WO2005023415A1

WO2005023415A1 - Dual-step process of industrial enterprise stack gas decontamination containing electron beam irradiation and treatment by gas discharge

Info

Publication number: WO2005023415A1
Application number: PCT/US2004/029057
Authority: WO
Inventors: Gennadiy Ivanovitch Klenov; Vladimir Petrovich Larionov; Aziz Khasaevich Kadymov; Gary F. Bowser
Original assignee: ScanTech Holdings LLC
Current assignee: ScanTech Holdings LLC
Priority date: 2003-09-04
Filing date: 2004-09-03
Publication date: 2005-03-17
Anticipated expiration: 2006-03-04

Abstract

A system for removing sulfur dioxide (S02) and nitrogen oxides (NOx) from the gases of a gas stream using irradiation of the gases with a particle accelerator in combination with gas discharge. The system treats the gases in a first stage using gas discharge lighted by a first electron beam from a first particle accelerator and in a second stage with a second electron beam from a second particle accelerator. By so lighting the gases between energized electrodes and preliminarily ionizing the gases, a stable, uniform gas discharge is maintained in an ammonia-rich environment at near atmospheric pressure during the first stage, thereby enabling a significant reduction in the amount of sulfur dioxide (S02) present in the gases. By significantly reducing the amount of sulfur dioxide (S02) in the first stage, the energy required to remove a substantial amount of nitrogen oxides (NOx) during the second stage is reduced substantially.

Description

DUAL-STEP PROCESS OF INDUSTRIAL ENTERPRISE STACK GAS DECONTAMINATION CONTAINING ELECTRON BEAM IRRADIATION AND TREATMENT BY GAS DISCHARGE

CROSS-REFERENCE TO RELATED APPLICATION [0001] This application claims the benefit of priority to United States Provisional Patent Application Serial Number 60/500,178, which is entitled "DUAL-STEP PROCESS OF INDUSTRIAL ENTERPRISE STACK GAS DECONTAMINATION CONTAINING ELECTRON BEAM IRRADIATION AND TREATMENT BY GAS DISCHARGE" and was filed on September 4, 2003.

FIELD OF THE INVENTION [0002] The present invention relates, generally, to the field of apparatuses and methods for reducing emissions in stack gases and, more particularly, to the field of apparatuses and methods using charged particle accelerators and gas discharge to reduce the amount of sulfur dioxide (S0₂) and nitrogen oxides (NO_x) in stack gases released from industrial facilities.

BACKGROUND OF THE INVENTION [0003] Over the years, a number of stack gas decontamination systems have been designed, developed, and/or constructed to treat stack gases produced by processes generally found at industrial enterprises or facilities. The processes often include combustion processes in which coal, oil, or natural gas is burned with by-product gases such as, but not limited to, sulfur dioxide (S0₂) and nitrogen oxides (NO_x) being created and directed into the atmosphere as stack gases through conduits referred to as "stacks" or "flues". Because the by-product gases travel through the stacks or flues, they are referred to, typically, as "stack gases" or "flue gases". Such stack gas decontamination systems attempt to reduce the consequential pollution caused by the release of stack gases into the atmosphere by processing, treating, or "decontaminating", the stack gases through the removal of harmful pollutants such as sulfur dioxide (S0₂) and nitrogen oxides (NO_x) therefrom. [0004] In one such stack gas decontamination system, ammonia (NH₃) and water vapor (H₂0) are added to stack gas to lower the temperature of the gas and to create a suitable environment for chemical reactions to occur. The gas is then irradiated with high-power electron accelerators to initiate and maintain the chemical reactions that convert sulfur dioxide (S0₂) and nitrogen oxides (NOχ) into powder sulfate and ammonium nitrate, which are commonly used as fertilizers. While this system can remove as much as 80 - 90% of the sulfur dioxide (SO₂) and nitrogen oxides (NO_x) present in the stack gases, the energy required to power the high-power electron accelerators is, unfortunately, very high. For example, if this system were to be employed to decontaminate the stack gases of a power plant, approximately 5 - 10% of the power produced by the power plant would be required to power the system's high-power electron accelerators.

[0005] In another similar stack gas decontamination system, a stationary corona discharge is employed to initiate and maintain the chemical reactions in lieu of the high-power electron accelerators. In tests of this system, the stationary corona discharge - consumed only 60 - 90 watts of power and the system removed 90 - 95% of the sulfur dioxide (S0₂) and 5 - 20 % of the nitrogen oxides (NO_x) from stack gas having a flow rate of 1 ,200 cubic meters per hour. Unfortunately, only the sulfur dioxide (S0₂) was substantially removed from the stack gases.

[0006] There is, therefore, a need in the industry for a system for removing substantial amounts of sulfur dioxide (S0₂) and nitrogen oxides (NO_x) from a gas stream with minimal energy consumption that solves the above-described and other related, and unrelated, shortcomings of prior technology.

SUMMARY OF THE INVENTION [0007] Broadly described, the present invention comprises a system, including apparatuses and methods, for removing sulfur dioxide (S0₂) and nitrogen oxides (NO_x) from the gases of a gas stream using irradiation of the gases with a particle accelerator in combination with gas discharge. More particularly, the present invention comprises a system, including apparatuses and methods, for removing sulfur dioxide (S0 ) and nitrogen oxides (NO_x) from the gases of a gas stream by treating the gases in a first stage with gas discharge lighted by a first electron beam and in a second stage with a second electron beam.

[0008] In an exemplary embodiment, the present invention is embodied in a stack gas decontamination system including a first chamber in which gases of a gas stream to be treated are mixed with ammonia and water vapor to produce a moist, ammonia-laden environment for subsequent treatment of the gases. The stack gas decontamination system also includes a second chamber having a plurality of electrodes therein that receives the moist, ammonia-laden gases from the first chamber. Concurrently, during a first stage of processing or treatment of the gases at near atmospheric pressure and in the ammonia-laden environment, high-voltage power is applied to the electrodes and an electron beam of accelerated electrons from a first particle accelerator is directed into the gas between the electrodes. The energy of the accelerated electrons lights the gas between the electrodes, providing preliminary ionization of the gas and producing a stable, uniform gas discharge in conjunction with the high-voltage power applied to the electrodes. The gas discharge causes the removal of a majority of the sulfur dioxide (S0₂) and a minority of the nitrogen oxides (NO_x) from the gases as they flow through the second chamber. The stack gas decontamination system additionally includes a third chamber in which the moist, ammonia-laden gases are further processed or treated during a second stage of processing that includes irradiation of the gases by a beam of accelerated electrons produced by a second particle accelerator to significantly remove nitrogen oxides (NO_x). The gases exit the stack gas decontamination system with substantial reductions in the amounts, or concentrations, of the sulfur dioxide (S0₂) and nitrogen oxides (NOx) therein.

[0009] Advantageously, the dual-stage system and methods of the present invention significantly reduce the amounts, or concentrations, of sulfur dioxide (S0₂) and nitrogen oxides (NO_x) in the gases of a gas stream such that after processing, the gas stream includes 2-8% of the sulfur dioxide (S0₂) and 15-35% of the nitrogen oxides (NO_x) present in the gas stream prior to processing. By lighting the gases of the gas stream present between electrodes with an electron beam of a particle accelerator directed therebetween during a first stage of processing, a stable, uniform gas discharge is maintainable in a large chamber (e.g., having a volume of several cubic meters to several tens of cubic meters) having an ammonia-rich environment at near atmospheric pressure, thereby enabling the treatment of a substantially larger volume of gas than with other methods and causing a significant reduction in the amount of sulfur dioxide (S0₂) present in the gas. Because a substantial reduction in the amount of sulfur dioxide (S0₂) occurs during the first stage of processing, the amount of energy required to remove a significant amount of nitrogen oxides (NO_x) is significantly reduced as compared to the amount of energy that would, otherwise, be required to remove a comparable amount of nitrogen oxides (NO_x) without such first stage processing having been performed previously.

[0010] Other objects, features, and advantages of the stack gas decontamination system will become apparent upon reading and understanding the present specification when taken in conjunction with the appended drawings.

BRIEF DESCRIPTION OF THE DRAWINGS [0011] Fig. 1 displays a block diagram representation of a stack gas decontamination system for removing sulfur dioxide (S0₂) and nitrogen oxides (NO_x) from a stack gas stream of an industrial facility in accordance with an exemplary embodiment of the present invention.

[0012] Fig. 2 displays a front, elevational, schematic view of a second chamber of the stack gas decontamination system of Fig. 1. [0013] Fig. 3 displays a side, elevational, schematic view of a second chamber of the stack gas decontamination system of Fig. 1 , illustrating a first configuration of a plurality of electrodes therein. [0014] Fig. 4 displays a side, elevational, schematic view of a second chamber of the stack gas decontamination system of Fig.1, illustrating a second configuration of a plurality of electrodes therein.

DETAILED DESCRIPTION OF THE INVENTION [0015] Referring now to the drawings in which like numerals represent like elements or steps throughout the several views, Fig. 1 displays a block diagram representation of a stack gas decontamination system 100 for removing sulfur dioxide (SO₂) and nitrogen oxides (NO_x) from a stack gas stream of an industrial enterprise, or facility, in accordance with an exemplary embodiment of the present invention. The stack gas decontamination system 100 comprises a first chamber 102 that is connected by an inlet duct 104 to a stack, or other conduit, in which gases produced by another process are directed toward the environment or another device that is not a part of the stack gas decontamination system 100. The other process may comprise a combustion or other similar process, such that the gases directed by the stack, or other conduit, comprise combustion by-product gases, including, but not limited to, sulfur dioxide (S0₂) and nitrogen oxides (NO_x). The first chamber 102 is adapted and appropriately configured to receive all, or a portion, of the gases traveling through the stack, or other conduit, via the inlet duct 104 as inlet gas stream 106. Generally, the first chamber 102 comprises a vessel or tank-like structure having a volume of several cubic meters to several tens of cubic meters.

[0016] The first chamber 102 is connected to an ammonia source 108 by a pipeline 110 for the receipt of ammonia (NH₃) therefrom during operation. The ammonia source 108, generally, comprises a pressurized ammonia tank and the pipeline 110, generally, includes one or more regulator(s) and/or control valve(s) therein to appropriately meter the flow of ammonia into the first chamber 102. A sprayer 112, adapted to produce a water spray 114, is attached to a wall of the first chamber 102 in a manner that enables the sprayer 112 to direct the water spray 114 into the first chamber 102 at an appropriate location, direction, and spray pattern. The sprayer 112 is connected to a water source 116 via a pipeline 118. Generally, the water source 116 comprises a water tank that may or may not be pressurized, while the pipeline 118 includes one or more regulator(s) and/or control valve(s) therein to appropriately control the flow of water to the sprayer 112. [0017] The stack gas decontamination system 100 also comprises a second chamber 130 that is connected to the first chamber 102 by a connecting duct 132 for the receipt of a gas stream 134 from the first chamber 102 having a mixture of gases, including, without limitation, sulfur dioxide (S0₂), nitrogen oxides (NO_x), ammonia (NH3), and water vapor (H₂0). The gas stream 134 includes amounts, or concentrations, of ammonia (NH₃) and water vapor (H₂0) appropriate for further processing and amounts, or concentrations, of sulfur dioxide (SO₂) and nitrogen oxides (NO_x) present in inlet gas stream 106. The second chamber 130 is configured to implement a first stage of treatment, or decontamination, of gas stream 134 (and, hence, of the gases of inlet gas stream 106) in an appropriate ammonia (NH₃) and water vapor environment (H₂0) (i.e., created by the introduction of ammonia (NH₃) and water vapor (H₂O) into the gases of the inlet gas stream 106 in the first chamber 102) at a pressure near atmospheric pressure by gas discharge such that a substantial portion of the sulfur dioxide (S0₂) and a small portion of the nitrogen oxides (NO_x) are removed from the gases of gas stream 134.

[0018] The second chamber 130 includes a plurality of electrodes 136 extending therewithin (i.e., described in more detail below with respect to Figs. 2, 3, and 4) that are electrically connected to a high-voltage power supply 138 by high-voltage cables 140. The electrodes 136 are operable to induce gas discharge of the gases of gas stream 134 therebetween. The high-voltage power supply 138 is configured to produce an appropriate amount of power for consumption by the electrodes 136 and may comprise a direct current (DC), pulse, or radio frequency (RF) power supply. The second chamber 130, generally, comprises a vessel or tank-like structure through which the gases of gas stream 134 (and, hence, of the inlet gas stream 106) flow and are treated at near atmospheric pressure. Generally, the second chamber 134 comprises a vessel or tank-like structure having a volume of several cubic meters to several tens of cubic meters. Also generally, the electrodes 136 may have a distance therebetween of up to tens of centimeters. [0019] Additionally, the stack gas decontamination system 100 comprises a first particle accelerator 150 that is connected to the second chamber 130, via waveguide 152, at an appropriate location. The first particle accelerator 150 is operable to "light" (e.g., excite and maintain) the gas discharge between the electrodes 136 that are powered by high-voltage power supply 138. Such lighting is necessary because self-sustained gas discharge (e.g., burning without lighting) in large chambers, or volumes, such as second chamber 130 at a pressure close to atmospheric pressure is, generally, not possible. Thus, the first particle accelerator 150 supports the non-self-maintained gas discharge between the electrodes 136 by irradiating the gases of gas stream 134 (and, hence, of the inlet gas stream 106) to cause preliminary ionization of the gases. Due to such irradiation and preliminary ionization, the gas discharge between the electrodes 136 is not only made possible, but is made more stable and uniform. [0020] Generally, the first particle accelerator 150 comprises an electron accelerator that is operable to produce a low-power electron beam and to direct the electron beam, via waveguide 152, into the gas between electrodes 136. More specifically, the first particle accelerator 150 may comprise a pulsed RF electron accelerator. It should be noted, however, that the gas discharge receives most of its energy from high-voltage power supply 138 and not from particle accelerator 150. It should be also noted that while the present invention has been described herein as being embodied with a first particle accelerator 150 comprising an electron accelerator, the scope of the present invention includes the use of a first particle accelerator 150 of a different type and more than particle accelerator in lieu of the first particle accelerator 150. Additionally, it should be noted that, in alternate embodiments of the present invention, gamma radiation from an isotope source such as, but not limited to, Co⁶⁰ may be employed to light and stabilize the gas discharge between electrodes 136. [0021] The stack gas decontamination system 100, as illustrated in Fig. 1, further comprises a third chamber 160 and a second particle accelerator 162. The third chamber 160 is connected to the second chamber 130 by a connecting duct 164 that directs the gases treated in the second chamber 130 into the third chamber 160 as a gas stream 166 that includes ammonia (NH₃) and water vapor (H₂0), and amounts, or concentrations, of sulfur dioxide (S0₂) and nitrogen oxides (NO_x) that are reduced in comparison to the amounts, or concentrations, of sulfur dioxide (S0₂) and nitrogen oxides (NO_x) present in the gases of gas stream 134 leaving the first chamber 102. The third chamber 160 is configured to receive the gases of gas stream 166 and to implement a second stage of processing, treatment, or decontamination, on the gases of gas stream 166 (and, hence, of the gases of inlet gas stream 106) in an appropriate ammonia (NH₃) and water vapor environment (H₂0) (i.e., created by the introduction of ammonia (NH₃) and water vapor (H₂0) into the gases of the inlet gas stream 106 in the first chamber 102) at a pressure near atmospheric pressure via ion-molecular reactions that are initiated and maintained by irradiation of the gases by an electron beam of accelerated electrons produced by the second particle accelerator 162 and delivered to the third chamber 160 by waveguide 168 attached thereto. Generally, the second particle accelerator 162 comprises a direct current (DC) electron accelerator that is operable to irradiate the gases of gas stream 166 with an electron beam. It should be understood that while the present invention has been described herein as being embodied with a single, direct current, second particle accelerator 162, the scope of the present invention includes the use of a second particle accelerator 162 of a different type and the use of multiple particle accelerators in lieu of a single, second particle accelerator 162.

[0022] The third chamber 160 is connected to an exit duct 170 that is configured to direct the flow of gases treated, or decontaminated, in the third chamber 160 as an exit gas stream 172 to the atmosphere or to a device that is not part of the stack gas decontamination system 100. In comparison to the gases of gas stream 166 that enter the third chamber 160, the gases present in exit gas stream 172 include an amount, or concentration, of nitrogen oxides (NO_x) that has been substantially reduced and an amount, or concentration, of sulfur dioxide (S0₂) that has been further reduced, by the ion-molecular reactions that occur in the third chamber 160 during operation of the stack gas decontamination system 100.

[0023] Fig. 2 displays a front, elevational, schematic view of the second chamber 130 of the. stack gas decontamination system 100 in accordance with the exemplary embodiment of the present invention. The second chamber 130 has a first side 200 and an opposed second side 202, and has a top 204 and an opposed bottom 206. The first and second sides 200, 202 define a longitudinal axis 208 extending therebetween. The electrodes 136 are, generally, elongated and are positioned within the second chamber 130 such that the longest dimension of the electrodes 136 extends in a direction substantially parallel to the longitudinal axis 208 of the second chamber 130 (and, hence, in a direction substantially parallel to the direction of flow of gas stream 134 past the electrodes 136). As illustrated by arrows in Fig. 2, the second chamber 130 is configured so that gas stream 134 is received by the second chamber 130, via connecting duct 132, through an opening at the first side 200 thereof and exits the second chamber 130 as gas stream 166, via connecting duct 164, through an opening at the second side 202 thereof. Within the second chamber 130, the gases of gas stream 134 flow adjacent to and between the electrodes 136 in a direction substantially parallel to the longitudinal axis 208 of the second chamber 130. As described herein, while flowing within the second chamber 130, the gases of gas stream 134 are irradiated by electrons of an electron beam emitted from the first particle accelerator 150 and delivered to the second chamber 130 via a waveguide 152. The electrons of the electron beam, as illustrated in Fig. 2 by arrows 210, are emitted into the second chamber 130 through an opening at the top 204 thereof and travel, generally, in a direction toward the second chamber's bottom 204 and perpendicular to the second chamber's longitudinal axis 208. [0024] Fig. 3 displays a side, elevational, schematic view of the second chamber 130 of the stack gas decontamination system 100, according to the exemplary embodiment of the present invention, illustrating a first configuration of a plurality of electrodes 136 therein. In such first configuration, each electrode 136 comprises a substantially planar plate oriented such that its shorter dimension extends, generally, between the second chamber's top and bottom 204, 206 in a direction, generally, perpendicular to the second chamber's longitudinal axis 208. Electrons of the electron beam, as illustrated in Fig. 3 by arrows 210, are emitted into the gases present between the electrodes 136, thereby lighting the gas discharge between the electrodes 136. Such electrodes 136 are often referred to as "flat tip high-voltage electrodes". [0025] Similarly, Fig. 4 displays a side, elevational, schematic view of the second chamber 130 of the stack gas decontamination system 100, according to the exemplary embodiment of the present invention, but illustrating a second configuration of a. plurality of electrodes 136 therein. In such second configuration, the plurality of electrodes 136 includes a plurality of first electrodes 136_A and a plurality of second electrodes 136β. The electrodes 136 are arranged in adjacent columns 212 of electrodes 136 with electrodes 136 in odd-numbered columns 212A comprising first electrodes 136A and with electrodes 136 in even- numbered columns 212B comprising second electrodes 136β. Each first electrode 136A comprises a substantially planar plate oriented such that its shorter dimension extends, generally, between the second chamber's top and bottom 204, 206 in a direction, generally, perpendicular to the second chamber's longitudinal axis 208. Generally, first electrodes 136_A comprise flat tip high- voltage electrodes described above with respect to Fig. 3. Each even-numbered column 212_B comprises multiple second electrodes 136B arranged such that each second electrode 136B extends in a direction substantially parallel to the second chamber's longitudinal axis 208 and is separated by a gap 214 from another second electrode 136B of the even-numbered column 212_B. Generally, second electrodes 136B comprise core, or wire, electrodes. Electrons of the electron beam, as illustrated in Fig. 4 by arrows 210, are emitted into the gases present between the columns 212 of electrodes 136, thereby lighting the gas discharge between the electrodes 136. [0026] It should be understood that electrodes 136, in either the first or second configuration thereof, may also include coaxial cylinders and may include various combinations of flat plate, coaxial cylinder, and rod (e.g., wire) electrodes. It should also be understood that the polarity of the voltages applied to the electrodes 136 may be alternated.

[0027] In operation, the first chamber 102 of the stack gas decontamination system 100 receives all, or a portion, of the gases (including, without limitation, sulfur dioxide (S0₂) and nitrogen oxides (NO_x)), traveling through a stack, or other conduit, of an industrial enterprise or facility via inlet duct 104 as inlet gas stream 106. The flow rate of inlet gas stream 106 may be up to 10⁶ cubic meters/hour. Inlet duct 104 directs the inlet gas stream 106 into the first chamber 102 where ammonia (NH3) from ammonia source 108 is mixed into the gases of the inlet gas stream 106. Concurrently, water (H₂0) from water source 116 is sprayed into the gases of the inlet gas stream 106 by sprayer 112, thereby adding water vapor to the gases of the inlet gas stream 106 and cooling the gases for further processing. After the addition of ammonia (NH₃) and water (H₂O) to the gases of the inlet gas stream 106, the inlet gas stream 106 exits the first chamber 102 and flows into the second chamber 130, via connecting duct 132, as gas stream 134.

[0028] Inside the second chamber 130, the ammonia (NH₃) and water

(H₂O) create a moist, ammonia-laden environment having a pressure of approximately atmospheric pressure. Gas stream 134 is then processed in a first stage of processing, treatment, or decontamination, therein by applying high- voltage power from high-voltage power supply 138 to electrodes 136 of the second chamber 130. The voltage between electrodes 136 should not, however, exceed 100-200 kV. Concurrently, the gases of gas stream 134 present between the electrodes 136 are irradiated with an electron beam of accelerated electrons emitted by the first particle accelerator 150 and delivered to the second chamber 130 by waveguide 152. The energy of the accelerated electrons lights the gas discharge between the electrodes 136 such that the preliminary ionization of the gases between the electrodes 136 in conjunction with the high-voltage power provided to the electrodes 136 produces a stable, uniform gas discharge therebetween instead of an, otherwise, non-self maintained gas discharge that may occur in the absence of an electron beam of accelerated electrons. The preliminary ionization and uniform gas discharge reduce the amounts, or concentrations, of sulfur dioxide (S0₂) and nitrogen oxides (NO_x) (and volatile organic compounds (VOCs), if any) present in the gases of gas stream 134 such that the gases of gas stream 166 exiting the second chamber 130 include 5-10% of the sulfur dioxide (S0₂) and 80-95% of the nitrogen oxides (NO_x) present in the gases of gas stream 134.

[0029] Upon exiting the second chamber 130, the gases of gas stream

166 flow through connecting duct 164 and into the third chamber 160 where they are further processed, treated, or decontaminated, in a second stage of treatment. Inside the third chamber 160 and similar to the environment inside the second chamber 130, the ammonia (NH3) and water (H₂0) create a moist, ammonia-laden environment having a pressure of approximately atmospheric pressure. The gases of gas stream 166, once inside and while flowing through the third chamber 160, are irradiated by an electron beam of accelerated electrons produced by the second particle accelerator 162 and delivered to the third chamber 160 by waveguide 168. The energy of the accelerated electrons initiates and maintains ion-molecular reactions within the third chamber 160 that further reduce the amounts, or concentrations, of sulfur dioxide (SO2) and nitrogen oxides (NO_x) (and volatile organic compounds (VOCs), if any) present in the gases of gas stream 166. After such irradiation and such ion-molecular reactions, the gases of gas stream 166 exit the second chamber 130 through exit duct 170 as exit gas stream 172 and are directed into the atmosphere or to a device that is not part of the stack gas decontamination system 100. As a consequence of the second stage of treatment, the gases of exit gas stream 172 include 2-8% of the sulfur dioxide (S0₂) and 15-35% of the nitrogen oxides (NO_x) present in the gases of gas stream 134. [0030] By separating the processing, treatment, and decontamination of the gases of inlet gas stream 106 into dual-stages, or dual-steps, the majority of the sulfur dioxide (SO2) in such gases is removed in the first stage prior to the removal of the nitrogen oxides (NO_x) in the second stage, thereby reducing the energy requirements for such removal of nitrogen oxides (NO_x). It should be noted, however, that the scope of the present invention includes similar methods in which the nitrogen oxides (NO_x) are removed prior to the removal of sulfur dioxide (SO2). It should also be understood that the scope of the present invention includes other methods that comprise cascaded stages similar to those stages described herein.

[0031] Whereas this invention has been described in detail with particular reference to an exemplary embodiment and variations thereof, it is understood that other variations and modifications can be effected within the scope and spirit of the invention, as described herein before and as defined in the appended claims.

Claims

CLAIMSWhat is claimed is:

1. A system for removing sulfur dioxide and nitrogen oxides from a gas stream including sulfur dioxide and a nitrogen oxide, said system comprising: a plurality of electrodes operable to produce a gas discharge in a gas stream flowing between said electrodes during a first stage of processing, said gas stream including sulfur dioxide and a nitrogen oxide; a first particle accelerator adapted to emit an electron beam during said first stage of processing for lighting said gas stream; and, a second particle accelerator configured to emit an electron beam into said gas stream during a second stage of processing for initiating chemical reactions in said gas stream.

2. The system of Claim 1, wherein said first particle accelerator is further adapted to direct said electron beam of said first particle accelerator into said gas stream between said electrodes.

3. The system of Claim 1 , wherein said first particle accelerator comprises a pulsed RF electron accelerator.

4. The system of Claim 1, wherein said second particle accelerator comprises a direct current electron accelerator.

5. The system of Claim 1 , wherein said gas stream includes ammonia and water vapor.

6. The system of Claim 1, wherein said gas stream has a pressure slightly greater than atmospheric pressure.

7. The system of Claim 1, wherein said electrodes of said plurality of electrodes have a substantially planar shape.

8. The system of Claim 1, wherein said electrodes of said plurality of electrodes have a substantially cylindrical shape.

9. The system of Claim 1 , wherein said plurality of electrodes includes a first plurality of electrodes of a first type and a second plurality of electrodes of a second type different than said first type.

10. The system of Claim 9, wherein electrodes of said first plurality of electrodes and electrodes of said second plurality of electrodes are arranged in alternating columns of electrodes.

11. The system of Claim 1 , wherein electrodes of said plurality of electrodes are elongated and have a longest dimension that extends in a direction substantially parallel to a major direction in which said gas stream flows.