Flue gas emissions reduction technology

Abstract

The disclosure provides a method of treating flue gas that has one or more components. The method comprises passing a solution through both a magnetic field and an electric field to form an activated solution. The method also comprises contacting the activated solution with the flue gas so that the one or more components of the flue gas are at least partially absorbed by the activated solution to form a residue solution.

Claims

1. A system for treating flue gas that has one or more components, comprising: a conduit having an inner passage that is configured to deliver a solution to flue gas; an electric field generator a first antenna or dipole and a second antenna or dipole for generating the electric field therebetween, the first antenna or dipole and the second antenna or dipole being positioned on an outside surface of the conduit so as to not directly contact the solution passing through the inside of the conduit; a magnetic field generator comprising a magnetic field coil that is positioned on the outside of the conduit and positioned between the first antenna or dipole and the second antenna or dipole so as to not directly contact the solution passing through the inside of the conduit, the magnetic field generator configured to generate a magnetic field; wherein the system is configured so that the solution that is passed through the conduit and is delivered to the flue gas is activated by the electric field and magnetic field to form an activated solution, the activated solution being passable through an opening of the conduit to contact the flue gas to at least partially absorb one or more of the components of the flue gas to form a residue solution.

2. A system as claimed in claim 1, wherein the magnetic field generator is a magnetic coil that is configured to generate a magnetic flux density of between 0.01 μT to 1 mT.

3. A system as claimed in claim 1, wherein the electric field generator is configured to generate an oscillating sinusoidal waveform between the first antenna or dipole and the second antenna or dipole.

4. A system as claimed in claim 3, wherein a frequency of the oscillating electric field ranges from 0.3 Hz to 100 MHz.

5. A system as claimed in claim 1, wherein the opening is an apparatus for generating a vapour and/or mist of activated solution in the flue gas.

6. A system as claimed in claim 1, wherein the system further comprises a collection port for collecting the residue solution.

7. A system as claimed in claim 1, wherein the system is configured to continuously treat flue gas.

8. A system as claimed in claim 1, further comprising a pump for pumping the activated solution through the conduit.

9. A system as claimed in claim 1, wherein the electric field generator and magnetic field generator are positioned on an upstream side of a boiler and the opening of the conduit is positioned on a downstream side of the boiler.

10. A flue fitted with the system of claim 1.

Description

BRIEF DESCRIPTION OF FIGURES

(1) FIG. 1 shows an embodiment of a system for treating flue gas.

(2) FIG. 2 shows another embodiment of a system for treating flue gas.

(3) FIG. 3 shows an embodiment of a device used for treating flue gas.

DETAILED DESCRIPTION

(4) An embodiment of a system 10 for treating a flue gas is shown in FIG. 1. A solution, in the form of water 11, is held in reservoir 12 and is in fluid communication with conduit 14. A pump 16 is connected to conduit 14 to pump water from the reservoir 12 through a magnetic field generator 18 and an electric field generator 20. The magnetic field generator 18 and electric field generator 20 are positioned around an exterior surface of the conduit 14 so that they are coaxially arranged with the conduit 14. The conduit 14 passes first through magnetic field generator 18 and then the electric field generator 20, but in other embodiments this order is reversed, or alternatively, the magnetic field generator 18 and an electric field generator 20 are provided in the same device. In one embodiment, the magnetic field generator 18 is positioned between first and second antenna of the electric field generator 20. In some embodiments, more than two antennas are used. Alternatively, some embodiments use one or more antennae. The magnetic field generator 20 is a magnetic coil that is configured to generate a magnetic flux density of between 0.0002 μT to 10 T. The electric field generator is configured to generate an oscillating frequency from about 0.3 Hz to 2,000 kTHz. Further, in the embodiment of FIG. 1, the electric field generator is configured to generate an oscillating sinusoidal waveform generated at a first antenna or dipole and a second antenna or dipole, where the sinusoidal waveform generated at the first antenna is 180° out of phase with the sinusoidal waveform generated at the second antenna.

(5) In some embodiments, the magnetic field generator 18 is not required as the system 10 can rely on background magnetic fields, such as the earth's magnetic field. The water can be salt water, or at least be saltier than drinking water. In some embodiments, potable e.g. tap water is used in system 10.

(6) The conduit 14 extends from electric field generator 20 into secondary conduit 22. A plurality of openings in the form of misting nozzles 26 are in fluid communication with the secondary conduit 22. The misting nozzles 26 pass through a wall of a flue 24 so that they are in contact with an internal volume 25 of the flue 24. In use of the system 10, water is passed, through activation of the pump 16, through the magnetic field generator 18 and an electric field generator 20 to activate the water. This activated water is then delivered into the internal volume 25 as a fine mist so that it can contact flue gas, as represented by arrow 28, passing through the internal volume. The specific arrangement of the flue 24, misting nozzles 26, conduit 14 and secondary conduit 22 in FIG. 1 is exemplary only and can take on many other forms. For example, in some embodiments misting nozzles 26 are attached to conduit 14 and secondary conduit 22 is not used. In other embodiments, there are more or less than four misting nozzles. In other embodiments, the misting nozzles are provided as separate groups to treat separate sections of the flue 24. In other embodiments, more than one system 10 is fitted to the flue 24 to treat flue gas 28. The flue gas 28 can be under pressure to drive it through the flue or a fan or pump can be used to drive the flow of the flue gas 28.

(7) Once the fine mist of activated water contacts the flue gas 28, components of the flue gas such as particulate carbon, CO.sub.2, CO, NO, NO.sub.x, and SO.sub.x are absorbed by the activated mist to form residue mist which then condenses into residue water. In use of the system 10, a volume of activated mist will be delivered to the internal volume 25, with the total volume being dependent on the dose rate of activated water and the type of flue gas to be treated (e.g. the expected amount(s) of contaminates to be treated by the activated mist). To prevent flooding of the flue 24, a tap 30 is provided to drain the residue water. The tap 30 in some embodiments is provided as a sump to allow residue water to collect but prevent flue gas 28 from escaping the flue 24. Although not shown in FIG. 1, the residue water is then removed and components in the residue solution, such as particulate carbon, are then able to be extracted and treated and/or reused.

(8) In some embodiments the water 11 is delivered via gravity, which may eliminate the requirement for pump 16. Instead, a valve of similar can be used to control a flow rate of the water through conduit 14. The water 11 can be continuously pumped through the magnetic field generator 18 and electric field generator 20 to treat the flue gas 28, or a pulsed pumping method may be used.

(9) In an embodiment (not shown), the activated water can be passed through a boiler associated with a power station after the magnetic field generator 18 (if provided) and electric field generator 20. The secondary conduit 22 or similar is positioned downstream of the boiler and the flue 24 is associated with the boiler.

(10) In an embodiment, a device 200 is used to provide the magnetic field and electric field, as shown in FIG. 3. A waveform supplied to the magnetic field (EM) generator 206 of the device 200 is generated by a wave duplicator and phase generator 204, which also supplies the waveform to the electric field generator 208 (FIG. 3). The input to the wave duplicator and phase generator 204 is supplied by a wave generator with tunable frequency output module 202. The arrangement of the device 200 helps to ensure that the frequency of the magnetic field coil waveform is the same as the frequency of the antennae waveform. This arrangement can also help to ensure that the phase of the magnetic field coil is the same as that of one of the antennae. In the embodiment of FIG. 3, the magnetic coils associated with the magnetic field generator are positioned between the antennae of the electric field generator.

(11) FIG. 2 shows another embodiment of a system 100 for treating flue gas. In system 100, the flue gas is configured to travel through flue 112. Flue 112 has a smoke inlet 114 that allows ingress of flue gas into flue 112. In use, the smoke inlet 114 would be connected to an exhaust outlet for a combustion chamber. The combustion chamber is used to combust a combustible fuel. Therefore, exhaust from the combustion chamber is funneled out of the outlet and into smoke inlet 114. The term combustion chamber is used broadly to include combustion chambers from power stations, refineries, industrial power and heat generation systems, shipping and waste incinerators, cement factories, lime factories, kilns, commercial and pleasure craft.

(12) Flue 112 has an extraction fan 116 to assist in pumping flue gas through flue 112. Extraction fan 116 is not required in all embodiments to pump flue gas through flue 112. The flue 112 also has a collection port in the form of sump 118 to act as residual capture points for collecting residue solution. The general U-shape of flue 112 allows residue solution to pool in the sump 118 without restricting flow of the flue gas through flue 112.

(13) The flue 112 has a primary washing chamber 112a and a secondary washing chamber 112b. However, there can be any number of washing chambers, and the total number of washing chambers will be dependent on the amount and type of flue gas to be treated.

(14) A viewing window 124 is positioned upstream of fan 116 to allow visual inspection of the treated flue gas and to allow for sensors (not shown) to monitor the composition of the flue gas in the presence of the activated mist. In some embodiments, the sensors are in communication with a pump used to pump water through pipe 120. For example, if the sensor detects that the level(s) of components in the flue gas post-treatment are above a threshold value, the pump can be instructed via programmable computer logic (PLC) to increase the pumping rate to increase the rate of activated vapour and/or mist formation to increase the rate of absorption of flue gas components.

(15) A conduit in the form of pipe 120 is positioned around flue 112. One end of pipe 120 is in communication with a reservoir that can hold a volume of solution such as water (not shown). Pipe 120 has openings in the form of misting nozzles 122. In the embodiment of FIG. 2, the system has four misting nozzles placed along a length of flue 112, but other embodiment have more or less than four misting nozzles. The number of misting nozzles depends on the size of the flue 112 and the amount of flue gas to be treated. Water traveling through pipe 120 exits the misting nozzles to form a mist of water in the flue 112, where the mist of water contacts any flue gas that is traveling through flue 112. In some embodiments, the openings are in the form that provides a vapour in addition to or in place of mist.

(16) Prior to forming a mist of water, the water is passed through an electric field and a magnetic field to form an activated solution (not shown). In this way, the mist generated from the activated water can be considered an activated mist. The electric field is generated from an electric field generator and the magnetic field is generated from a magnetic field generator (not shown), or in some embodiments is provided as the earth's magnetic field. In the embodiment of FIG. 2, the solution is activated using an electric field and magnetic field as described in US2014/0374236. In some embodiments the water is activated as it is passed through pipe 112 prior to exiting misting nozzles 122. This allows water to be continually activated as needed. However, in some embodiments the water is activated in bulk, stored in the reservoir, and then pumped through pipe 120. In these embodiments, the water can be activated e.g. off-site and transported to the reservoir, or the water can be activated once in the reservoir.

(17) The activated mist contacts the flue gas in use, which allows components of the flue gas such as particulate carbon, CO.sub.2, CO, NO, NO.sub.x, and SO.sub.x to be absorbed by the activated mist to form residue mist. The droplets of residue mist are then able to pool into sump 118 to form a residue solution. The residue solution is then removed and components in the residue solution, such as particulate carbon, are then able to be extracted and reused.

Examples

(18) System

(19) A stainless steel drum having a 525 cm diameter×460 cm height was fitted with a brazier and an air blower to aid combustion. A length of 125 mm flexible aluminium ducting was used to direct the flue gas from the combustion into the flue.

(20) The flue similar to that described in FIG. 2 comprised one 100 mm×1000 mm chamber fitted with three misting sprays and one 100 mm×850 mm wash chamber fitted with a single misting spray. A U-bend configuration residual capture unit was configured below each washing chamber. This had the dual purpose of sealing the washing chamber from the atmosphere and providing a point from where a sample of used fluid could be drawn for analysis. The downstream end of the U-bend was vented to the atmosphere at a level that retained the seal to the washing chamber at a constant level while allowing overflow residual fluid to be collected for further analysis if necessary. This configuration automatically prevented the washing chamber from becoming flooded irrespective of the volume of fluid delivered by the spray nozzles.

(21) The sampling chamber was a 100 mm×1300 mm tube fitted with a clear observation window and a sampling port 1150 mm from the fourth spray nozzle. The clear window was necessary to monitor and avoid fouling of a Unigas 3000+ probe and the position of the sample port satisfied the requirements for a thoroughly mixed sample while reducing the likelihood of the analyser probe becoming contaminated.

(22) A 12 volt electrical circuit was designed to provide power to a 200 psi pump, 100 watt air blower and a rheostat controlled extraction fan which was fitted at the exhaust end of the apparatus to ensure positive flow through the system.

(23) Tap water was treated with an electric field and magnetic field as described in US2014/0374236.

(24) A new calibrated Unigas 3000+ Flue Gas Analyser configured to measure O.sub.2, CO.sub.2, CO, SO.sub.2, NO and NO.sub.x was utilised for gas analysis.

(25) Black Coal

(26) 1 kg of crushed black coal was ignited in the stainless steel burner and, with the assistance of a blown air source, was taken to over 385° C. whereupon the smoke effluent became relatively clear. This output was ducted through the flue and analysed using the Unigas 3000+ Flue Gas Analyser immediately prior to activating the spraying of the activated water. This reading was labelled the “Control Coal Smoke” sample.

(27) The activated water was then pumped to the first wash chamber subjecting the burner output (smoke effluent) to the micro mist produced by three of the misting nozzles. The used residual fluid was collected in the first residual capture unit for further analysis. The washed smoke effluent flowed into the second wash chamber where it was subjected to the micro mist from the fourth spray nozzle. The residual from this chamber was collected in the second residual capture unit for possible further analysis.

(28) The smoke effluent then entered the sampling chamber and was analysed via the Unigas 3000+ probe at the same port. This reading was labelled “Treated Coal Smoke” sample. The processed smoke effluent was finally released into the atmosphere through the extraction fan.

(29) Gas sampling and analysis was conducted using the Unigas 3000+ Flue Gas Analyser. The data sought was a comparison between treated and raw (control) samples. To ensure that the sample smoke effluent properties remained uniform, a short time span between taking the samples was a prime requirement. The ability of the Unigas 3000+ to self-calibrate and continually analyse allowed the samples to be acquired within minutes of each other.

(30) Consequently the data proved to be sufficiently accurate to provide reliable results for the gases targeted by these experiments.

(31) Although the smoke effluent output from the burner appeared to be relatively clear (Ringleman Standard 1 to 2), the residual sample taken from the first (three spray) wash chamber was unexpectedly dark in comparison with the source water. This indicates that the activated water is actually removing carbon (and particulates) from the effluent. The residual sample from the second wash chamber was also dark, even though the temperature of the second wash chamber was considerably lower (approaching ambient) than the smoke effluent gases in the first chamber. This indicates that although the spray cools the smoke effluent, the effect of the activated treatment is not temperature dependent.

(32) An experiment was also completed to identify the effects of using unactivated (i.e. regular tap) water on the flue gas from Black coal. The unactivated water cooled the flue gases similarly to the activated water and also captured some particulates, but there was no significant percentage change to the composition of the gases in the effluent.

(33) These results indicate that the presence of a magnetic and electric field helps to solubilise aggregate, particulate, mineralogical and ionic matter that can react with the flue gas. For example, the solubility of calcite may increase which would increases the Ca.sup.2+ and CO.sub.3.sup.2− concentration in solution. Increases in CO.sub.3.sup.2− helps in solubilising CO.sub.2 in solution due to the higher pH and greater ability to form species such as H.sub.2CO.sub.3, which can dissociate to form bicarbonate which can then form precipitates such as calcium bicarbonates. This effectively shifts the partitioning coefficient of CO.sub.2 between the gas phase and aqueous phase towards the aqueous phase. Although calcium is used as an example, many other mineralogical species, such as those found in scale in aqueous plumbing, can be solubilised and react with flue gas such as CO.sub.2.

(34) The activated water may also help to shift the partitioning coefficient for other gases such as NO, NO.sub.x and SO.sub.2 towards the aqueous phase for similar reasons presented above.

(35) The increase in the percentage of O.sub.2 can be explained by the outgassing of O.sub.2 dissolved in the activated water. Further, removal of CO.sub.2 from the flue gas to form treated flue gas changes the composition of the treated flue gas, and this may change the partial pressures of each gas that makes up the treated flue gas. If the partial pressure of oxygen increases, then this would promote outgassing of O.sub.2 dissolved in the activated water. Further, the high surface area of the activated mist and/or vapour in the flue helps to increase the amount of oxygen that is able to outgas from the activated mist and/or vapour. However, in some embodiments, the observed increase in O.sub.2 is a result of removal of gases such as CO.sub.2 and CO from the flue gas, which mean the same amount of O.sub.2 now occupies a greater proportion of the resulting treated flue gas.

(36) It should be appreciated that the specific mechanism by which the CO.sub.2 and other gases are removed from the flue gas when treated by the activated water may vary depending on the specific composition of the flue gas and what solutes are present in the activated water.

(37) TABLE-US-00001 TABLE 1 results from black coal Gas Control With activated Percentage Measured Smoke water Change O.sub.2 20.7% 21.1%   +1.93% CO.sub.2 0.30% 0.00% −100.00% CO 0.20% 0.00% −100.00% NO(ppm) 13 6  −53.85% NO.sub.x(ppm) 13 6  −53.85% SO.sub.2(ppm) 10 0 −100.00%

(38) Diesel Fuel

(39) Considerable difficulty was expected in obtaining control smoke data due to the high particulate content of diesel smoke rapidly obstructing the Unigas 3000+ filter. In the event, the filter, although very dirty, did not choke completely and meaningful results were obtained.

(40) Nevertheless, these results are not considered definitive and improvements on the % change figures are anticipated with superior measuring equipment.

(41) TABLE-US-00002 TABLE 2 results from Diesel Fuel Gas Control With activated Percentage Measured Smoke water Change O.sub.2 17.9% 20.7%  +15.64% CO.sub.2 2.20% 0.20%  −90.91% CO 0.08% 0.00% −100.00% NO(ppm)  4  0 −100.00% NO.sub.x(ppm)  5  0 −100.00% SO.sub.2(ppm) 70 11  −84.29%

(42) Brown Coal

(43) The experiment with Brown coal followed the same process as the Black coal, but the smoke output was not as transparent. This may have to do with the higher water content of the fuel, so some of the perceived smoke may have actually been steam.

(44) TABLE-US-00003 TABLE 3 results from Brown Coal Gas Control With activated Percentage Measured Smoke water Change O.sub.2 17.50% 20.7%  +18.29% CO.sub.2  2.50% 0.20%  −88.00% CO  0.08% 0.00% −100.00% NO(ppm) 16 3  −81.25% NO.sub.x(ppm) 19 4  −78.95% SO.sub.2(ppm) 16 8  −50.00%

(45) Bunker Oil

(46) The Bunker oil would not ignite at the ambient temperature, so it had to be heated using traditional paraffin fire-lighters before it could be ignited. This is consistent with reports from shipping (where this is a major fuel source) where they have to keep this fuel above 130 Degrees C. for it to become combustible.

(47) Once this was done, it burned very well but with a very dark (high soot/particulate) smoke output, which resulted in fouling the Unigas 3000+ filters soon after meaningful readings were obtained. Subsequent readings were considered suspect due to the evident fouling.

(48) TABLE-US-00004 TABLE 4 results from Bunker oil Gas Control With activated Percentage Measured Smoke water Change O.sub.2 17.50% 20.7% +18.29% CO.sub.2  2.50% 0.30% −88.00% CO  0.08% 0.01% −87.50% NO(ppm)  31 14 −54.84% NO.sub.x(ppm)  32 14 −56.25% SO.sub.2(ppm) 351 60 −82.91%

(49) In the claims which follow and in the preceding description, except where the context requires otherwise due to express language or necessary implication, the word “comprise” or variations such as “comprises” or “comprising” is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the method and system.