C place these sets of electrodes across the unit 350 from each other and produces secondary arcs 358 that are divided by the straight arc 354. The result is partial arc mixing at the center of the plasma module, which produces a central heating power higher than the peripheral arc regions while still providing arc creation over a wider cross section of the unit 350.

[0077] FIG. 14 illustrates a plasma unit 360 having three sets of arc electrodes 362A, 362B and 362C, each having an anode electrode 364 and a cathode electrode 366 that are arranged 60 degrees apart. This configuration is very similar to the four set of electrode configuration illustrated in FIG. 11. In this configuration, there will be partial mixing and joining of arcs 368 at the center of the plasma chamber 317. The partial mixing and joining of the arcs 368 produce a joint heating power that is higher than the peripheral arc regions. In these configurations, all plasma electrodes 364, 366 can be positioned to achieve alternating electrode polarity thus increasing arc stability.

[0078] Of course, while various different arc electrode placements are illustrated and described with respect to FIGS. 10-14, it will be noted that, for each of these configurations, the arcs produced in the plasma chamber reinforce one another and these arrangements all include alternating electrode polarity for all adjacent electrodes. This aspect of the illustrated configurations provides for a very stable arc configuration and a very large and uniform high temperature plasma field for materials processing. Moreover, in some cases, some or all of the arcs may cross each other and in other cases none of the arcs cross each other. Still further, with these various configurations, no arcs, one arc, a plurality of the arcs less than all of the arcs or all of the arcs may cross through the center of the reaction chamber. Still further, the arcs may cross each other or not cross each other but may join near the center of the plasma chamber and behave like a single arc in the middle of the plasma unit. As such, the joint heating power in the center of the reaction chamber may be substantially higher than the sum of all the heating power of each of the individual arcs while still providing for the arcs to be spread out throughout the cross section of the chamber in a more even or distributed manner. The temperature at or near the center region of the reaction chamber is expected to be near or at least 3000K and even up to or exceeding 5000K, and this temperature can cause the complete disintegration of feed materials.

[0079] Of course, other arc electrode placement configurations can be used instead of those specifically described and shown herein. For example, while the embodiments of FIGS. 10-14 illustrate configurations with three and four sets of electrodes, other embodiments could include two sets of electrodes or more than four sets of electrodes. Still further, while it is desirable to interspace the sets of electrodes such that anode electrodes and the cathode electrodes are interspersed with or adjacent one another around the entire plasma unit, this feature may not be critical and so, in some cases, two anode electrodes and/or two cathode electrodes may be placed adjacent to one another while interspersing other ones of the anode and cathode electrodes. Likewise, all of the electrodes illustrated in FIGS. 10-14 are equally separated around the plasma, by an angle that is calculated as 360 divided by the total number of electrodes. However, in some cases, the electrodes do not need to be evenly spaced around the perimeter of the plasma unit and so some adjacent electrodes could be separated by a first angle and other adjacent electrodes could be separated by other angles greater than or less than the first angle. Moreover, the anode and cathode electrodes of a particular pair of electrodes can be separated by any desired angle around the perimeter of the unit, such as at an acute angle, at 90 degrees, at an obtuse angle or at 180 degrees. While the embodiments of FIGS. 10-14 illustrate various different anodes and cathodes of an electrode pair being separated by 45, 60, 90, 135 and 180 degrees, other angles could be used instead (and these angles may be dependent on or effected by total number of electrodes). Still further, different pairs of electrodes in the same unit may have their respective anode and cathode electrodes separated by different angles. Thus, as illustrated in FIG. 13, one pair of electrodes has the respective anode and cathode electrodes separated by 180 degrees while other pairs of the electrodes have their respective anode and cathode electrodes separated by 60 degrees. Of course, other combinations of electrode separations could be used instead or in addition to those described and illustrated herein. Likewise, various different combinations of electrode spacings or offsets can be used so that, in some cases, none of the arcs produced by the various sets of electrodes cross each other, in other cases each arc produced by each set of electrodes crosses every other arc produced by the other sets of electrodes, and in other cases an arc produced by one or more of set of electrodes may cross one or more of the arcs produced by the other sets of electrodes but not all of the arcs produced by the other sets of electrodes. Still further, in many cases, the arcs produced by a set of electrodes will not be aligned with (e.g. pass through) the center of the reaction chamber due to the anode electrode and the cathode electrode of the set of electrodes being spaced apart at an angle other than 180 degrees.

[0080] In any event, the arcing environment achieved by the embodiments described in FIGS. 10-14 is particularly useful for producing carbon nanoparticles, such as carbon nano-onions and for methane cracking. More particularly, carbon nano-onions (CNOs) are known as multi-shell fullerenes and were discovered in 1992. Carbon nano-onions are structured concentric shells of carbon atoms. Over the years, different methods for the synthesis of carbon nano-onions have been developed and studied. In addition, the chemical functionalization of carbon nano-onions has been investigated and several synthetic pathways were found to be applicable for the introduction of a variety of functional groups. Chemically modified carbon nano-onions were probed in different fields of application and have been revealed to be a promising nanomaterial that attracts a growing interest among researchers and opens new avenues for investigation. Currently, carbon nano-onions can only be produced in gram-scale quantities by mechanical stressing of commercially available nano-diamonds. Alternatively, this production is performed by the combustion of naphthalene, and by arc flashes between graphite electrodes under water. However, current methods of manufacturing carbon nano-onions are unable to produce industrial levels of product in a short period of time. The availability of large quantities of CNOs would open up applications for these exotic nano materials.

[0081] Advantageously, the plasma arc systems described herein can produce CNOs in large quantities. One, single, small plasma system as described herein is capable of producing kilograms of the carbon nano-onions in a matter of a few hours. Multiple parallel systems can increase production quantities and provide rapid delivery at industrial levels, on site and on demand. The reason for this ability is that the expanding arc produces a very high temperature, uniform, and large plasma field to synthesize the CNOs. Generally, the arc electrodes that produce these arcs must be arranged in alternating polarity to sustain a stable, uniform, and conjoined arc field. It is this high temperature conjoined active arc field that makes the high-rate synthesis of carbon nano-onions possible. Advantageously, the arc electrode plasma systems described herein can use any gas, preferably, argon, hydrogen and/or nitrogen, to form the plasma. In one iteration, graphite electrodes may be used to produce high purity CNOs. Feedstock for the process can use high purity carbon black derived from cracking of high purity hydrocarbon gases or liquids, high purity graphite powder or other carbon-rich materials.

[0082] In addition to producing carbon nano materials, the high temperature of the plasma arc systems described herein can also be used to crack hydrocarbons, such as methane (CH.sub.4). Methane is a more potent greenhouse gas than carbon dioxide and is a material global warming concern. Global warming can lead to polar ice cap melting, sea level rise, and loss of land mass. Methane sequestration is an international effort to reduce global warming. Cracking hydrocarbons to produce hydrogen and carbon, and then sequestering the carbon, reduces greenhouse gases and promotes the development of a hydrogen economy.

[0083] In particular, methane can be cracked and reduced to hydrogen and solid carbon. However, current technologies lack the ability to efficiently generate a sufficiently high temperature environment to completely crack methane. The result is partial cracking with higher molecular weight hydrocarbons as impurities. Among all of the hydrocarbon gases, methane is the most stable. As a result, the complete cracking of methane to hydrogen and solid carbon is extremely difficult due to the very high temperatures required. The plasma arc systems described herein have the ability to efficiently generate a temperature field capable of fully cracking methane.

[0084] In particular, referring to FIG. 15, test results are shown. Using the plasma arc system previously described to crack methane, only 0.041% CH.sub.4 residue was detected. Thus, 99.96% of the feed methane was cracked to hydrogen and solid carbon. The table of FIG. 15 illustrates a product gas analysis. The total concentration of impurity hydrocarbon gases was 6.17% in the product gas and the hydrogen concentration was 93.83%. In another gas sample, the results of which are illustrated in FIG. 16, only 0.008% CH.sub.4 residue was detected, and this shows that 99.99% of the feed methane was cracked to hydrogen and solid carbon. The amount of impurity hydrocarbon gases significantly decreased, and their total concentration was 3.51%, while the hydrogen concentration was 96.49% in the product.

[0085] With the demonstration of almost 100% cracking of CH.sub.4 to H.sub.2 and solid carbon, it is conceivable that the cracking of other hydrocarbon gases in the plasma arc system could approach 100%. It is also understood that the carbon black produced from methane or other hydrocarbon cracking in these arc configurations will contain CNOs and other nano-carbon allotropes.

[0086] As noted above, many of the plasma reactors or systems described herein (e.g., with respect to FIGS. 1-9 at least), have sets of opposed arc electrodes. During operation, an unconfined arc is created between a cathode electrode and an anode electrode, and a working gas is then passed through the arc, therein creating plasma. The working gas is injected into a plasma chamber around the cathode electrode and the anode electrode which enables the passing working gas to help cool the cathode electrode and the anode electrode. Moreover, as described with respect to FIGS. 5 and 6, it is beneficial to keep the working gas in a confined stream that follows the path of the arc between the cathode electrode and the anode electrode. In this manner, the working gas is exposed to the heat of the arc for a longer period of time. To help keep the working gas in a confined stream, a rotational vortex may be created in the working gas as it flows into the plasma chamber wherein the mid-axis of the vortex is oriented to follow the path of the arc (as illustrated in FIG. 6).

[0087] When the cathode electrode and the anode electrode are positioned on directly opposite sides of a plasma chamber, as has been the case in the past, creation of the same rotational vortex in the working gas as this gas exits both the cathode electrode and the anode electrode causes the two vortexes to spin in opposite directions when they intersect in the center of the plasma chamber. The opposite spin causes the vortexes to cancel or destructively interact, which causes the working gas to disperse. This operation may create significant instabilities for the arc column.

[0088] FIGS. 17-19 depict or illustrate a plasma unit, which may be, for example, any of the plasma units 16, 100, 120, 130, 340 and 350 of FIGS. 1-3, 7-9, 12 and 13, which can be used to better direct flow of working gas in the reaction chamber. Referring to FIG. 17, a plasma arc system 410 may be used to enhance materials processing such as waste to energy conversion, wastewater destruction, nano materials synthesis, and methane cracking to produce hydrogen and nano-carbons. In FIG. 17, it can be seen that there is an anode electrode assembly 412 and a cathode electrode assembly 414 set in a plasma module on opposite sides of a plasma chamber 416. The anode electrode assembly 412 and the cathode electrode assembly 414 generate an arc 418 that extends across the plasma chamber 416 in any of the manners previously described herein.

[0089] A working gas 420 is passed through the anode electrode assembly 412 and the cathode electrode assembly 414 and operates to cool these assemblies 412, 414. Moreover, the working gas 420 is converted into plasma by the arc 418. As will be explained, the working gas 420 is directed into a reinforced vortex 422 as it passes through the electrode assemblies 412, 414. The reinforced vortex 422 spins the working gas 420 and allows the working gas 420 to propagate along the arc 418 without dispersing or dispersing to a lesser amount than in previous systems which introduced working gas into a reaction chamber via one or more electrodes.

[0090] As better illustrated in FIG. 18, however, the first vortex 424 exiting the anode electrode assembly 412 spins in a first direction (when looking out from the tip of the first electrode 412), which can be either clockwise or counterclockwise, while the second vortex 426 exiting the cathode electrode assembly 414 is configured to spin in the opposite direction (when looking out from the tip of the electrode 414). Because the anode electrode assembly 412 and the cathode electrode assembly 414 are oriented 180 degrees apart on opposite sides of the plasma chamber 416, they form mirror images opposite to each other, and the first and second two vortexes 424, 426 will now physically align. Furthermore, the first vortex 424 and the second vortex 426 spin in the same direction due to the different spins induced into these vortexes at the electrodes 412 and 414. The result is that the first vortex 424 and the second vortex 426 reinforce each other to create the single reinforced vortex 422 that spans fully across the plasma chamber 416. The reinforced vortex 422 travels the same pathway as the arc 418 so that the working gas 420 is kept close to the arc 418 without dispersing. This configuration improves the arc column stability and creates more plasma per unit of working gas 420.

[0091] As illustrated in FIG. 18, in both the anode electrode assembly 412 and the cathode electrode assembly 414, the working gas 420 passes through grooves 428 that are formed on an electrode body or core 430 and between a surrounding housing 432. In the anode electrode assembly 412, the grooves 428 are formed into either a clockwise or counterclockwise spiral. As such, when the working gas 420 passes through the anode electrode assembly 412, the working gas 420 will spin in the grooves 428. When the working gas 420 exits the grooves 428, the spinning movement remains and the working gas 420 progresses in a vortex (the vortex 424).

[0092] However, the cathode electrode assembly 414 has grooves 428 (also disposed in an electrode body or core 430 and between a surrounding housing 432), but the grooves 428 of the cathode electrode assembly 414 rotate in the opposite direction to those used in the anode electrode assembly 412 (when viewed from the same direction, e.g., looking out from the base to the tip of the electrodes 413, 414)). Accordingly, the working gas 420 exits the cathode electrode assembly 414 with a vortex of opposite spin (the vortex 426) with respect to the electrode 414. However, because the first vortex 424 exiting the anode electrode assembly 412 is 180 degrees opposite the second vortex 426 exiting the cathode electrode assembly 414, they are mirror images opposite to each other, and these two vortexes 424, 426 spin in the same direction or circular motion within the plasma chamber 416. As a result, the two vortexes 424 and 426 constructively add to one another to create the vortex 422 which spans the entire distance between the anode electrode assembly 412 and the cathode electrode assembly 414. This stable vortex provides for better gas column formation and helps prevent the working gas 420 from dispersing in or near the center of the chamber 416, which leads to better arc formation and creation of plasma within the chamber 416.

[0093] Referring to FIG. 19, an alternate embodiment has an anode electrode assembly 432 and a cathode electrode assembly 434, each of which has electrode core 436 and a surrounding housing 438. Grooves 440 are formed on the interior surface of the housings 438 (which is part of a working gas passage) so that the working gas 420 passes through grooves 440. In the anode electrode assembly 432, the grooves 440 are formed into either a clockwise or counterclockwise spiral when looking out of the housing 438 in the longitudinal direction. As such, when the working gas 420 passes along the anode electrode assembly 432, the working gas 420 will spin in the grooves 440 in the determined circular direction. When the working gas 420 exits the grooves 440 the spinning movement remains and the working gas 420 progresses in a first vortex 442.

[0094] However, the cathode electrode assembly 434 has grooves 440 that rotate in the opposite direction to those used in the anode electrode assembly 432 when looking out of the housing 438 of the cathode electrode assembly 434 in the longitudinal direction. Accordingly, the working gas 420 exits the cathode electrode assembly 434 with a second vortex 444 of opposite spin. However, because the first vortex 442 exiting the anode electrode assembly 432 is 180 degrees opposite the second vortex 444 exiting the cathode electrode assembly 434, they are mirror images opposite to each other, and these two vortexes 442, 444 spin in the same direction within the plasma chamber 446. Again, the two vortexes 442 and 444 constructively add to one another to create a vortex that spans the entire distance between the anode electrode assembly 432 and the cathode electrode assembly 434. This stable vortex provides for better gas column formation and helps prevent the working gas 420 from dispersing in or near the center of the chamber 446, which leads to better arc formation and creation of plasma within the chamber 446.

[0095] Of course, the plasma arc modules having electrode assemblies which produce a better gas vortex have been described herein in only two exemplary embodiments, for the purposes of illustration and discussion. However, these modules could be produced in other manners as well and so the illustrated embodiments are merely exemplary and should not be considered a limitation when interpreting the scope of the claims. For example, the grooves described above could be disposed on other surfaces of the electrodes or electrode assemblies that are exposed to the flow of working gas into the reaction chamber. Additionally, the grooves described herein could be disposed on multiple surfaces, such as on both the electrode body or core as illustrated in FIG. 18 and on the interior surface of the electrode housing as illustrated in FIG. 19. Alternatively, one of the pair or set of electrodes (e.g., the cathode electrode) may have the grooves formed on one of the electrode body or the interior surface of the electrode housing while the other one of the pair or set of electrodes (e.g., the anode electrode) may have the grooves formed on the other one of the electrode body or the interior surface of the electrode housing. Moreover, it will be understood that the use of arc electrodes disposed on opposite sides of a reaction chamber that introduce a working gas into the chamber using differently directed vortexes to cause the vortexes to constructively add in the chamber, as described herein, can be used in plasma or reaction chambers with any number of such oppositely opposed sets of electrodes (including one set or multiple sets), including for example, in any of the plasma units described herein, but especially in the plasma units depicted in FIGS. 1-3, 7-9, 12 and 13. In this case, the oppositely opposed electrodes will have grooves therein that cause the working gas to spiral in different circular directions as they leave the electrode assemblies, but the opposed electrodes may be electrodes from the same or from different sets or pairs of electrodes. Thus, the opposed electrodes (those disposed directly opposite one another across the reaction chamber or reaction zone) may be an anode and a cathode electrode of the same set of electrodes, may be an anode and a cathode electrode of different sets of electrodes, may be two anode electrodes of different sets of electrodes or may be two cathode electrodes of different sets of electrodes. Still further, these electrodes with working gas vortex creation can be used in other than circular or cylindrical reaction chambers, including in rectangular, square, octagonal, etc. chambers or in tube shaped chambers in which the electrodes are disposed at the longitudinal ends of the tube. Likewise, the grooves in the various electrode assemblies may have grooves of any desired pitch (that is, the inter-groove spacing between the adjacent grooves of the spiral) to create tighter or looser vortexes. Additionally, the groove pitches of the different electrode assemblies or electrodes of a particular pair of electrodes (i.e., for the anode electrode and the cathode electrode) may be the same or may be different.

[0096] Advantageously, the gasifiers described herein provide for or implement an ultra-high temperature ionic gasification process that can be used in an environmentally friendly manner to dispose of dried or partially dried biosolids from, for example, wastewater treatment plants as well other wastes, such as municipal solid waste (MSW), to produce, for example, renewable syngas that can be used to provide heat, power, renewable fuels, renewable hydrogen, and/or as renewable raw material for chemical production. The systems described herein do so by generating electrical arcs across the interior (e.g., diameter) of the gasifier reaction chamber creating a localized, controlled temperature in excess of 3000 C and in some cases in excess of 5000 C, along with ionic gas or particles (plasma). This ultra-high temperature gasification zone and active ionic environment combine to, very effectively and efficiently, break down molecules into their constituent atoms and ions, in a process called complete molecular dissociation and ionization. This ultra-high temperature ionic zone will also rapidly decompose impurities in the feed stock such as microplastics and PFAS (Per- and Polyfluorinated Substances). Moreover, as the gasified stream exits the gasification zone, a rapid, controlled temperature drop recombines these atoms, forming a very pure syngas with no or very little system scaling, making it suitable for treating wastewater residuals, focusing on drying and gasifying solid residuals for energy production, contaminant destruction and volatile carbon reduction. This rapid temperature drop also tends to maximize production of desirable molecules like hydrogen and carbon monoxide while minimizing the production of less desirable molecules such as water, ammonia, and carbon dioxide. Materials to be processed are preferably dried or partially dried biosolids.

[0097] Still further, it will be understood that the gasifiers described herein can be used in a gasifier mode in which oxygen is present in the reaction chamber thereof, or in a pyrolysis mode or a partial oxidation mode in which no or limited oxygen is present in or introduced into the reaction chamber. In some embodiments, the gasifier can be operated in a pyrolysis mode with no added oxygen (e.g., no added oxygen-containing reactive gases), but there can be some oxygen present in the input material, for example when the biosolids material contains some elemental oxygen and/or some (liquid) water.

[0098] Thus, the reactors disclosed herein, for example the plasma or ionic reactors or gasifiers, can be used in a method for processing or remediating a (waste) material. The method includes receiving an input material to be processed within a reaction chamber (e.g., of a plasma or ionic reactor), where the input material includes a biosolids material. The method further includes energizing one or more sets of electrodes (e.g., of the plasma or ionic reactor), where each set of electrodes includes an anode electrode and a cathode electrode, with each anode electrode and cathode electrode having an electrode tip exposed to the reaction chamber. The method further includes creating an electrical arc between the anode electrode tip and the cathode electrode tip within the reaction chamber to subject at least some of the input material to electrical arcing, thereby reacting at least a portion of the biosolids material and forming a processed material including hydrogen (H.sub.2) and carbon monoxide (CO).

[0099] An input material can include a biosolids waste material, which can include some (liquid) water therein such that the input material can be in the form of a wet biosolids cake. An input material, for example a wet solids input material (e.g., biosolids or otherwise), suitably has a water content of 20 wt. % or less, or 15 wt. % or less, for example at least 0.001, 0.01, 0.1, 1, 2, 5, or 7 wt. % and/or up to 2, 4, 6, 8, 10, 12, 13, 15, or 20 wt. %, expressed either on a wet weight basis (or total basis) or a dry weight basis. Processing biosolids materials with water content higher than about 20 wt. % is possible, and it can create products with higher hydrogen (H.sub.2) and carbon monoxide (CO) components, but it may require a higher amount of energy to evaporate and dissociate water (e.g., as compared to a pre-reactor drying step).

[0100] In some embodiments, a wet biosolids input material can have a higher water content, for example being in the form of a slurry or dispersion. In such cases, the high-water content material can initially contain at least 20, 30, 40, or 50 wt. % and/or up to 50 or 60 wt. % water (total basis). Processing higher water content biosolids may be advantageous to adjust the hydrogen to carbon monoxide ratio of the processed gas and/or reduce/eliminate a steam feed to the reactor. In-situ vaporization of high-water content biosolids can be used to initiate a radical reaction to yield higher hydrogen concentration in the processed gas.

[0101] The biosolids material can be a product of the treatment of municipal wastewater that has been stabilized, partially stabilized, or not stabilized by aerobic and/or anaerobic digestion or other biological or chemical processes to stop biodegradation and reduce pathogens and odor. During the digestion process, bacteria and other microbes break down the waste material and, in the process, consume some of the energy content of the original biosolids for their own metabolism and/or convert some of the waste to methane. While digestion has the advantages of reduced pathogens and odor, digestion also leads to energy leaving the feed material, leaving less energy and less available/convertible carbon in the biosolids for the reactor to convert to syngas product. In embodiments, the biosolids feed to the reactor can include only digested biosolids, only undigested biosolids, or a blend of digested and undigested biosolids (e.g., at least 5, 10, 20, 30, 40, 50, 60, 70, 80, or 90 wt. % and/or up to 10, 20, 30, 40, 50, 60, 70, 80, 90, or 95 wt. % digested or undigested biosolids relative to total biosolids). In embodiments, the biosolids feed can include undigested biosolids received directly (e.g., onsite or as a feed from) wastewater treatment facility, thus converting the biosolids to a higher-energy product while also reducing or eliminating the potential for pathogen and/or odor build-up.

[0102] Biosolids materials can be further dewatered and/or dried. Biosolids materials, such as pellets, particles, or other shapes, can be dewatered in drying beds, filtering, centrifuging, or any other methods known in the art. Biosolids materials can be further dried using thermal methods like using rotary dryers or any other methods known in the art to form dried biosolids particles. Commonly, the pellets can be produced in rotary dryers where the rotation of the drum tends to produce round pellets, and such pellets can be used as formed or ground/milled/sieved to a suitable size. In embodiments, a dryer can be used to form biosolids particles having a more irregular or granular shape, for example having a desired size distribution without the need for further size modification or classification. In embodiments, a dried or dewatered biosolids material suitably has a water content of 15 wt. % or less, or 10 wt. % or less, for example at least 0.001, 0.01, 0.1, 1, 2, 5, or 7 wt. % and/or up to 2, 4, 6, 8, 10, 12, 13, or 15 wt. %, expressed either on a wet weight basis (or total basis) or a dry weight basis.

[0103] Dried biosolids particles can have a particle size, for example an average particle size, up to about 4 mm, up to about 2 mm, in a range of about 0.3 mm to about 4 mm, or in a range of about 0.5 mm to about 2 mm. For example, the average particle size of biosolids particles can be about 0.3 mm, or about 0.5 mm, or about 0.7 mm, or about 1.0 mm, or about 1.5 mm, or about 2 mm, or about 3 mm, or about 4 mm, or any values therebetween or ranges defined by such values, such as at least 0.001, 0.01, 0.02, 0.1, 0.2, 0.3, 0.5, 0.7, or 1 mm and/or up to 0.1, 0.2, 0.3, 0.5, 0.6, 0.8, 1, 1.2, 1.5, 1.7, 2, 2.5, 3, 3.5, or 4 mm. The foregoing sizes and ranges can represent an average size, for example a number-or weight-average size for a distribution of particle sizes. Alternatively or additionally, the size ranges can represent 1%/99%, 5%/95%, or 10%/90% cut sizes in a cumulative particle size distribution. Alternatively or additionally, the sizes or size ranges can represent sieve or screen sizes for classified particles. Particles that have smaller particle sizes can heat up too quickly (e.g., having a relatively higher specific surface area per unit volume or mass), releasing their volatile content too rapidly removing excessive energy from the arcs in a localized area of the reactor leading to plasma instability and other operational issues. Particles that have larger particle sizes can travel through the reactor too quickly in a top feeding configuration and can have a heating rate that is too slow (e.g., having a relatively lower specific surface area per unit volume or mass) causing them to combust and decompose only partially, reducing the overall carbon conversion. In embodiments, a particle size in a range of about 0.5-2.0 mm can provide a suitable balance between, for example, heating rate and reactor stability.

[0104] Dried biosolids particles can have a spherical shape, a quasi-spherical shape, an irregular shape, other shapes with an aspect ratio of about 1, and combinations thereof.

[0105] Biosolids materials to be fed into the reactor can contain about 40 wt. % to about 80 wt. % of volatile/convertible carbon components (convertible carbon) and/or up to 50 wt. % of ash, for example on a dry-weight or wet-weight basis. In embodiments, the biosolids materials fed to the reactor can contain at least 40, 50, or 60 wt. % and/or up to 60, 70, or 80 wt. % volatile/convertible carbon components. In embodiments, the biosolids materials fed to the reactor can contain at least 1, 2, 5, 10, 15, or 20 wt. % and/or up to 15, 20, 25, 30, 40, or 50 wt. % ash. As used herein and unless specified otherwise, the term volatile/convertible carbon is intended to refer to a mixture of short and long chain hydrocarbons, aromatic hydrocarbons, carbohydrates, lipids, proteins, and other macromolecular combustible organic matter present in biosolids materials. As used herein, the terms volatile carbon, convertible carbon and volatile/convertible carbon should be considered interchangeable. As used herein and unless specified otherwise, ash is intended to refer to a non-volatile and non-combustible material containing mostly inorganic matter including inorganic compounds of different metals, inorganic carbon compounds and elemental carbon including different crystalline and amorphous carbon allotropes.

[0106] The biosolids also can be characterized in terms of its elemental composition, which typically includes at least carbon, hydrogen, nitrogen, sulfur, and oxygen elements. In embodiments, elemental carbon content can be at least 25, 30, 35, or 40 wt. % and/or up to 45, 50, 55, or 65 wt. % on a dry weight basis. In embodiments, elemental hydrogen content can be at least 1, 2, 3, or 5 wt. % and/or up to 7, 8, 9, or 10 wt. % on a dry weight basis. In embodiments, elemental nitrogen content can be at least 1, 2, 3, or 5 wt. % and/or up to 7, 8, 9, or 10 wt. % on a dry weight basis. In embodiments, elemental sulfur content can be at least 0.2, 0.4, 0.6, or 1 wt. % and/or up to 1.2, 1.4, 1.6, or 2 wt. % on a dry weight basis. In embodiments, elemental oxygen content can be at least 10, 15, 20, or 25 wt. % and/or up to 20, 25, 30, or 35 wt. % on a dry weight basis.

[0107] In some embodiments, the reactor can include one or more preheating elements for biosolids material before entering the plasma module(s) of the reactor. In other embodiments, the reactor can be free from such preheating elements. As described above, a typical plasma generating system is arcing between two electrodes within the body of the reactor. A preheating element can be incorporated into the reactor by placing or inserting an additional module at the top (e.g., between the feed port(s) 124 for input material to be processed and first plasma unit or module 16), which additional module uses one, two, three, or more torches to preheat the biosolids before they enter the plasma modules. These torches are different in that the cathode and anode are in the same body producing a short arc over which nitrogen (or other working gas) flows. The nitrogen is heated and ionized by the arc and is used to carry the heat and ions into the reaction vessel.

[0108] The reactor is generally operated at high temperatures and about atmospheric pressure (e.g., about 0.8-1.2 or 0.9-1.1 atm) for input material processing. For example, creation of the electrical arc in the reactor can include forming a localized plasma in the reaction chamber having a temperature of at least 3000 C. (or at least 5000 C.) to which the input material is subjected to combust the biosolids material and more particularly the volatile carbon components in the biosolids material. An upper bound for the reaction temperature is about 2000 C. to about 10000 C. or about 8000 C. to about 10000 C. in the bulk or otherwise near the center of the reaction chamber. During the reaction, the temperature can be about 1500 C. to about 2000 C., or about 1500 C. to about 1700 C. at the reactor wall, based on the reactor construction materials and their ability to withstand high temperatures.

[0109] As described above, the reactor according to the disclosure can be operated to process biosolids materials in a gasifier or gasification mode in which oxygen is present in the reaction chamber thereof, or in a pyrolysis mode in which no or limited oxygen is present in or introduced into the reaction chamber. For example, the reaction chamber can be maintained or operated in an oxidative process mode, such as a fully or partially oxidative state with an oxygen-containing gas fed to the reaction chamber or otherwise present therein during electrical arcing and formation of the processed material. Alternatively, the reaction chamber can be maintained or operated in a pyrolysis (or anaerobic) process mode, such as where no oxygen or limited oxygen is fed to the reaction chamber or otherwise present therein during electrical arcing and formation of the processed material. Some oxygen can still be available for reaction even in pyrolysis mode, for example when the biosolids material contains some elemental oxygen and/or some (liquid) water.

[0110] Operation of the reactor during processing can include feeding one or both of a working gas and/or a reactive gas to the reaction chamber. The working gas can include any suitable gas for plasma formation and reaction component transport, for example a carrier gas or inert/non-reactive gas such as nitrogen or argon. The working gas can be fed to the reaction chamber before and/or during electrical arcing and/or and formation of the processed material. When present, a reactive gas can similarly provide functions of plasma formation and reaction component transport, in addition to providing reactive species for product formation. A suitable reactive gas includes an oxygen-containing gas (e.g., for operation in an oxidative or gasifier mode). The reactive gas can be fed to the reaction chamber before and/or during electrical arcing and/or and formation of the processed material. Examples of oxygen-containing reactive gases include air, oxygen gas, water (e.g., steam), nitrogen oxides (e.g., NOx such as NO, NO.sub.2, N.sub.2O.sub.5, and/or NO.sub.3), and carbon dioxide. The reactive gases can be gaseous byproducts from other industrial processes or otherwise atmospheric contaminants.

[0111] In one aspect of the disclosure, the amount of reactive gas fed to the reactor operating in gasifier mode can be selected in combination with the amount of biosolids materials and volatile carbon content of the biosolids feed material to increase or maximize carbon conversion/CO production. In embodiments, a mixture of different oxygen atom-containing reactive gases can be fed to the reactor. A reactive gas including oxygen (O.sub.2) can be used to not only increase available oxygen atoms for reaction (e.g., resulting in relatively more CO), but its reaction also provides additional energy beyond that supplied by the electrodes, thus increasing biosolids conversion. Other options can similarly increase available oxygen atoms and/or hydrogen atoms for reaction to also increase the relative amount of CO formed (water, carbon dioxide, nitrogen oxides) and/or H.sub.2 formed (water). The reactive gas feed can include water steam or atomized liquid water, for example to drive a hydroxyl shift reaction in situ in the reactor based on desired products and elemental composition of the input material. The hydroxyl shift reaction can form reactive hydrogen (H.Math.) and hydroxyl (HO.Math.) species in the reaction chamber to shift the reaction products toward a desired distribution. The reactions with water and CO.sub.2 to produce CO and H.sub.2 are endothermic. More generally, energy is released during CO formation, if CO.sub.2 or H.sub.2O are reacted with the carbon content of biosolids materials at temperatures above 1000K. For reactions with NOx gases (e.g., NO, NO.sub.2, N.sub.2O.sub.5, and/or NO.sub.3) the energy released is more significant than the CO.sub.2 and H.sub.2O reactions with carbon at all temperatures.

[0112] In embodiments, a working gas substantially free of oxygen can be supplied to the reactor to operate in pyrolysis mode. The amount of working gas fed to the reactor can be selected in combination with the amount of biosolids material and volatile carbon content of the biosolids feed material to increase or maximize carbon conversion.

[0113] As described above, the particular feed flow rates for the reactive gas and the working gas can be selected based on the composition of the biosolids feed and the desired syngas product distribution. In embodiments, the reactive gas can be fed to the reactor in an amount in a range of 1 wt. % to 60 wt. %, or about 1 wt. % to 100 wt. % relative to the biosolids feed compositions (e.g., on a wet-or dry-weight basis), for example at least 1, 2, 5, 10, 15, 20, 25, 30, 35, 40, 50, 60, 70, 80, or 90 wt. % and/or up to 10, 15, 20, 25, 30, 35, 40, 45, 50, 60, 70, 80, 90, 95, or 100 wt. %. In embodiments, the working gas can be fed to the reactor in an amount in a range of 1 wt. % to 20 wt. %, or in a range of 1 wt. % to 100 wt. % relative to the biosolids feed (e.g., on a wet-or dry-weight basis), for example at least 1, 2, 5, 7, 10, 12, 20, 30, 40, 50, 60, 70, 80, 90 wt. % and/or up to 5, 7, 10, 12, 15, 17, 20, 30, 40, 50, 60, 70, 80, 90, 95, or 100 wt. %. The foregoing ranges are illustrative, and the reactive gas feed rate and/or the working gas feed rate can be higher or otherwise different in various embodiments. For example, the working gas and the reactive gas feed amount can be higher than these ranges depending on feed composition, moisture content, desirable processing conditions, etc. In embodiments, the reactive gas, working gas, and input material are fed simultaneously to the reactor. In embodiments, the reactive gas, working gas, and input materials are fed to the reactor in sequence.

[0114] The modular design of the reactor facilitates processes that have a desired process capacity and volatile carbon conversion. In particular, given the variable amount of water and volatile carbon content in the biosolids materials that can be processed according to the disclosed method, different input or feed materials can require different processing times. In cases where a higher amount of biosolids materials needing to be processed, additional plasma modules or units can be stacked or other added to a reactor unit to increase the residence or exposure time of an input material to plasma for processing. For example, the plasma reactor 10 in FIG. 1 includes four plasma units 16 stacked and aligned in series; an extension of the gasifier 10 in FIG. 1 could include one, two, three, or more plasma units 16 stacked and aligned in series (not shown) to increase fluorocarbon conversion, mineralization, etc. Alternatively or additionally, the number of electrode pairs could be increased in one or more of the plasma modules or units. For example, the plasma unit 16 in FIG. 2 includes three pairs of electrode assemblies 42; an extension of the plasma unit 16 in FIG. 2 could include one, two, three, or more additional electrode pairs (not shown) to increase biosolids conversion, etc., such as through the access ports 40 shown in FIG. 2 that do not contain electrode assemblies 42 therein.

[0115] The reactor provides a relatively energy-efficient means to process biosolids, whether in oxidative mode or pyrolysis mode. In embodiments, total power supplied to the electrodes (e.g., across all electrode pairs combined) relative to biosolids feed rate can be in a range of 0.5 (kW.Math.hr)/kg to 4 (kW.Math.hr)/kg (e.g., reflecting total power supplied to the electrodes in kW relative to biosolids feed rate in kg/hr). For example, total power supplied to the electrodes can be at least 0.5, 0.7, 0.9, 1.1, 1.4, 1.7, or 2 (kW.Math.hr)/kg and/or up to 1.8, 2, 2.3, 2.7, 3, 3.5, 4 (kW.Math.hr)/kg relative to biosolids feed rate. Particularly suitable relative power rates can be about 1.7-2.7 (kW.Math.hr)/kg for pyrolysis and about 1.1-2 (kW.Math.hr)/kg for gasification.

[0116] In some embodiments, the processed material exiting the reactor can be fed and further reacted in a water-gas shift reactor. Water-gas shift reactors, as well as suitable catalysts and reaction conditions for same, are generally known in the art and can be used to increase hydrogen gas content of the processed material by converting water and carbon monoxide to hydrogen and carbon dioxide (i.e., according to the water-gas shift equilibrium reaction). In some embodiments, the processed material exiting the reactor can be used for any desired downstream purpose without being treated in a water-gas shift reactor. For example, when the biosolids feed material contains an appreciable amount of water (about 20-30 wt. % or more), in situ plasma cracking of biosolids water content to H.Math. and HO.Math. radicals can increase the H2 content of as-produced syngas from the reactor without the need for a downstream water-gas shift reactor.

[0117] In another aspect, the gases in the processed material, for example hydrogen and carbon monoxide with or without an upstream water-gas shift reaction, are reacted to form a fuel, e.g., a low-carbon or sustainable fuel such as methanol, a light hydrocarbon containing up to 3 carbon atoms (e.g., an alkane, an alkene, an alkyne), diesel, sustainable aviation fuel (SAF) without CO.sub.2 or other greenhouse gas emissions. For example, the processed material can be fed to a methanol production reactor. Methanol production reactors with suitable catalyst, reactor vessel, etc. are known in the art, and they perform a variety of chemical reactions to produce methanol, typically from syngas. Representative reactions for catalytic conversion (e.g., with catalysts including one or more of copper, zinc, aluminum, magnesium, and oxides thereof) from syngas/platform gas components include 2 H.sub.2+CO.fwdarw.CH.sub.3OH and 3 H.sub.2+CO.sub.2.fwdarw.CH.sub.3OH+H.sub.2O. Catalytic oxidation of methane (e.g., in the platform gas) to form methanol is also possible. In other embodiments, the processed material can be fed to one or more of a reverse water gas shift (rWGS) reactor and a Fischer-Tropsch (FT) reactor to provide a heavier hydrocarbon gas stream as a fuel. The rWGS reactor can perform a reverse water gas shift reaction favoring formation of additional carbon monoxide and water relative to that in the reactor output, for example to adjust the H.sub.2:CO ratio to a desired value/range for a subsequent FT process in which an (average) carbon number of the resulting hydrocarbons correlate to the H.sub.2:CO molar ratio in the FT reactor feed. FT and rWGS reactors with suitable catalyst, reactor vessel, etc. are known in the art.

[0118] A biosolids material processed according to methods of the disclosure can form a processed material comprising a gas phase. The gas phase can be syngas containing about 10 to about 90% or about 25-60% hydrogen gas (H.sub.2) and about 10 to about 90% or 20-50% carbon monoxide (CO), optionally with to 2% or so each of water (H.sub.2O) and carbon dioxide (CO.sub.2), and the bulk of the remainder nitrogen gas (N.sub.2) or other inert working gas (e.g., mol. % or vol. %.). In embodiments, the gaseous product can include at least 20, 25, 30, 35, or 40% and/or up to 30, 35, 40, 45, 50, 55, or 60% H2. In embodiments, the gaseous product can include at least 20, 25, 30, 35, or 40% and/or up to 30, 35, 40, 45, 50, 55, or 60% CO. The hydrogen gas to carbon monoxide ratio in the gas phase can be about 100:1 to 1:100, 10:1 to 1:10, or 2:1 to 1:1. For example, the H.sub.2/CO ratio can be about 2:1, or about 1.7:1, or about 1.5:1, or about 1.2:1, or about 1.1:1 or about 1:1 or any values therebetween or ranges defined by those values. More generally, the H.sub.2/CO ratio can be at least 100:1, 80:1, 60:1, 50:1, 40:1, 30:1, 20:1, 10:1, 5:1, or 2:1 and up to 1:100, 1:80, 1:60, 1:50, 1:40, 1:30, 1:20, 1:10, 1:5, or 1:1, or about 100:1, 90:1, 80:1, 70:1, 60:1, 50:1, 40:1, 30:1, 20:1, 10:1, 5:1, 3:1, 2:1, 1.5:1, 1:1, 1:1.5, 1:2, 1:3, 1:5, 1:10, 1:20, 1:30, 1:40, 1:50, 1:60, 1:70, 1:80, 1:90, 1:100, or any values therebetween or ranges defined by those values. The H.sub.2/CO ratios can vary depending on the composition of the working and/or reactive gas and the oxygen and water content in the biosolids materials and can be adjusted downstream to a particularly desirable value. For example, steam or a high-water content biosolids material can be fed to the reactor to increase the hydrogen gas concentration in the processed material. In embodiments, the foregoing H.sub.2/CO ratios can represent a product distribution exiting the plasma reactor or exiting a downstream unit operation (e.g., a water-gas shift reactor or separator to further adjust the H.sub.2/CO ratio).

[0119] The gas phase in the processed material can further comprise water (H.sub.2O) and carbon dioxide (CO.sub.2) in an amount up to 2% or about 10% (e.g., mol. % or vol. %.). In embodiments, the gaseous product can include at least 0.0001, 0.001, 0.01, 0.1, or 1% and/or up to 0.1, 0.2, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10% H.sub.2O and/or CO.sub.2. For example, the combined amount of H.sub.2O and CO.sub.2 in the gas phase of the processed material can be about 0.001%, or about 0.1%, or about 1%, or about 1.1%, or about 1.2%, or about 1.3%, or about 1.4%, or about 1.5%, or about 1.6%, or about 1.7%, or about 1.8%, or about 1.9% or up to about 2% (e.g., mol. % or vol. %.). In embodiments, the combined amount of H.sub.2O and CO.sub.2 in the gas phase of the processed material can be up to or about 0.01, 0.1, 1, 1.1, 1.5, 2, 3, 4, 5, 6, 7, 8, 9 or up to about 10% (e.g., mol. % or vol. %.). Similar upper bounds can individually or collectively apply to other potential byproducts (e.g., components other than H.sub.2, CO, H.sub.2O, CO.sub.2, and/or working gas), even though they would be preferably or typically absent in many cases.

[0120] Still further, the gas phase in the processed material can contain nitrogen or other inert working gas. The amount of nitrogen in the gas phase can be at least 80% (e.g., mol. % or vol. %.) of the gas phase components other than H.sub.2, CO, CO.sub.2, and H.sub.2O. In embodiments, at least 80, 85, 90, 95, 98, or 99% and/or up to 95, 98, 99, or 100% of the remaining gas is nitrogen or other inert working gas.

[0121] A biosolids material processed according to methods of the disclosure can form a processed material further including tar-free ash. Advantageously, the processed material can include solid nanoparticles, such as one or more of nanosized ash (or char) and carbon nanoparticles. The high energy and rapid conversion process in the disclosed reactor rapidly vaporizes the feed material, which then condenses in a very rapid nucleation process to form nano-sized particles from inorganic and other ash material originally present in the biosolids feed as well as carbon nanoparticles formed in the reactor from biosolids carbon content (e.g., biosolids carbon not converted to CO or CO.sub.2). The nanoparticles can have a particle size, for example an average particle size, in a range of about 5 nm to about 100 nm or about 10 nm to about 50 nm, for example at least about 5, 7, 10, 12, 15, 20, 25, 30, or 40 nm and/or up to 20, 25, 30, 35, 40, 50, 60, 80, or 100 nm. The foregoing sizes and ranges can represent an average size, for example a number-or weight-average size for a distribution of particle sizes. Alternatively or additionally, the size ranges can represent 1%/99%, 5%/95%, or 10%/90% cut sizes in a cumulative particle size distribution. The nanoparticles produced in the disclosed reactor are several orders of magnitude smaller than the carbonaceous ash fraction produced by a conventional gasifier, which is more granular and typically ranges from about 500 to about 1000 microns. The amount of nanoparticles or ash present in the processed material can vary between about 15 wt. % to 50 wt. % (e.g., relative to total product gases and ash combined). The final nanoparticle content in the processed material depends on the amount of ash in the biosolids feed (e.g., which is not otherwise converted) plus any carbon nanoparticles formed in the reactor from elemental biosolids carbon. The nanoparticles can be separated from the processed gas stream by any suitable method, such as vortex flow, filtration, electro-precipitation, cold wall deposition, wet scrubbing, etc. The resulting nanoparticles from the processed material are particularly useful as an additive, reinforcement, or filler in various compositions. For example, the nanoparticles can be used as a colorant, reinforcer and/or filler in rubber, cement, electromagnetic field-blocking materials, and other composites. The enhanced electrical conductivity of carbon nanoparticles, over other carbon allotropes can make carbon nanoparticle rich ash a suitable additive for cathodes and anodes in lithium-ion batteries.

[0122] The methods according to the disclosure are characterized by their ability to convert volatile carbon to syngas. Suitable target values for carbon conversion can be at least about 90%, although lower conversion values may be obtained in various embodiments while still providing a useful syngas production process, for example depending on the nature of the biosolids feed and/or any reactive gas feed. For an oxidative/gasification process, carbon conversions are typically at least about 80% in most cases. For a pyrolysis process, the carbon conversion may depend on the amount of oxygen, volatile carbon, and water present in the biosolid material and might be as low as 40%. Lower carbon conversion values can be desirable, for example when it is desired to form a relatively larger fraction of carbon nanoparticles in the processed material (e.g., to serve as a suitable reinforcement or filler material as described above). Thus, in various embodiments, carbon conversion can be at least 40, 50, 60, 70, 80, 90, or 95% and/or up to 50, 60, 70, 80, 90, 95, 98, or 99%. Carbon conversion values are generally expressed relative to volatile/convertible carbon content of the biosolids feed (i.e., excluding ash content of the feed, which would not be converted to a syngas component or other useful gaseous product). Accordingly, the carbon conversion can reflect the fraction of elemental carbon in the original biosolids material that is converted to carbon monoxide (i.e., primary syngas product) and/or carbon dioxide (i.e., reactor byproduct). Similarly, the complement of the carbon conversion can reflect the fraction of elemental carbon in the original biosolids material that is converted to carbon nanoparticles. For example, at least 1, 2, 5, 10, 20, 30, 40, or 50% and/or up to 5, 10, 20, 30, 40, 50, or 60% of elemental carbon in the original biosolids material can be converted to carbon nanoparticles.

[0123] According to methods of the disclosure, the process can be run in a batch operation or more preferably in a continuous process operation.

[0124] The following includes a summary of the disclosed methods for processing a material as well as suitable reactors or gasifiers that can be used to perform the disclosed methods.

[0125] In an aspect, the disclosure relates to a method of processing a material, the method comprising: receiving an input material to be processed within a reaction chamber, the input material comprising a biosolids material; energizing one or more sets of electrodes, each set of electrodes including an anode electrode and a cathode electrode, each anode electrode and cathode electrode having an electrode tip exposed to the reaction chamber; and creating an electrical arc between the anode electrode tip and the cathode electrode tip within the reaction chamber to subject at least some of the input material to electrical arcing, thereby reacting at least a portion of the biosolids material and forming a processed material comprising hydrogen (H.sub.2) and carbon monoxide (CO).

[0126] In a refinement, the method further comprises: creating a plasma in a plasma torch; and injecting the plasma from the plasma torch into the reaction chamber to expose at least some of the input material to the plasma from the plasma torch when forming the processed material.

[0127] In a refinement, the biosolids material is in the form of dried biosolids particles. For example, the biosolids particles can have an average particle size in a range of about 0.3 mm to about 4.0 mm or about 0.5 mm to about 2.0 mm.

[0128] In a refinement, the method further comprises: drying the biosolids material prior to feeding the input material to the reaction chamber.

[0129] In a refinement, the biosolids material has a water content of not more than 20 wt. %.

[0130] In a refinement, the method further comprises: feeding the processed material to a water-gas shift reactor (e.g., to increase H.sub.2 content/reduce CO content of as-produced syngas from the reactor).

[0131] In a refinement, the biosolids material has a water content of at least 20 wt. %. In a further refinement, the processed material is not further treated in a water-gas shift reactor (e.g., where plasma cracking of biosolids H.sub.2O content to H.Math. and HO.Math. radicals can increase H.sub.2 content of as-produced syngas from the reactor without the need for a downstream water-gas shift reactor).

[0132] In a refinement, the biosolids material comprises undigested biosolids.

[0133] In a refinement, the biosolids material comprises digested biosolids.

[0134] In a refinement, the biosolids material comprises: 5 wt. % to 95 wt. % digested biosolids relative to total biosolids; and 5 wt. % to 95 wt. % undigested biosolids relative to total biosolids.

[0135] In a refinement, the method further comprises: feeding a working gas to the reaction chamber.

[0136] In a refinement, the method further comprises: feeding a reactive gas to the reaction chamber. In a further refinement, the reactive gas comprises one or more oxygen atoms. In a further refinement, the reactive gas is selected from the group consisting of air, oxygen gas, water (e.g., steam), carbon dioxide, nitrogen oxides, and combinations thereof.

[0137] In a refinement, the method comprises: operating the reaction chamber in an oxidative or gasification process mode.

[0138] In a refinement, the method comprises: operating the reaction chamber in a pyrolysis process mode.

[0139] In a refinement, the method comprises: supplying power to the electrodes in an amount in a range of 0.5 (kW.Math.hr)/kg to 4 (kW.Math.hr)/kg relative to biosolids feed rate, for example about 1.7-2.7 (kW.Math.hr)/kg for pyrolysis and about 1.1-2 (kW.Math.hr)/kg for gasification.

[0140] In a refinement, creating the electrical arc comprises forming a localized plasma in the reaction chamber having a temperature of at least 3000 C. to which the input material is subjected.

[0141] In a refinement, creating the electrical arc comprises operating the reaction chamber at about atmospheric pressure.

[0142] In a refinement, the processed material comprises a gas phase (e.g., syngas product phase) containing 25-60% hydrogen gas (H.sub.2) and 20-50% carbon monoxide (CO) (e.g., mol. % or vol. %.). In a further refinement, the gas phase further comprises at least one of water (H.sub.2O) and carbon dioxide (CO.sub.2) in an amount up to 2% (e.g., mol. % or vol. %.). In a further refinement, the gas phase further comprises nitrogen (N.sub.2) (or other non-reactive working gas(es) fed to the reactor) in an amount that is at least 80% of the gas phase that is other than H.sub.2, CO, CO.sub.2, and H.sub.2O. In a further refinement, a ratio of hydrogen gas: carbon monoxide in the gas phase is in a range of 2:1 to 1:1, or about 1.2:1 (vol/vol or mol/mol).

[0143] In a refinement, the method comprises reacting the biosolids material with a carbon conversion of at least 40%.

[0144] In a refinement, the method comprises reacting the biosolids material with a carbon conversion of at least 90%.

[0145] In a refinement, the processed material comprises nanoparticles selected from the group consisting of nanosized ash (or char), carbon nanoparticles, and combinations thereof.

[0146] In a further refinement, the nanoparticles have an average particle size in a range of about 5 nm to about 100 nm.

[0147] In a refinement, the processed material is free from tar.

[0148] In a refinement, the method comprises processing the material in a continuous process operation.

[0149] In a refinement, the method comprises processing the material in a batch process operation.

[0150] The disclosed methods can be performed in the reactors as generally disclosed herein, for example a plasma or ionic reactor or gasifier, including representative reactors or gasifiers as summarized below.

[0151] In a first reactor or gasifier aspect, a reactor or gasifier comprises: an input for receiving a material to be processed; an output; one or more plasma units, each plasma unit including; an outer wall that defines an internal reaction zone; and one or more sets of electrode assemblies, wherein each set of electrode assemblies includes an anode electrode and a cathode electrode, wherein each of the anode electrode and the cathode electrode includes an electrode tip exposed to the reaction zone; wherein each set of electrode assemblies is connected to a power supply for energizing the anode electrode and the cathode electrode with a power signal to cause arcing in the reaction zone between the anode electrode and the cathode electrode; wherein the one or more plasma units are disposed between the input and the output so that the reaction zones of the one or more plasma units define a reaction chamber such that the material to be processed flows through the reaction chamber from the input to the output and is subject to the arcing produced by the one or more sets of electrode assemblies in the one more plasma units; and a plasma torch disposed adjacent the reaction chamber and having an output that emits plasma into the reaction chamber.

[0152] In a refinement, the plasma torch is disposed near the input.

[0153] In a refinement, the plasma torch is disposed near the output.

[0154] In a refinement, the reaction chamber has a longitudinal axis extending from the input to the output and wherein the plasma torch is oriented to direct the plasma in a stream longitudinally into the reaction chamber.

[0155] In a refinement, the reactor or gasifier includes a plurality of plasma units and wherein the plasma torch is oriented to direct the plasma into the reaction zone of at least two of the plurality of plasma units.

[0156] In a refinement, the plasma torch is disposed in one of the one or more plasma units and extends through the outer wall of the one of the one or more plasma units to direct plasma radially into the reaction zone of the one of the one or more plasma units.

[0157] In a refinement, each of the electrode assemblies includes one or more working gas passageways and a working gas outlet that conducts a working gas into the reaction zone of one of the plasma units. In a further refinement, the working gas emitted via the one or more electrode assemblies can be subjected to one or more arcs within the reaction zone of the one of the plasma units to form a plasma.

[0158] In a refinement, the plasma emitted by the plasma torch ignites one or more arcs between the anode electrode and the cathode electrode of at least one set of electrode assemblies.

[0159] In a refinement, each of the one or more plasma units is circular in cross section defining a cylindrical reaction zone. In a further refinement, the gasifier or reactor can include a plurality of plasma units stacked longitudinally to define an elongated cylindrical reaction chamber. In a further refinement, each of the plurality of plasma units can include two or more sets of electrode assemblies. In a further refinement, the plasma torch can emit a plasma flame that passes through the reaction zone of at least two of the plasma units to interact with one or more arcs produced by the electrode assemblies of each of the at least two plasma units.

[0160] In a second reactor or gasifier aspect, a reactor or gasifier comprises: a reaction chamber formed by a continuous outer wall extending between a first open end and a second open end defining a longitudinal axis between the first open end and the second open end; at least one set of electrodes extending through the outer wall between the first open end and the second open end into the reaction chamber, each set of electrodes including an anode electrode and a cathode electrode, wherein each of the anode electrode and the cathode electrode includes an electrode tip and wherein each set of electrodes is connected to a power supply for energizing the anode electrode and the cathode electrode with a power signal to cause arcing in the reaction chamber between the anode electrode tip and the cathode electrode tip; and a plasma torch disposed adjacent the reaction chamber and having an output that emits plasma into the reaction chamber.

[0161] In a refinement, the plasma torch emits plasma as a plasma flame into the reaction chamber.

[0162] In a refinement, the anode electrode and the cathode electrode extend into the reaction chamber in a first plane perpendicular to the longitudinal axis, and wherein the plasma torch is disposed perpendicularly to the first plane to emit the plasma into the reaction chamber perpendicularly to the first plane.

[0163] In a refinement, the anode electrode and the cathode electrode extend into the reaction chamber in a first plane perpendicular to the longitudinal axis, and wherein the plasma torch is disposed to emit the plasma into the reaction chamber in a direction parallel to the first plane.

[0164] In a refinement, the anode electrode and the cathode electrode extend into the reaction chamber in a first plane perpendicular to the longitudinal axis, and wherein the plasma torch is disposed to emit the plasma into the reaction chamber in a direction that is parallel to and within the first plane.

[0165] In a refinement, the anode electrode and the cathode electrode extend into the reaction chamber in a first plane perpendicular to the longitudinal axis, and wherein the plasma torch is disposed to emit the plasma into the reaction chamber in a direction that intersects the first plane at a non-zero angle.

[0166] In a refinement, the reactor or gasifier further includes a material input and a material output, wherein the at least one set of electrodes is disposed so that the anode electrode and the cathode electrode of the set of electrodes are disposed laterally across the reaction chamber and wherein the plasma torch is oriented to direct the plasma in a stream longitudinally into the reaction chamber. In a further refinement, the reaction chamber can include a plurality of plasma units, each plasma unit including an outer wall defining a reaction zone within the confines of the outer wall and at least one set of electrodes, and the plasma units can be stacked on each other to align the outer walls of the plasma units so that the reaction zones of the plurality of plasma units form the reaction chamber. In a further refinement, the plasma torch is oriented to direct the plasma into the reaction zone of at least two of the plurality of plasma units.

[0167] In a refinement, the reaction chamber includes one or more cylindrical plasma units formed by a cylindrical outer wall, and wherein the plasma torch is disposed in one of the one or more plasma units and extends through the outer wall of the one of the one or more plasma units to direct plasma radially into the reaction zone of the one of the one or more plasma units.

[0168] In a refinement, one or more of the electrodes includes one or more working gas passageways and a working gas outlet that conducts a working gas into the reaction chamber.

[0169] In a further refinement, the working gas emitted via the one or more electrodes can be subjected to one or more arcs within the reaction chamber during operation of the gasifier.

[0170] In a refinement, the plasma emitted by the plasma torch ignites one or more arcs between the electrodes of a set of electrodes during operation of the gasifier.

[0171] In a third reactor or gasifier aspect, a reactor or gasifier comprises: an input for receiving a material to be processed; an output; one or more plasma units disposed between the input and the output, each plasma unit including; an outer wall that defines an internal reaction zone; and a plurality of sets of electrodes mounted in the outer wall, wherein each set of electrodes includes; an anode electrode with an anode electrode tip exposed to the reaction zone, and a cathode electrode with a cathode electrode tip exposed to the reaction zone; wherein each of the sets of electrodes is connected to a power supply for energizing the anode electrode and the cathode electrode with a power signal to cause arcing in the reaction zone between the anode electrode tip and the cathode electrode tip; and wherein the individual electrodes of the plurality of sets of electrodes are disposed in an offset manner around the outer wall so that the every adjacent pair of electrodes includes an anode electrode and a cathode electrode.

[0172] In a refinement, the anode electrode and the cathode electrode of at least one of the sets of electrodes are offset from one another around the outer wall at an angle that is less than 180 degrees.

[0173] In a refinement, the anode electrode and the cathode electrode of at least one of the sets of electrodes are offset from one another around the outer wall by an acute angle.

[0174] In a refinement, the anode electrode and the cathode electrode of at least one of the sets of electrodes are offset from one another around the outer wall by an obtuse angle.

[0175] In a refinement, the anode electrode and the cathode electrode of at least one of the sets of electrodes are offset from one another around the outer wall by a 90 degree angle.

[0176] In a refinement, the anode electrode and the cathode electrode of a first one of the sets of electrodes are offset from one another around the outer wall at a first angle less than 180 degrees and wherein the anode electrode and the cathode electrode of a second one of the sets of the electrodes are offset from one another around the outer wall by a second angle different than the first angle.

[0177] In a refinement, the anode electrode and the cathode electrode of a first one of the sets of electrodes are offset from one another around the outer wall by a first angle less than 180 degrees and wherein the anode electrode and the cathode electrode of a second one of the sets of electrodes are offset from one another around the outer wall by 180 degrees.

[0178] In a refinement, the plurality of sets of electrodes includes three sets of electrodes, wherein the anode electrode and the cathode electrode of a first one of the three sets of electrodes are offset from one another around the outer wall by 180 degrees and wherein the anode electrode and the cathode electrode of a second and a third one of the three sets of electrodes are offset from one another around the outer wall by 60 degrees.

[0179] In a refinement, the plurality of sets of electrodes includes three sets of electrodes, and wherein the anode electrode and the cathode electrode each of the three sets of electrodes are offset from one another around the outer wall by 60 degrees.

[0180] In a refinement, the plurality of sets of electrodes includes four sets of electrodes, and wherein the anode electrode and the cathode electrode of at least two of the four sets of the electrodes are offset from one another around the outer wall by 135 degrees.

[0181] In a refinement, the plurality of sets of electrodes includes four sets of electrodes, and wherein the anode electrode and the cathode electrode of at least two of the four sets of the electrodes are offset from one another around the outer wall by 45 degrees.

[0182] In a refinement, the gasifier or reactor further includes a plasma torch disposed adjacent the reaction zone of at least one of the one or more plasma units and having an output that emits plasma into the reaction zone of the at least one of the one or more plasma units. In a further refinement, the plasma torch can be disposed near the input. In a further refinement, the reaction zones of the one or more plasma units can define a reaction chamber having a longitudinal axis extending from the input to the output and the plasma torch can be oriented to direct the plasma in a stream longitudinally into the reaction chamber. In a further refinement, the plasma torch can be disposed in one of the one or more plasma units and extends through the outer wall of the one of the one or more plasma units to direct plasma radially into the reaction zone of the one of the one or more plasma units.

[0183] In a refinement, at least one of the sets of electrodes of one of the one or more plasma units includes an electrode assembly that includes one or more working gas passageways and a working gas outlet that conduct a working gas into the reaction zone of the one of the one or more plasma units.

[0184] In a refinement, the outer wall of one of the one or more plasma units is circular in cross section to define a cylindrical reaction zone for the one of the one or more plasma units.

[0185] In a fourth reactor or gasifier aspect, a reactor or gasifier comprises: an input for receiving a material to be processed; an output; one or more plasma units disposed between the input and the output, each plasma unit including; an annular outer wall that defines an internal reaction zone; and a plurality of sets of electrodes mounted in the annular outer wall, wherein each set of electrodes includes; an anode electrode with an anode electrode tip exposed to the reaction zone, and a cathode electrode with a cathode electrode tip exposed to the reaction zone; wherein each set of electrodes is connected to a power supply for energizing the anode electrode and the cathode electrode with a power signal to cause arcing in the reaction zone between the anode electrode tip and the cathode electrode tip; and wherein the anode electrode and the cathode electrode of at least one of the sets of electrodes are offset from one another around the outer annular wall at an angle that is less than 180 degrees.

[0186] In a refinement, the anode electrode and the cathode electrode of at least one of the sets of electrodes are offset from one another around the annular outer wall by an acute angle.

[0187] In a refinement, the anode electrode and the cathode electrode of at least one of the sets of the electrodes are offset from one another around the annular outer wall by an obtuse angle.

[0188] In a refinement, the anode electrode and the cathode electrode of at least one of the sets of electrodes are offset from one another around the annular outer wall by a 90-degree angle.

[0189] In a refinement, the anode electrode and the cathode electrode of a first one of the sets of electrodes are offset from one another around the annular outer wall at a first angle that is less than 180 degrees and wherein the anode electrode and the cathode electrode of a second one of the sets of electrodes are offset from one another around the annular outer wall by a second angle different than the first angle.

[0190] In a refinement, the anode electrode and the cathode electrode of a first one of the sets of electrodes are offset from one another around the annular outer wall by a first angle less than 180 degrees and wherein the anode electrode and the cathode electrode of a second one of the sets of electrodes are offset from one another around the annular outer wall by an angle of 180 degrees.

[0191] In a refinement, the plurality of sets of electrodes includes three sets of electrodes, wherein the anode electrode and the cathode electrode of a first one of the three sets of electrodes are offset from one another around the annular outer wall by 180 degrees and wherein the anode electrode and the cathode electrode of a second one and of a third one of the three sets of electrodes are offset from one another around the annular outer wall by 60 degrees.

[0192] In a refinement, the plurality of sets of electrodes includes three sets of electrodes, and wherein the anode electrode and the cathode electrode each of the three sets of electrodes are offset from one another around the annular outer wall by 60 degrees.

[0193] In a refinement, the plurality of sets of electrodes includes four sets of electrodes, and wherein the anode electrode and the cathode electrode of at least two of the four sets of electrodes are offset from one another around the annular outer wall by 135 degrees.

[0194] In a refinement, the plurality of sets of electrodes includes four sets of electrodes, and wherein the anode electrode and the cathode electrode of at least two of the four sets of the electrodes are offset from one another around the annular outer wall by 45 degrees.

[0195] In a refinement, the gasifier or reactor further includes a plasma torch disposed adjacent the reaction zone of at least one of the one or more plasma units and having an output that emits plasma into the reaction zone of the at least one of the one or more plasma units. In a further refinement, the plasma torch is disposed near the input. In a further refinement, the reaction zones of the one or more plasma units can define a reaction chamber having a longitudinal axis extending from the input to the output and the plasma torch can be oriented to direct the plasma in a stream longitudinally into the reaction chamber. In a further refinement, the gasifier or reactor can include a plurality of plasma units and wherein the plasma torch is oriented to direct the plasma into the reaction zone of at least two of the plurality of plasma units. In a further refinement, the plasma torch can be disposed in one of the one or more plasma units and extends through the annular outer wall of the one of the one or more plasma units to direct plasma radially into the reaction zone of the one of the one or more plasma units. In a further refinement, at least one of the sets of electrodes of one of the one or more plasma units can include an electrode assembly that includes one or more working gas passageways and a working gas outlet that conduct a working gas into the reaction zone of the one of the one or more plasma units.

[0196] In a refinement, the one or more plasma units are disposed between the input and the output so that the reaction zones of each of the one or more plasma units define a reaction chamber such that the material to be processed flows through the reaction chamber from the input to the output and is subject to the arcing produced by the plurality of sets of electrodes in the one or more plasma units.

[0197] In a refinement, the individual electrodes of the plurality of sets of electrodes in the one or more plasma units are disposed in an offset manner around the outer annular wall so that the every adjacent pair of electrodes includes an anode electrode and a cathode electrode.

[0198] In a fifth reactor or gasifier aspect, a reactor or gasifier comprises: an input for receiving a material to be processed; an output; one or more plasma units disposed between the input and the output, each plasma unit including; an outer wall that defines an internal reaction zone; and one or more sets of electrode assemblies, wherein each set of electrode assemblies includes, a first electrode assembly having, (1) an anode electrode with an anode electrode tip exposed to the reaction zone, (2) a first working gas passageway, (3) a first working gas exit exposed to the reaction zone; and (4) a first set of spiral grooves that spiral in a first circular direction disposed on a first electrode assembly surface exposed to a working gas that causes a first working gas to leave the first working gas exit in a first vortex; and a second electrode assembly having, (1) a cathode electrode with a cathode electrode tip exposed to the reaction zone, (2) a second working gas passageway, (3) a second working gas exit exposed to the reaction zone, and (4) a second set of spiral grooves that spiral in a second circular direction disposed on a second electrode assembly surface exposed to the working gas that causes a second working gas to leave the working gas exit in a second vortex; wherein each of the sets of electrode assemblies is connected to a power supply for energizing the anode electrode and the cathode electrode with a power signal to cause arcing in the reaction zone between the anode electrode tip and the cathode electrode tip in the presence of the first working gas and second working gas both travelling in a vortex.

[0199] In a refinement, the first circular direction and the second circular direction are different circular directions.

[0200] In a refinement, the first circular direction is one of clockwise or counter-clockwise and the second circular direction is the other one of clockwise or counter-clockwise.

[0201] In a refinement, the first electrode assembly is disposed directly across the reaction zone from the second electrode assembly so that a line from the anode electrode tip to the cathode electrode tip bisects the reaction zone.

[0202] In a refinement, the first electrode assembly surface is an electrode core and the second electrode assembly surface is an electrode core.

[0203] In a refinement, the first electrode assembly surface is an interior surface of the first working gas passageway and the second electrode assembly surface is an interior surface of the second working gas passageway.

[0204] In a refinement, the first electrode assembly surface is one of an electrode core or an interior surface of the first working gas passageway and the second electrode assembly surface the other one of an electrode core and an interior surface of the second working gas passageway.

[0205] In a refinement, the first set of grooves has a first pitch and the second set of grooves has a second pitch different than the first pitch.

[0206] In a refinement, the first set of grooves and the second set of groove have the same pitch.

[0207] In a refinement, the outer wall forms a rectangular reaction zone.

[0208] In a refinement, the outer wall forms a cylindrical reaction zone.

[0209] In a refinement, the outer wall forms a tubular reaction zone with the electrode assembles of a set of electrode assemblies being disposed at the tubular ends.

[0210] In a sixth reactor or gasifier aspect, a reactor or gasifier comprises: an input for receiving a material to be processed; an output; one or more plasma units disposed between the input and the output, each plasma unit including; an annular outer wall that defines a cylindrical internal reaction zone; and a plurality of sets of electrode assemblies disposed through the annular outer wall, wherein each set of electrode assemblies includes, a first electrode assembly having an anode electrode with an anode electrode tip exposed to the reaction zone, and a second electrode assembly having a cathode electrode with a cathode electrode tip exposed to the reaction zone, and wherein each of the first and second electrode assemblies further includes, (1) a working gas passageway, (2) a working gas exit exposed to the reaction zone; and (3) a set of spiral grooves on an electrode assembly surface exposed to a working gas that causes a working gas to leave the working gas exit in a vortex; wherein each of the sets of electrode assemblies is connected to a power supply for energizing the anode electrode and the cathode electrode with a power signal to cause arcing in the reaction zone between the anode electrode tip and the cathode electrode tip of the set of electrode assemblies; and wherein the sets of electrode assemblies are disposed around the annular outer wall of the plasma unit so as to create a plurality of sets of oppositely disposed electrode assemblies, with each set of oppositely disposed electrode assemblies includes two electrode assemblies from the same set of electrode assemblies disposed directly across the reaction zone from each other or includes two electrode assemblies from different sets of electrode assemblies disposed directly across the reaction zone from each other.

[0211] In a refinement, at least one of the sets of oppositely disposed electrode assemblies includes a first set of grooves in a first one of the oppositely disposed electrode assemblies that causes the working gas to flow in a first circular direction and includes a second set of grooves in a second one of the oppositely disposed electrode assemblies that causes the working gas to flow in a second circular direction different than the first circular direction.

[0212] In a further refinement, the first circular direction can be one of clockwise or counter-clockwise and the second circular direction can be the other one of clockwise or counter-clockwise.

[0213] In a refinement, the electrode assembly surface of a first one of the electrode assemblies of a particular set of oppositely disposed electrode assemblies is an electrode core and the electrode assembly surface of a second one of the electrode assemblies of the particular set of oppositely disposed electrode assemblies is an electrode core.

[0214] In a refinement, the electrode assembly surface of a first one of the electrode assemblies of a particular set of oppositely disposed electrode assemblies is an interior surface of the fluid gas passageway and wherein the electrode assembly surface of a second one of the electrode assemblies of the particular set of oppositely disposed electrode assemblies is an interior surface of the fluid gas passageway.

[0215] In a refinement, the electrode assembly surface of a first one of the electrode assemblies of a particular set of oppositely disposed electrode assemblies is an interior surface of the fluid gas passageway and wherein the electrode assembly surface of a second one of the electrode assemblies of the particular set of oppositely disposed electrode assemblies is an electrode core.

[0216] In a refinement, the set of grooves of a first one of the electrode assemblies of a particular set of oppositely disposed electrode assemblies and the set of grooves of a second one of the electrode assemblies of the particular set of oppositely disposed electrode assemblies have the same pitch.

[0217] U.S. Publication No. 2023/0166227 is incorporated herein by reference, and it includes disclosure related to reactor or gasifier embodiments that can be used with the disclosed methods herein.

[0218] Although the presently described jet and plasma arc systems can be embodied in many ways, only some exemplary embodiments have been selected for the purposes of illustration and discussion. Moreover, it will be understood that the embodiments of the present invention that are illustrated and described herein are merely exemplary and that a person skilled in the art can make many variations to those embodiments. All such embodiments are intended to be included within the scope of the present invention as defined by the claims.

EXAMPLES

[0219] The following examples are provided for illustration and are not intended to limit the scope of the invention. In general, biosolids materials were treated in a plasma or ionic reactor with 1 to 3 arc modules and 4 to 12 pairs of electrodes, including 3 plasma torches on top of the arc modules. The power supplied to the reactor was up to 215.1 kW.

Example 1

[0220] A particulate biosolids material containing 10 wt. % water and 60.6 wt. % volatiles were processed in the plasma reactor as described above. The particle size of the biosolids materials was 1-3 mm and its elemental composition in wt. % is shown in Table 1. The biosolids were fed to the reactor at a rate of 309.0 lb/hr (140.4 kg/hr), along with a nitrogen purge gas (working gas) at 3.0 lb/hr (1.4 kg/hr), a nitrogen torch gas (working gas) at 17.4 lb/hr (7.91 kg/hr), and an oxygen gas (reactive gas) at 68.0 lb/hr (30.9 kg/hr).

TABLE-US-00001 TABLE 1 Composition of Biosolids Feed Element Wt. % C 37.03 H 5.60 N 5.11 S 1.21 Ash 23.21 O 17.84 H.sub.2O 10

[0221] The output of the reactor comprised a syngas and a nanosized fraction of ash and carbon nanoparticles. The output flow of syngas was 314.7 lb/hr (143.0 kg/hr) and registered a temperature of about 1200 F. (649 C.). Composition of the recovered syngas is shown in Table 2. The H.sub.2 to CO ratio was 1.15:1, the proportion of N.sub.2 in other gaseous components different from H.sub.2, CO, CO.sub.2 and H.sub.2O was 83.8%.

[0222] The nanosized fraction of ash and carbon nanoparticles was produced at a rate of 82.7 lb/hr (37.6 kg/hr) and contained about 13.2 wt. % of carbon.

TABLE-US-00002 TABLE 2 Syngas Composition Component mole percent H.sub.2 47.4 CO 41.1 CO.sub.2 1.7 H.sub.2O 2.3 N.sub.2 6.2 Other gases 1.2

[0223] Based on the composition of this biosolids feed and the recovered syngas and ash, the carbon conversion was calculated at 90.4%.