Decontamination procedure using a biofilter to retain and recycle particulate matter from combustion fumes

Abstract

A fume decontamination system connected to any combustion system which comprises seven devices interconnected sequentially in the following manner: an extraction device is first connected to the combustion system and then connected by the other end to a guiding device which, in turn, is connected to a cooling device. Once cooled, the combustion gases are channeled to a suction device in which the gases are driven under pressure to an induction device which, in turn, concentrates the gases and directs same to the injection plenum, the concentrated, cooled gases being distributed at constant volumes to the entire biological plant filtering device and its decontamination procedure.

Claims

1. A fume decontamination procedure in connection with any combustion system of biomass and/or coal, CHARACTERIZED in that the fume decontamination procedure comprises the steps of: i) capturing smoke from the combustion system; ii) guiding the smoke at a constant speed through a regular section (5, 8 and 10); iii) cooling the smoke, wherein the smoke is distributed in a cooler (9) having lower sections, where the temperature is between 10° C. and 40° C. in the cooler and a flow of the smoke decelerates in each lower section relative to a flow of the smoke in the regular section; iv) injecting the cooled smoke into an injection box (16) thereby increasing a density of the smoke within the injection box relative to a density of the smoke in the cooler; v) transferring the smoke from the injection box (16) through ducts having a 1/10 cross section of the regular section (5, 8 and 10) and into a plenum (19), wherein transferring into the plenum increases the flow speed of the smoke by 140% relative to the flow speed of the smoke in the cooler (9); and vi) filtering particulate material from the smoke through a vertical wall of vegetation, wherein the smoke travels a contact surface with the vertical wall of vegetation, the vegetation capturing and absorbing the filtered particulate material.

2. The fume decontamination procedure according to claim 1, CHARACTERIZED in that the vertical wall of vegetation has a particle filtration performance of greater than 90% reduction in particulates.

3. The fume decontamination procedure according to claim 1, CHARACTERIZED in that injecting the cooled smoke includes regulating the flow of the smoke through an extractor (14) that receives flow orders from an electronic flow regulator device (15).

4. The fume decontamination procedure according to claim 1, CHARACTERIZED in that (iii) cooling the smoke includes reducing the temperature of the smoke from 250° C. to 10° C.

5. The fume decontamination procedure according to claim 1, CHARACTERIZED in that vi) filtering the smoke with the vertical wall of vegetation produces carbonic acid improving growth of the vertical wall of vegetation.

6. The fume decontamination procedure according to claim 1, CHARACTERIZED in that capturing smoke includes capturing smoke in a range of 216 to 512 m.sup.3/h and filtering particular material includes the vertical wall of vegetation having a volume in a range of 0.55 to 1.32 m.sup.3 and an efficiency over 90% of particulate material is removed.

7. The fume decontamination procedure according to claim 1 wherein vi) filtering includes passing the particulate material through a self-supporting vertical wall of vegetation.

8. The fume decontamination procedure according to claim 1 wherein vi) filtering includes passing the particulate material through the vertical wall of vegetation supported on a structure.

9. The fume decontamination procedure according to claim 1 wherein the lower sections consist of a series of ducts and during cooling, the smoke is separated into each duct of the series of ducts, and following separating and before injecting, the procedure further comprises combining the separated flows from each duct in the series of ducts into a single flow.

10. The fume decontamination procedure according to claim 9 wherein during cooling, a sum of the cross sectional areas of each duct in the series of ducts is greater than a cross sectional area of the regular section.

11. The fume decontamination procedure according to claim 9 wherein following separating and before combining, reducing the smoke travel speed in each duct in the series of ducts from the constant speed in the regular section.

12. The fume decontamination procedure according to claim 1 wherein the injection box has a volume that is one fourth a volume of the cooler and wherein injecting includes driving the cooled smoke into the injection box to increase the density of the cooled smoke.

Description

DESCRIPTION OF FIGURES

(1) FIG. 1/13

(2) This figure represents a sketch of the system of this invention composed of seven devices according to FIG. 1/13.

(3) A: extraction device

(4) B: Conveyance device

(5) C: Cooling device

(6) D: Suction device

(7) E. Induction device

(8) F: Injection plenum and

(9) G: Biological plant filtering device for the gases

(10) FIG. 2/13

(11) This figure presents a gas flow chart and its operation in the complete system. Also, the biofilter presented is one of the forms of execution of the vegetated wall structure without restricting it only to this.

(12) In general, this figure also presents the fundamental parts of the different devices that make up the system and some necessary parts, outside the system, for an understanding of the system as a whole: (1) Heater: refers to the original source of fume emissions, produced by the combustion of wood, pellets or the like. (2) Gas outlet duct: refers to the outlet duct for the heater (1) that conveys the fumes towards the exterior of the premises and in its final section will be intervened by the extraction joint (4) so as to generate an alternative fume conveyance path towards the plant biofilter. (3) Protection of the outlet duct: allows the correct exit of the fumes towards the exterior and protects the entire system (1 and 2) from the entry of water and other harmful elements.

(13) The system itself consists of the following elements: (4) Extraction connection: It is a T-shaped connector that creates a bifurcation to permit a flow of fumes, alternative to the original one. It consists of two intersected cylindrical ducts. The first duct maintains the continuity of the fume outlet duct (2), and must have the same diameter and be coupled correctly without seepages; the second duct conveys the fumes towards the plant biofilter. The extraction connection (4) can have a smoke sensor that activates the extractor (14) to start the system automatically. (5) Conveyance Element: consists of a cylinder that conveys the fumes towards the TEE (gas derivation element) register [6] (6) TEE register before the cooler (7) register cover before the cooler: The TEE register and the register cover, together, allow a change in direction of the conveyance of fumes in (5) and (8) and also the inspecting and cleaning of the section. (8) The conveyance element prior to the cooler: conveys the gases from the TEE register (6) towards the cooler (9). (9) The cooler: refers to a sealed element with only one input opening and another outlet for the gases. It consists of a connection to the conveyance element (8) and a derivation to a series of ducts having a rectangular section that separate and divide the flow of fumes with the purpose of reducing their temperature. In the final section of the element, regarding the direction in which the fumes advance, this group of ducts comes together again in a single rectangular-shaped chamber to become coupled, at a single point, to the conveyance element (10). (10) Conveyance element after the cooler: conveys the gases from the cooler (9) towards the TEE register (11). (11) The TEE register after the cooler: it consists of two intersected ducts. Combined with the register cover after the cooler (12), they permit a change of direction in the conveyance of fumes (10) towards the flange (13) and also inspect and clean the section. (12) Register cover after the cooler. (13) The flange is the element that joins the TEE register (11) with the extractor (14), allowing the dismantling of the latter without destructive operations, thanks to a circumference of perforations through which the stitch bolts are mounted. (14) The extractor is an electro-mechanical equipment that suctions the gases coming from the heater (1) to drive them towards the plant Biofilter (18). Its action is controlled by means of a flow regulating electronic device (15). The extractor (14) is connected directly to the drive box (16). (15) Electronic device that regulates flow. (16) The drive box: consists of a sealed box with only one entry opening and a gas exit, it receives fumes and conveys them to the injection plenum (19) by means of conveyance elements (17). (17) Conveyance elements: these are ducts that maintain the adequate pressure and flow for the entry of the fumes into the injection plenum (19), they are regulated manually by injection regulators (18). (18) Injection regulators: these regulators control the flow that enters the injection plenum. (19) The injection plenum: refers to a sealed chamber with an opening for the gas to enter and open on the side that connects with the plant Biofilter (20). The pressure of the gases that are introduced is spread equally throughout its internal surface and is integrated to the substrate in a constant manner. (20) Plant Biofilter: this is a green wall that acts as a biological filter like the one described in European patent PT1771062. This does not limit the existence of other spatial arrangements, for example, self-supported, without leaning against a wall where they could be applied as a biofilter. What is substantial is to maintain a certain verticality of the biofilter so that the fumes will travel over a greater area of it.

(14) FIG. 3/13

(15) This figure presents the component elements of the extraction device where the movement of the flow of gases can be seen very clearly.

(16) The numbers indicated in the figure are presented below: (2) gas outlet duct (3) protection of the outlet duct (4) extraction coupling (5) conveyance element

(17) FIG. 4/13

(18) This figure presents the component elements of the conveyance device where the movement of the flow of gases can be seen very clearly.

(19) The numbers indicated in the figure are presented below: (5) Conveyance element (6) TEE register before the cooler (7) register cover before the cooler (8) conveyance element before the cooler

(20) FIG. 5/13

(21) This figure presents the elements that are components of the cooling device where the movement of the flow of gases can be seen clearly.

(22) The numbers indicated in the figure are presented below: (8) The conveyance element prior to the cooler (9) The cooler 10) Conveyance element after the cooler.

(23) FIG. 6/13

(24) This figure presents the elements that are components of the suction device, clearly showing the movement of the flow of gases.

(25) The numbers indicated in the figure are presented below: (10) Conveyance element after the cooler. (11) The TEE register after the cooler. (12) Register cover after the cooler (13) The flange

(26) FIG. 7/13

(27) This figure presents other elements that are components of the suction device, clearly showing the movement of the flow of gases.

(28) The numbers indicated in the figure are presented below: (13) The flange (14) The extractor (15) Electronic device that regulates the flow.

(29) FIG. 8/13

(30) This figure presents the elements that are components of the induction device where the movement of the flow of gases can be seen clearly.

(31) The numbers indicated in the figure are presented below: (16) The drive box (17) Conveyance elements (18) Injection regulators

(32) FIG. 9/13

(33) The figure on the upper left presents the component elements of the injection plenum, clearly showing the movement of the flow of gases.

(34) The figure on the upper right presents the configuration of the biofilter supported on a structure that already exists; therefore, the plenum also presents a lower injection configuration, where the gases are distributed in the biofilter through the plenum's inner channels.

(35) The inferior figure shows the second configuration of the plenum when the biofilter is sustained on an existing structure, where the position of the plenum is lateral and distributes the gases through a fabric especially suitable for these purposes.

(36) The numbers indicated in the figure are presented below: (19) The injection plenum (21) Inner channels of the plenum (22) Gas distribution fabric

(37) FIG. 10/13

(38) This figure presents the component elements of the plant biological filtering device in a configuration sustained on an existing wall or support, clearly showing the movement of the flow of gases.

(39) The number indicated in the figure is presented below: (20) Plant biofilter

(40) FIG. 11/13

(41) This figure presents, on the left, the component elements of the injection plenum, when the configuration of the plant biological filter is selfsustained with an inferior plenum, where the movement of the flow of gases can be seen very clearly.

(42) On the other hand, the figure on the right presents the configuration of the plant biological filter when it is selfsustained showing the tubes that distribute the gas internally and that are part of the inferior plenum.

(43) The number indicated in the figure is presented below: (19) injection plenum (21) Inner channels of the plenum

(44) FIG. 12/13

(45) This figure presents the component elements of the plant biological filtering device, in a self-sustained configuration in the same structure of the biological filter, where the moment of the flow of gases can be seen clearly.

(46) The number indicated in the figure is presented below: (20) Plant biofilter

(47) FIG. 13/13

(48) This figure presents two schematic drawings, the upper drawing presents the decontamination system operating for three months and the growth of the plants associated to the biofilter.

(49) The lower drawing presents the biofilter alone, filtering environmental air, not connected to the decontamination system.

EXAMPLES OF APPLICATION

(50) To prove the efficiency of the device, five pilot plants with similar characteristics and different measurements were installed. One of these pilot plants was taken as a reference, according to the following characteristics: the device was connected using an extraction coupling (4) at the gas outlet (2) from a double combustion Heater (1) of 8.8 kW, the measurement in kW refers to the original source of fume emissions, a product of biomass combustion among others.

(51) Wood with a humidity equal to or of less than 17% was used for executing the tests, although this invention is not limited with regard to the humidity of the fuel.

(52) The total journey of the fumes via the ducts is 14 m.

(53) The system employed consists of: An extraction coupling (4) that branches the fumes, installed at 6.00 m between the end of the gas outlet duct (2) and the outlet duct protection element (3). It is conveyed above the 6 meters of duct (5) from the T coupling or bifurcation to the T register of section (6) and from this element by conveyance (8) five meters to the entry of the cooler (9), of 3 m.sup.2 of dissipation surface and three routes. The suction of the cooler's fumes (9) was executed by a medium pressure and simple aspiration centrifugal fan with housing and turbine with maximum flow of 1691 m.sup.3/h (14) and compressed in the drive box (15) of 0.04 m.sup.3 volume. The flow of the regime registered during the tests was 311 m.sup.3/h. From the drive box (15), the fumes were injected into the 0.8 m.sup.3 plenum, whose function is to distribute homogeneously the entry of the fumes into the biofilter, in this case a 4 m.sup.2 and 20 cm thick green wall. Acidification of the substrate of the biofilter helping the liberation of nutrients towards the plants of the biofilter. Improvements in the growth of the biofilter's plants maintaining the same amount of irrigation water.

(54) The System's Data are Summarized in the Following Table I:

(55) TABLE-US-00001 TABLE I System MFB 01 Type E20 Location: Nahuelbuta Street 2047, Temuco Dimension: Biofilter 2.00 × 2.00 0.20 m Volume: Biofilter 0.8 m.sup.3 Extraction length: 14.00 m Diameter of ducts: Galvanized Ø 15.24 cm Radiator: Galvanized 3.2 m.sup.2 area of dissipation Heater model: without brand, double chamber type. Slow combustion. Extractor model: Medium pressure and simple aspiration centrifugal fan with housing and turbine. Maximum flow: 1691 m.sup.3/h Flow regime: 311 m.sup.3/h Sampling speed: 1.2 m/s Injection to plenum: Independent, one per c/m.sup.2 Total volume plenum: 0.8 m.sup.3 Screen: Stainless steel mesh 300 micras Biofilter: inert plant fiber Fuel: Wood % Humidity: 17%

(56) The experimental results observed during this test, according to the CH5 method (method used under Chilean rules to make measurements in fixed sources of gases) for determining the emissions of particles from stationary sources, were the following:

(57) TABLE-US-00002 RESULTS OF THE MEASUREMENT Biofilter No 1 Prior to the biofilter PARAMETER C3 C4 C average D DATE 13 Jul. 2015 13 Jul. 2015 TIME 13:40 15:00 14:53 16:14 Conc. of Particulate 652.40 432.48 542.44 155.51 Matter (mg/m.sup.3N) Corrected Conc. 652.40 432.48 542.44 155.51 Particulate Matter (mg/m.sup.3N) Hourly issuance 0.20 0.14 0.17 0.05 Standardized gas flow 314 314 314 0 (m.sup.3N/h) Excess of air (%) % O.sub.2 19.0 17.8 18.4 0.9 % CO.sub.2 1.7 1.7 1.7 0.0 ppm CO 3379.0 6000.0 4689.5 1853.3 Isokinetism (%) 96.9 97.8 97.4 0.6 Humidity of 1.2 1.3 1.3 0.1 the gases (%) Speed of the 1.19 1.19 1.19 0.00 gases (m/s) Temperature of the 9.3 9.6 9.5 0.2 bases (° C.) PARAMETER C1 C2 C average D DATE 13 Jul. 2015 13 Jul. 2015 TIME 10:40 12:05 11.54 13:19 Conc. of Particulate 53.95 16.94 35.44 26.18 Matter (mg/m.sup.3N) Corrected Conc. 53.95 16.94 35.44 26.18 Particulate Matter (mg/m.sup.3N) Hourly issuance 0.02 0.01 0.01 0.01 Standardized gas flow 314 313 313 1 (m.sup.3N/h) Excess of air (%) % O.sub.2 20.0 19.0 19.5 0.7 % CO.sub.2 0.0 1.7 0.9 1.2 ppm CO 6000.0 4000.0 5000.0 1414.2 Isokinetism (%) 99.6 96.9 98.3 1.9 Humidity of 1.3 1.1 1.2 0.1 the gases (%) Speed of the 1.20 1.20 1.20 0.00 gases (m/s) Temperature of the 10.9 11.8 11.3 0.6 bases (° C.) Performance Biofilter No 1 = 93.47% Date: 13 Jul. 2015 Address: Nahuelbuta 2047 (*) Final results

(58) The results of these tests clearly indicate a performance greater than 90%, preferably 93.47%, where the reduction of different emissions was achieved and especially the particulate material.

(59) In general, the results of five of the experiments gave a range of efficiency in particulate material retention of between 72 to 95%.

(60) The flow of filtered fumes operative in the different tests goes from 300 m.sup.3/h to 500 m.sup.3/h; these flow values do not restrict the current development.

(61) An interesting result is the relationship that each 390 m.sup.3/h flow in regime of smoke requires 1 m.sup.3 of biofilter and was confirmed for the range between 216 to 512 m.sup.3/h of flow in regime of smoke with an equivalent range of biofilter volume between 0.55 to 1.32 m.sup.3 to achieve a filtering with an efficiency above 90%. These values are not restrictive to other flows in which the system could be applied.

(62) A second experiment demonstrated the efficiency in the growth of the biofilter depending on the injection of the fumes from the combustion devices (FIG. 13/13).

(63) The smoke coming out of the chimney had a flow of 390 m.sup.3/h. On the other hand, the experiment was carried out for three winter months.

(64) In this experiment, a biofilter was used, mounted on a wall with a volume of the same m.sup.3, with a lateral injection plenum.

(65) One of the phenomenon detected in this test was the rapid acidification of the soil by the generation of carbonic acid when the carbon monoxide of the products derived from the combustion came into contact with the irrigation water. This phenomenon causes the roots to be more exposed to the absorption of nutrients necessary for their growth.