Patent Publication Number: US-RE39596-E

Title: Method and apparatus for the destruction of volatile organic compounds

Description:
This application is a division of application Ser. No. 08/538,692, filed Oct. 3, 1995, now U.S. Pat. No. 5,592,811. 
    
    
     TECHNICAL FIELD 
     This invention relates generally to a method and apparatus for the destruction of hazardous materials, such as volatile organic compounds, and more particularly, to the destruction of volatile organic compounds through the use of a turbine engine in order to produce power. 
     BACKGROUND OF THE INVENTION 
     Increasingly over the past half century, air quality has become an issue of public concern. Over this period, the scientific community has steadily improved its understanding of the origins of the air pollution that is apparent over most major U.S. cities. A large part of this air pollution is attributable to the release of volatile organic compounds into the atmosphere. As a result, the reduction of the releases of volatile organic compounds has become an increasingly important part of the overall strategy to improve air quality. 
     The most familiar volatile compound reduction technique is the control of fuel vaporization by vapor recovery techniques, first on automobiles and now on gasoline stations located in nonobtainment areas. As a result, the steady year over year increase in U.S. releases of these compounds has leveled off and is now even declining. 
     Manufacturing sites are responsible for approximately 8.5 million tons of volatile organic compound emissions annually. Solvent vaporization or in some cases, hydrocarbon byproducts, are key to the manufacturing process of many of the items used regularly in daily life. The manufacture of familiar consumer products results in the release into the atmosphere of significant amounts of organic compounds such as pentane, ethanol, methanol, ethyl acetate, and many others. The control of volatile organic compounds is essential to the environmentally friendly manufacture of these products, and thus, there remains a struggle with the cost of control versus the loss of competitiveness. 
     The most common control method in use today is the thermal oxidizer. In connection with this method, the volatile solvent is released in amounts generally less than a few thousand parts per million into the plant air system. This air is then selectively collected and fed into a combustion chamber where it is mixed with enough natural gas to sustain combustion. It is then ignited in a large chamber that incinerates the volatile solvent, as well as, the natural gas, thereby producing carbon dioxide and water vapor as the primary products of combustion. These oxidizers are large, complicated devices that represent a major capital expense and require significant amounts of electricity and gas to operate. While heat can sometimes be recovered, generally speaking, thermal oxidizers represent a significant economic loss to the businesses using them. In a typical U.S. industrial plant, the cost of operating this type of device easily adds 25%, and often much more, to the yearly energy bill. 
     Another current control technology uses solvent recovery methods that pass the air from the plant through an activated charcoal filter. Periodically, the charcoal is heated, driving off highly concentrated volatile compounds into a chilled condensing system. The output is a liquid organic compound often requiring hazardous waste treatment. The cost of operation, as well as the initial capital costs, are significantly higher than the thermal oxidizer, thereby making this control technology less attractive for the majority of industrial sites. 
     Accordingly, an efficient and cost effective device for the destruction of volatile organic compounds is needed. 
     SUMMARY OF THE INVENTION 
     A system for the destruction of volatile organic compounds according to the present invention addresses the shortcomings of the prior art. 
     In accordance with one aspect of the present invention, a system for the destruction of volatile organic compounds comprises a power generator, such as a gas turbine engine, which is provided with a reaction chamber driven by a combustion device. The system further comprises a primary inlet to the combustor for supplying a primary fuel. A secondary fuel is also supplied to the combustor and to the reaction chamber. The secondary fuel comprises air and an amount of a volatile organic compound. The system further includes a compressor, typically the compressor of the power generator, for compressing the secondary fuel. The reaction chamber is preferably connected to an exit of the combustor to allow for stoichiometric reaction of the two fuels after they are mixed together. 
     In accordance with a further aspect of the present invention, the power generator drives a recovery system that generates electricity. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING FIGURES 
       The present invention will hereinafter be described in conjunction with the appended drawing figures, wherein like designations denote like elements, and: 
         FIG. 1  is a simplified schematic drawing of a destruction device in accordance with the present invention; 
         FIG. 2  is a schematic drawing of a device of the type shown in  FIG. 1  as utilized in an exemplary plant layout; 
         FIG. 3  is a cross-sectional view of a combustor used in connection with the destruction device of  FIG. 2 ; 
         FIG. 4  is a partial cross-sectional view of the combustion device and reaction chamber of the destruction device of  FIG. 2 ; 
         FIG. 5  is a cross-sectional view of the compressor of the destruction device of FIG.  2 ; 
         FIG. 6  is a schematic drawing of an alternative plant layout of a destruction device in accordance with the present invention; and 
         FIG. 7  is a further alternative embodiment of a mobile layout of a destruction device in accordance with the present invention. 
         FIG. 8  is schematic drawing of a two stage compressor of the destruction device of  FIG. 2.   
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EXEMPLARY EMBODIMENTS 
     While the way in which the present invention addresses the various disadvantages of the prior art designs will be discussed in greater detail hereinbelow, in general, the present invention provides a volatile organic compound (VOC) destruction device which includes a power generator such that the effective elimination of VOC&#39;s also results in the co-generation of power. The power so produced can be converted into electricity, which can in part drive the destruction device as well as produce power for other uses. 
     With reference to  FIGS. 1 and 2 , a VOC destruction device  10 , in accordance with a preferred embodiment of the present invention, suitably includes a power generator  12  which is driven by a fuel system  14 . Fuel system  14  preferably comprises a combustor  16  and a reaction chamber  18 . As will be discussed in greater detail hereinbelow, in operation, VOC destruction device  10  utilizes natural gas or any other suitable fuel as a primary fuel supply in a conventional manner. However, in accordance with the present invention, this primary fuel is suitably mixed with a secondary fuel comprising air and preferably VOCs. This fuel mixture of primary and secondary fuels is consumed by power generator  12 . 
     In accordance with a preferred embodiment of the present invention, power generator  12  preferably comprises a gas turbine engine, for example an AlliedSignal IE-831 engine, which is produced by AlliedSignal Aerospace, Phoenix, Ariz. has been found to be suitable. However, it should be recognized that any suitable engine can be used in the context of device  10 , provided such engine can be suitably employed in the generation of power. 
     With continued reference to  FIG. 2 , power generator (engine)  12  is preferably of a conventional design. For example, engine  12  suitably includes, in spaced relation, a generator  20 , a gearbox  22 , a compressor  24  and a turbine  26 . Turbine  26 , also preferably of a conventional design, suitably includes a power turbine (not shown) connected to shaft  28 . As will be appreciated, shaft  28  is suitably connected to generator  20 , gearbox  22  and compressor  24 . 
     In accordance with the present invention, VOC destruction device  10  can be utilized to concurrently destroy VOC&#39;s and realize the fuel value of such VOC&#39;s produced from a variety of different environments. In this context, the term “VOC” is used broadly to refer to carbon containing compounds, such as hydrocarbons, dioxins, alcohols, ketinesaldehydes, ethers, organic acids, halogenareated forms of the foregoing and the like. For example, as used herein, the term VOC may refer to pentane, n-ethylmorphilin, toluene, ethanol, methanol, decabromodiphenyloxide, ethyl acetate, benzene, polystyrene and the like. Such VOC&#39;s or similar chemical compounds are typically produced from the evaporation of chemicals used in and generated by basic industrial processes to produce plastics, pharmaceuticals, bakery products, printed products and the like. A particularly preferred application of the present invention is in the area of control VOC&#39;s produced during the production of expandable polystyrene (i.e. the process to make “styrofoam”) where the primary emission is the VOC pentane. 
     Device  10  can be employed to destroy VOC&#39;s which can be collected from the plant as whole, from special isolated or hooded areas, from dryers or from a VOC concentrator utilized in such plants. In the context of the present invention, air from one or more of these environments or areas is referred to as “VOC laden air”. It should be appreciated that the amount of VOC present in such air may vary from small amounts or none to larger amounts, over time and as conditions in the plant change. As with typical prior art methods of destroying VOCs or such, the present invention may be employed even over periods of time when the VOC level is small or nonexistent. As such, the term VOC laden air includes air that from time to time may not include a significant quantity (or any amount) of a VOC. 
     VOC laden air, such as air laden with pentane resulting from the manufacture of expandable polystyrene, is first collected and thereafter suitably passed into device  10 . While such VOC laden air may be collected in any conventional manner for use in connection with the present invention, preferably, in such a process, the VOC laden air is ducted from the plant via one or more air ducts. These ducts are directly or indirectly connected to an inlet duct  40  (see  FIG. 1 ) which provides VOC laden air to destruction device  10 . 
     In accordance with a preferred aspect of the present invention, power generator  12  draws in such VOC laden air together with fuel, the combustion gases of both which flow at high velocity into turbine  26  and thereby drive turbine  26 . As previously briefly mentioned, the primary fuel utilized as the power source in accordance with the present invention may comprise natural gas; alternatively, diesel oil, jet fuel, methane or any other fuel material may be utilized in an amount sufficient to sustain combustion in combustor  16 . 
     The secondary fuel comprising the VOC laden air is generally much leaner than the primary fuel. Generally speaking, the secondary fuel has a VOC concentration in the range of 0% to 1%. This 1% maximum corresponds to approximately 10,000 parts per million, depending on the type of organic compound involved. Typically this will comply with OSHA regulations as the maximum concentration allowed within plant air in order to prevent the possibility of an explosion within the plant, and in the event permissible limits are exceeded, the concentration can be reduced. However, it should be appreciated that system  10  is capable of handling higher VOC concentrations, as may be desirable in some applications. 
     With reference to  FIG. 1 , a simplified schematic view of destruction device  10  is shown. As shown, VOC laden air from inlet duct  40  is suitably directed to power generator  12 , and in particular, compressor  24  thereof. Preferably, the temperature of the inlet air A, i.e. the VOC laden air, is at a temperature of less that about 130° F. To this end, a temperature control system  42  is suitably positioned to measure the temperature of the inlet air and in the event the temperature exceeds about 130° F., the air is cooled through a cooling system  44 . As will be appreciated by those skilled in the art, cooling system  44  may suitably comprise an air or water heat exchanger suitably configured to cool the temperature of inlet air to a temperature in the range of about 59° to about 130° F. 
     Once the temperature of inlet air A is within a suitable range, such inlet air A is passed through a control valve  46  which is suitably provided with a VOC monitor  48 . As will be discussed in greater detail below, monitor  48  measures the level of VOC within inlet air A. This VOC level measurement, as will be described in greater detail below, is utilized to adjust, as appropriate, the ratio of primary and secondary fuels which are fed into combustor  16 . Regulator  46  suitably regulates the flow of air which is drawn into compressor  24 . 
     When device  10  is placed in initial operation, generator  20  is utilized to initially drive compressor  24  (as well as turbine  26 ) to suitably draw inlet air A into compressor  24 . As operation of device  10  continues, the power drawn from generator  20 , through gearbox  22 , may be suitably decreased and thereafter compressor  24  is, at least in part, and preferably entirely driven by the power generated through operation of device  10 , and in particular, through the generation of energy effected by turbine  26 . 
     As discussed briefly above, compressor  24  suitably comprises the compressor of power generator  12 . With momentary reference to FIG.  5    8 , compressor  24  preferably comprises alternate respective sets of rotating blades  56   and stationary blades  58  . Rotating blades  56   are suitably rotated through rotation of shaft  28 , which is briefly noted above, is initially activated by generator  20 . In accordance with a preferred aspect of the present invention, compressor  24  comprises a multi-stage compressor, more preferably a two stage compressor, i.e. there are at least 2 rotating blades (impellers)  56  within the body of compressor  24  . 
     As will be recognized by those skilled in the art, inlet air A drawn into compressor  24  is suitably compressed to pressures ranges from about 4 to about 30 atmospheres, and preferably to about 9 atmosphere. This compression raises the temperature of inlet air A, and thus the secondary fuel, to ideally about 600° F., but suitably within the range of about 550° F. to about 650° F. The compressed air B then exits compressor  24  through outlets  57 A,  57 B and preferably enters reaction chamber  18  through inlets  59 A,  59 B. 
     With continued reference to  FIG. 1 , compressed air B is suitably directed to a flow valve  50  which is provided with a monitor  52 . Valve  50  suitably controls the amount of compressed air B which is provided to reaction chamber  18  and combustor  16 . 
     As shown best in  FIG. 1 , a primary fuel inlet  70  provides primary fuel C to combustor  16  through a flow valve  72 . Flow valve  72  preferably includes a monitor  74  to monitor the volume of fuel which is provided to combustor  16 . As will be described in greater detail hereinbelow, fuel C and a limited amount of compressed air B (including the secondary VOC fuel) is suitably provided to combustor  16 , the remaining portion of the secondary fuel being provided to reaction chamber  18 . In accordance with a particularly preferred aspect of the present invention, the combination of combustor  16  and reaction chamber  18  is effective to substantially destroy the VOC within compressed air B and provide a mixed combustion gas stream D having a temperature suitable to activate the nozzle and turbine stages of gas turbine  26 . In accordance with a preferred aspect of the present invention, the mixed-out temperature of mixed stream D provided to turbine  26  is in the range between about 1500° F. and about 2300° F., preferably about 1850° F. 
     In a conventional fashion, mixed stream D is directed to turbine  26 . Turbine  26  of the type generally described above, is initially started by cranking it over with a starter (not shown) to produce air flow through the compressor. At the appropriate speed, fuel C is permitted to flow into combustor  16 . However, once device  10  is in operation, mixed stream D suitably powers turbine  26  in a manner such that the output E from turbine  26  is suitably harnessed and utilized in subsequent operation of device  10 , as well as in connection with the production of power for other applications. 
     With reference to  FIGS. 3 and 4 , the way in which reaction chamber  18  and combustor  16  cooperatively work to effectively destroy the VOC&#39;s in the VOC laden air in a manner to suitably drive power generator  12  will now be described in greater detail. 
     Reaction chamber  18  preferably comprises a double walled vessel having a main, inner wall  60  and an outer wall  62  that envelopes inner wall  60 . The chamber  64  defined by walls  60  and  62  is suitably configured and positioned in proximity to compressor  24  to receive compressed air B. Preferably, and with reference to  FIGS. 4 and 5 , chamber  64  receives compressed air B (containing the secondary fuel) from outlets  57 A,  57 B of compressor  24 . Chamber  64  extends about the periphery of reaction chamber  18 . Further, in accordance with a preferred aspect of the present invention, chamber  64  also suitably communicates with combustor  16  in the region of respective openings  67 A and  67 B by way of a plurality of inlets  69 , as well as wall  60  by way of tube outlets  124 ,  126 . Thus, compressed air B is, in accordance with at least one aspect of the present invention, suitably provided to the combustor  16  and also directly to chamber  64  by way of tubes  116 ,  118 , as will be discussed in further detail below. 
     With reference to  FIG. 3 , combustor  16  preferably comprises a hot wall type thermally insulated combustor. Preferably, combustor  16  comprises an outlet wall  80  within which a conventional combustion device  82  is suitably orientated. An inlet  84  communicates with combustion device  82  to advantageously effect combustion of fuel C. As previously briefly mentioned, fuel inlet C is preferably directed from fuel supply  70  through fuel control valve  74  and compressed air B is provided to combustion device  82  through inlets  69 . In accordance with preferred aspects of the present invention, fuel supply C is suitably controlled by a control system  150  such that a sufficient amount of primary fuel C is provided to combustion chamber to effectively maintain an appropriate equivalence ratio (ER) thereby enabling stoichiometrically correct combustion. As shown best in  FIGS. 3 and 4 , the outlet  86  of combustor  16  suitably communicates with the interior of reaction chamber  18 . 
     Combustor  16  may be attached to reaction chamber  18  in any convenient manner. For example, combustor  16  can be fixably attached to chamber  18  such that outlet  86  of combustor  16  directly communicates with an opening of reaction chamber  18  in an in-line manner. However, in accordance with a preferred aspect of the present invention and as shown best in  FIGS. 3 and 4 , combustor  16  is attached to reaction chamber  18  such that combustor  16  is orthogonal to the central axis X of reaction chamber  18 . In this manner, as will be described in greater detail below, the combination gases exit outlet  86  of combustor  16  tangentially to reaction chamber  18  thereby tending to create a substantially cyclonic flow of the resulting fuel mixture within reaction chamber  18 . While combustor  16  is shown in  FIG. 4  as being attached to reaction chamber  18  tangentially near an end of reaction chamber  18  opposite inlets  59 a,  59 b, it should be appreciated that combustion chamber  16  may be attached in any convenient fashion. For example, combustor  16  may be attached at any angle from about 0° to about 90° from the central axis X of reaction chamber  18  and at any point along a side or the top of reaction chamber  18 . 
     Combustion within combustor  16  takes place in a generally conventional manner, with the exception that compressed air B, i.e. the VOC laden air introduced into the system, is permitted to mix with the primary fuel C within the later stages of combustor  16 . As will be appreciated by those skilled in the art, near inlet  84 , primary fuel C is relatively rich such that it burns under near stoichiometric conditions, typically at a temperature in the range of about 2500° F. to about 3200° F., preferably between about 2800° F. and about 3000° F. and optimally 3000° F. In this region denoted in  FIGS. 3 and 4  as “P”, often referred to as the “primary zone”, a minor portion of secondary fuel, which is contained within the compressed air is suitably mixed with primary fuel thereby creating a fuel mixture of primary and secondary fuels. The minor portion of secondary fuel introduced into the primary-zone P via inlet  69  is about 10% to about 30% of the secondary fuel. If the portion falls much below 10%, the fuel will become too rich and thereby cause “rich blowout.” While the amount of secondary fuel introduced into combustor  16  will vary, in general preferably from about 0 to about 70%, and more preferably from about 0 to about 50% of the fuel necessary to drive power generator  12  is provided by the secondary fuel. 
     The residence time of the gas mixture of primary fuel and secondary fuel within reaction chamber is enhanced due to the preferred configuration of combustor  16  relative to reaction chamber  18 . Specifically, and in accordance with a preferred aspect of the present invention, as the combustion gases exit the combustor at outlet  86 , such gases are directed toward the opposing wall of reaction chamber  18 . The flow pattern which results in the interior of reaction chamber  18  tends to be cyclonic, i.e. creating a spiral pattern. 
     In accordance with a preferred aspect of the present invention, the fuel mixture, comprising primary fuel and secondary fuel is retained in reaction chamber  18  for a sufficient time to effectively burn, i.e. combust the VOC&#39;s contained within the secondary fuel B. Typically, the residence time of the gas mixtures within reaction chamber  18  is on the order of about 0.25 seconds or more. In accordance with a preferred design of the present invention, the tangential orientation of the combustor relative the reaction chamber has been found to not only enhance residence time, but also to cause a degree of recirculation within reaction chamber  18  thus further enabling substantially complete destruction of the VOC&#39;s within reaction chamber  18 . 
     In practice, the present invention generally results in an excess of 90%, and typically from between about 95 and 99.5% of the VOC contained within secondary fuel B being effectively broken down into water vapor and carbon dioxide. As will be appreciated, and as will be discussed in greater detail below, through effective operation of device  10 , substantially all of the VOC&#39;s contained within the inlet air A, and thus compressed air B, are thus effectively destroyed within reaction chamber  18  and/or combustor  16 . 
     Preferably, flow channels  112 ,  114  of system  110  each comprise respective tubes  116  and  118 . Preferably, tubes  116  and  118  are suitably attached to reaction chamber  18  at  116 A,  118 A and are in fluid communication with chamber  64  at outlets  124  and  126 . Tubes  116  and  118  each preferably include respective valves  120  and  122 , which may comprise any conventional flow control valve, such as a general poppet-type valve or the like. Tubes  116 ,  118  are in fluid communication with duct  65 , which is in fluid communication with chamber  64 , such that when valves  120 ,  122  are opened, the pressure differential between chambers  18  and  64  pushes a portion of the compressed air B out of chamber  64  through duct  65  and into tubes  116 ,  118 . This portion of compressed air B then travels through the tubes  116 ,  118  and exits through outlets  124 ,  126  directly into chamber  60 , causing air B to thereby bypass the combustor  16 . In a preferred embodiment, when the valves  120 ,  122  are closed, all of compressed air B enters combustor  16  in the region of openings  67 A and  67 B via inlets  69 . 
     Preferably, as shown, channels  112  and  114 , as well as duct  65 , each comprise a single tube that allow for the adequate bypass of compressed air B from chamber  64  directly into reaction chamber  18 . However, other arrangements for accomplishing this objective easily can be devised and employed in the context of the present invention. Due to size considerations, generally the number of channels  112 ,  114  are minimized to two or three, and preferably even one; however, additional channels may be employed as desired. 
     Inlet air control system  110  can be activated manually or through the computer control associated with control system  150 , which will now be described. 
     Preferably, control system  150  is a computer based system suitably configured and arranged to control, among other things, power generator  12  and fuel supply C, as well as inlet and outlet air from device  10 . In general, control system  150  operates in a conventional manner to control power generator  12  including, among other things, compressor  24  and turbine  26 . Further, in a conventional fashion, control system  150  operates to start device  10  initially and monitor operation of device  10  as device  10  begins to operate due to the burning of primary fuel A and secondary fuel C. 
     Control system  150 , however, differs from conventional gas turbine and other industrial engine controls in that system  150  operates to monitor and, as necessary, adjust fuel supplies A and C, as well  25  air control system  110  to achieve optimum levels of efficiency and ensure that device  10  safely and effectively remains operative. Any suitable electronic means that is well known in the art may be utilized for control system  150 . As previously noted, and with momentary reference to  FIG. 1 , control system communicates and utilizes information received from sensors  42 ,  48 ,  52 , and  72 . In addition, one or more sensors  152  may be utilized which are incorporated in proximity to or within reaction chamber  18  or combustor  16 . (While sensor  152  is shown in  FIG. 1  as being outside of both chamber  18  and combustor  16 , its location is only illustrative of its position (or the positions) somewhere within fuel control system  14 ). In cooperation, these sensors provide information reflective of, among other things: VOC level in inlet air (e.g. sensor  48 ); temperature and flow rate of inlet air A, compressed air B, fuel C, mixed stream D and the like; fuel content and volume (e.g. sensor  74 ); power output from device  10 ; and speeds of turbine  26 , with this and other information, control system suitably controls the operation of device  10 . 
     For example, when the power output of power generator  12  drops below an expected level for the measured full consumption of fuel C, thus indicating, for example, that the fuel mixture within combustor  16  may be becoming too lean, control system  150  may activate control system  110 . In such cases, valves  120 ,  122  will be opened thereby creating a pressure difference sufficient to draw compressed air B out of the chamber  64  and into the bypass flow channels  112 ,  114 , which in turn, direct compressed air B into reaction chamber  18  thus preventing its flow into combustor  16 . Operation of control system  150  in this manner prevents the fuel mixture within combustor  16  from becoming too lean, while still allowing for the VOC laden air to be reacted with the primary fuel within reaction chamber  18  to thereby destroy the VOC concentration and retain the VOC fuel value. 
     Stated another way, control system  150 , by monitoring the varying VOC level in inlet air A, and thus the corresponding fuel valve of inlet air, adjusts device  10  for appropriate operation. For example, in the case where inlet air A has a fuel valve in excess of that necessary to drive power generator  12  at idle alone, control system  150  suitably reduces the flow of fuel C and as necessary, activates air control system  110  to prevent generator  12  from operating at excessive speeds and/or combustor from operating at excessively lean or such levels. 
     Control system  150  may also be employed to compensate for the relatively long lag time between fuel introduction and changes in conditions at inlet  90  to turbine  26  caused by reactions taking place within reaction chamber  18 , as well as to monitor or control other aspects of device  10 . 
     In accordance with a further embodiment of the present invention, and with reference to  FIG. 6 , in some cases, it may be desirable to initially treat VOC laden air from a typical plant prior to destroying the VOC&#39;s contained therein. In accordance with this aspect of the present invention, an air treatment system  200  is advantageously employed and communicates with one or more destruction devices, for example respective destruction devices  10 A and  10 B. Destruction devices  10 A and  10 B are in a form similar to device  10  described above. System  200  suitably comprises an inlet  202  which cooperates with, for example, inlet air duct  40 . Inlet air A is thereafter drawn into chamber  203  where inlet air A is both cooled and sampled to determine the level of VOCs in inlet air A. Preferably, one or more sensors  206  are suitably carried within chamber  203  for the purpose of determining the VOC level within inlet air A. 
     In the event inlet air A is determined to be laden with an unacceptable level of VOC, an inlet bypass device  208  opens to allow fresh air into chamber  203 . Preferably, bypass device  208  comprises a shutter valve of conventional design. 
     In addition, inlet air A is suitably cooled to a temperature within an acceptable range. Preferably, such cooling is effected through a heat exchanger system  205 . Preferably system  205  comprises respective heat exchange elements  204 ,  218 , outlet  210  and cooling fan  222 . As will be appreciated by those skilled in the art, element  204  is suitably connected via outlet and duct elements (not shown) to cooling pump  211  and heat exchange element  218  such that cooling fluid is suitably recirculated between elements  204  and  218 . In a conventional manner, system  205  allows for the cooling of inlet air A. Inlet air A once cooled, is passed through a centrifugal separator  212  separating the VOC laden air from any large particles. Once separated, the VOC laden air is communicated to devices  10 A and  10 B, preferably by respective conduits  214  and  216 . As previously briefly mentioned, devices  10 A and  10 B operate in a fashion similar to that of device  10  described above to generate respective exhausts E 1 , E 2  which are released into the plant to provide process heat through respective outlet  230 ,  232 . 
     With reference to  FIG. 7 , a further alternative embodiment of the present invention is shown. With certain applications, it may be desirable to utilize a destruction device in accordance with the present invention in a relatively mobile fashion. As shown in  FIG. 7 , a mobile destruction system  300  suitably comprises a sled  302  upon which a destruction device  10 C is suitably mounted. Destruction device  10 C is suitably configured in a manner similar to that of device  10  described hereinabove. As so configured, device  10 C includes power generator  12  to which reaction chamber  18  and combustor  16  are suitably attached. The output of device  10 C, namely exhaust E 3  is suitably communicated via outlet  303  into a heat recovery air-oil cooler  304 . In accordance with this embodiment of the present invention, a voltage source  306  is suitably provided to provide startup power to device  10 C, as well as power, at least initially, to the other aspects of system  300 . A gas compressor  308  is also suitably mounted to sled  302  for raising gas pressure to levels required by device  10 C. Respective ventilators  310 ,  312  may be also suitably mounted to sled  302 . In addition, a water supply  320  with respective auxiliary units  322 ,  324 ,  326 ,  328  and pump  330  may also be utilized for purposes of water injection into the combustor  16  to control emissions of nitrous oxide. 
     System  300  is suitably controlled through operation of a control system  350  which may be optionally cooled through operation of a refrigeration device  352 . Various other devices such as ventilators, switch and other electronic devices may be also employed, in a conventional fashion, for a effective use of device  10 C in connection with mobile system  300 . 
     Preliminary experimental tests of devices embodying the present invention have indicated that by using the VOC laden secondary fuel, the amount of primary fuel needed to operate the engine is reduced without a loss of energy content in the fuel supply. Accordingly, the use of this volatile organic compound destruction system  10  results in substantially complete destruction of the volatile organic compound while reducing the amount of primary fuel required to operate an engine for the generation of electricity. 
     Thus, it will be appreciated that device  10  provides significant advantages over prior art designs for destruction of VOCs. For example, in accordance with experiments preformed using devices embodying preferred aspects of the present invention, substantial destruction of VOC laden air efficiency (e.g. at rates above 99.5%) at a level of about 6200 ft 3 /min can be obtained with the production of a nominal 525 kw of electrical power. 
     To illustrate the overall impact of the present invention, consider a typical plant using 640,000 kw hours per month with a need to consume 12,000 cubic feet per minute of air laden with 3,500 parts per million of a VOC. Consider further that the plant consumes 97,000 therms of fossil fuel each month. Without control, over 800 metric tons per year of VOC&#39;s are released into the atmosphere. 
     While prior art techniques (e.g. use of a thermal oxidizer) may reduce the emission of less than 50 metric tons per year of VOC&#39;s, use of such devices increases the plant energy consumption to about 125,000 therms per month. 
     In contradistinction, through use of a device embodying the present invention, effective VOC control is enabled with less energy. Specifically, in this example, the energy consumed and therefore, total fossil fuels burned, falls to 81,000 therms per month. Not only are the total operating costs for the plant reduced, but there is also a net reduction in the emission of carbon dioxide, nitric oxide and sulfur oxide. The sum effect of use of the present invention to control volatile organic emissions is thus cleaner air, less fossil fuel consumption and resulting lower costs. 
     It will be understood that the foregoing description is of the preferred exemplary embodiments of the invention, and that the invention is not limited to the specific forms shown. Various modifications may be made in the design and arrangement of the elements set forth herein without departing from the scope of the invention as expressed in the appended claims.