Abstract: This invention is related to a slurry filtration device and the wet lime-gypsum flue-gas desulfurization system comprising a slurry filtration device for the separation (concentration) of gypsum. The slurry filtration device comprises tank that has a slurry supply pipe at its upper part and a filtrate-drain hole at its bottom, a layer of filter sand lying on its bottom, a slurry accumulator arranged on the layer of filter sand, and a vibrator set in said slurry accumulator for vibrating the slurry. The present invention not only improves the solid-liquid separability remarkably but also saves cost and space.

Abstract: Contaminants such as sulfur oxides are removed from flue gas in a low pressure drop, turbulent mixing zone, vertical dry scrubber by channeling the flue gas through a low pressure drop gas distribution means which controls flue gas introduction to the scrubber, along with control of reagent introduction, by treating the flue gas with a finely atomized alkali solution or slurry reagent preferably from a single or multiple array of dual-fluid atomizers. The atomizers create a turbulent mixing zone downstream of the gas distribution means which results in a homogeneous distribution of the alkali solution or slurry reagent in the flue gas. Control means are provided for creating and maintaining the turbulent mixing zone. A transition at the bottom of the dry scrubber is used to entrain any particulates and/or spray dried materials in the bulk gas stream exiting the dry scrubber.

Abstract: This invention relates to a gas-liquid contacting device for efficiently bringing a gas into contact with a slurry solution, and a wet flue-gas desulfurization system using the contacting device. The contacting device incorporated in the system comprises a tank to be supplied with a slurry solution, a set of agitator bars held above the bottom of the tank to be horizontally rotatable, a plurality of gas supply pipes for supplying a gas to the vicinity of the agitator bars, nozzles directed to the region through which the agitator bars rotate or to its vicinity, and a plurality of liquid supply pipes for supplying a liquid to the nozzles.

Abstract: Contaminants such as sulfur oxides are removed from flue gas in a low pressure drop, turbulent mixing zone, vertical dry scrubber by channeling the flue gas through a low pressure drop gas distribution means which controls flue gas introduction to the scrubber, along with control of reagent introduction, by treating the flue gas with a finely atomized alkali solution or slurry reagent preferably from a single or multiple array of dual-fluid atomizers. The atomizers create a turbulent mixing zone downstream of the gas distribution means which results in a homogeneous distribution of the alkali solution or slurry reagent in the flue gas. Control means are provided for creating and maintaining the turbulent mixing zone. A transition at the bottom of the dry scrubber is used to entrain any particulates and/or spray dried materials in the bulk gas stream exiting the dry scrubber.

Abstract: The invention discloses a NOx adsorption and removal apparatus employed in the method of passing NOx containing gas into the adsorber 1 filled with NOx adsorbent to adsorb a specific volume of NOx on the adsorbent, passing hot air into the adsorber to desorb NOx, and regenerating the adsorbent, wherein the adsorber is divided in plural zones arranged parallel in the gas flow direction. In this invention, by regenerating after adsorbing NOx in each zone, the regenerating apparatus can be reduced in size, and the energy may be saved by effective utilization of preheat.

Abstract: A method and apparatus for cleaning a flue-gas stream containing hydrogen chloride and sulfur dioxide are disclosed. The flue gas is treated in a wet cleaner (5), thereafter injected with lime (9) and filtered through a filter (13). The method and apparatus are distinguished by the fact that a pan of the flue-gas is bypassed the wet cleaner (5) through a conduit (15), to join the remainder of the flue-gas stream before the filter (13). In this way, hydrogen chloride in the bypassed stream is reacted with injected lime to form calcium chloride, which promotes the sulfur-dioxide separation upon the injection of lime.

Abstract: An odor control system and method for removing unwanted odorous airborne constituents in which the gas stream is flowed through a compact, boxlike housing having a plurality of sequentially communicating treatment chambers. Gas stream pretreatment is accomplished in a first chamber, in fluid communication with a sump, as the gas flows through a packed bed wetted by suitable chemical reagents. After pretreatment, the gas stream is passed through downstream chambers, also utilizing wetted packed beds. These chambers are in fluid communication with a second, separate sump. Because of the first chamber/separate sump combination, influent gas treatment, by stages, can be accomplished. In this manner, different, contemporaneous chemical treatments are possible, within the single housing, with different chemical reagents utilized as needed. Such treatments are possible even in cases where otherwise incompatible chemical reagents are used.

Abstract: The invention discloses a wet process flue gas desulfurization apparatus and method for use with a tank oxidation system. The apparatus comprises: an absorption tower having a slurry containing a calcium compound which is supplied to the bottom tank, a circulation pump for feeding the slurry in the tank into a flue gas inlet in an upper part of the absorption tank to be in contact with flue gas, and air feed means for feeding air for oxidizing into the tank, thereby absorbing and oxidizing sulfur dioxide in the flue gas by the slurry to obtain gypsum as a byproduct, wherein a vacuum type belt filter is disposed along an outer surface of a side wall of the absorption tower, and part of the slurry that is discharged from the circulation pump is led into the belt filter to be dehydrated, thereby separating and recovering gypsum.

Abstract: A reactor that can be attached to the exhaust manifold of a diesel or gasoline engine, or other internal combustion engines such as a jet engine or a gas turbine to oxidize and burn carbon soot particles, carbon monoxide, and unburned hydrocarbons, and to dissociate nitrogen and sulfur oxides. The reactor has a reaction zone that contains porous heat-retaining foam cells and that is bounded by a porous heat-retaining zone, which in turn is surrounded by ceramic insulation materials to minimize energy losses. Engine exhaust at elevated temperatures and containing some oxygen (air) enters the reaction chamber. By means of impinging heat transfer, thermal radiation enhancement, energy trapping and combustion of engine emissions, temperatures sufficient to oxidize carbon soot particles, carbon monoxide, and unburned hydrocarbons are attained. Harmless product of the oxidation reactions, H.sub.2 O and CO.sub.2 are released from the reactor.

Abstract: An assembly combining a catalytic converter with a spiral muffler, particularly for small internal combustion engines. In series are an expansion chamber, a venturi for air injection, a catalytic converter, and a phase-spreading spiral muffler. The expansion chamber promotes proper operation of the venturi, as well as reducing engine exhaust back pressure and providing some noise reduction. The muffler has a spirally coiled exhaust channel dead-ended at its inner extremity, with an outer extremity serving as a muffled exhaust outlet. A distribution chamber is adjacent the spiral exhaust channel, sharing a common wall therewith, and a plurality of streamlined slotted openings spaced along the exhaust channel at different distances from the muffled exhaust outlet introduce gas from the distribution chamber into the spiral channel.

Abstract: A two chamber regenerative thermal oxidizer comprises an oxidizing chamber and a pair of regenerator chambers. Inlet and outlet valves control fluid flow to and from said regenerator chambers. A transition duct communicates with a contaminated fluid feed duct upstream of the regenerator inlet valves and with the oxidizing chamber of said oxidizer. Electronic control means opens and closes valves, selectively, in a prearranged sequence whereby the inlet and outlet valves in an individual regenerator are never open at the same time, thereby precluding short circuiting of the regenerative chamber, yet all of the inlet and outlet valves to the regenerative chambers are never simultaneously closed thereby to maintain the pressure of fluid flow through said regenerator chambers relatively constant.

Abstract: A method of treating a flow of gas containing oxidized sulphur compounds, such as an exhaust gas from coal combustion, comprising the steps of (i) treating the flow of gas to obtain a first component flow containing at least 30% of the total oxidized sulphur compounds and a second component flow containing at least a part of the remainder of the total oxidized sulphur compounds; (ii) converting the first component flow into a concentrated gas containing at least 2.5% by volume of sulphur compounds; (iii) converting oxidized sulphur compounds in the second component flow into hydrogen sulphide; and (iv) supplying the concentrated gas of step (ii) and the hydrogen sulphide of step (iii) to an apparatus for manufacturing either sulfuric acid, sulphur dioxide or elemental sulphur.

Abstract: A novel electrostatic precipitator includes an electrostatic collector section with discharge electrodes positioned between pairs of grounded collector electrodes, a gas entry port located upstream of said electrostatic collector section, and a transition section between the gas entry port and said electrostatic collector section into which an aqueous acid gas neutralizing agent is sprayed into a gas stream. An additional collector section may be interposed between the gas entry port and the point where the acid gas neutralizing agent is injected into the gas stream. The collector section may comprise alternating charging and short collection sections in which the grounded electrodes of adjoining charger and collector sections are connected. A liquid spray removes particulates collected on the grounded electrodes of the collector sections.

Abstract: An exhaust gas cleaning system includes a pyrolysation channel, a mixing channel downstream of the pyrolysation channel and a reaction channel downstream of the mixing channel. An atomizing nozzle is provided for injecting into the pyrolysation channel an atomized mixture of compressed air and a dilute urea solution. The compressed air and dilute urea solution contacts the exhaust gas stream in the pyrolysation channel wherein the urea decomposes into ammonium and carbon dioxide. Mixers are provided in the mixing channel for forming a homogeneous mixture of the ammonium and carbon dioxide with the exhaust gas. The reaction channel downstream of the mixing channel is provided with at least two catalysts for contacting the homogeneous mixture and removing effluents therefrom.

Abstract: A system for removing SO.sub.2, NO.sub.2, and other contaminants from flue gases uses hydrogen peroxide (H.sub.2 O.sub.2) as the reagent to convert the oxides of sulfur and some of the oxides of nitrogen (NO, NO.sub.2, etc.) to more stable oxidation states. Acids formed as a result of this conversion, namely sulfuric acid (H.sub.2 SO.sub.4) and nitric acid (HNO.sub.3) can then be neutralized with limestone or, alternatively, the sulfuric and nitric acids can be collected and processed for sale as an industrial product.

Abstract: A system for the abatement of industrial process emissions comprises a catalytic oxidizer and a selective catalytic reduction bank integrated into a single housing. The system utilizes at least two regenerative chambers in a controlled abatement process. The integrated system removes volatile organic compounds (VOCs), carbon monoxide (CO), and toxic oxides of nitrogen (NO.sub.x) from the process emissions. The singular housing of the present invention is efficient and eliminates the need for more than one supplementary heat source, while eliminating major pollutants from the emissions.

Abstract: A retractable chemical injection device especially adapted for introducing a chemical reactant solution into a large scale combustion device such as a fossil fuel fired boiler. The device incorporates a lance tube mounted to a elongated frame located outside of the combustion device which enables the lance tube to be extended into and retracted from the combustion device flue gas stream. The lance tube carries a plurality of axially distributed discharge nozzles enabling the chemical reactant entrained in an injection carrier to be ejected from the nozzles. The injection device provides for atomization of the chemical reactant solution before the mixture passes into the lance tube which provides the beneficial effects of cooling the lance tube and providing a uniform distribution of the chemical solution to the distributed discharge nozzles.

Abstract: Limestone is dried for grinding to very fine particles e.g., about 8.mu. or less with more than 99% of the particle by weight less than 44.mu., by utilizing waste heat from the flue gas from a large combustor. The finely-divided calcium carbonate is then introduced dry into a scrubbing tower where it mixes with and renews the slurry employed therein for scrubbing SO.sub.x -laden effluent.

Abstract: Toxic metal vapor phase compounds, and in particular, mercury and cadmium, are removed from waste incinerator combustion gases by contact with dry alkaline material and dry activated carbon followed by solids separation. The resulting gas is subjected to quench/wet scrubbing with recycle hydrochloric acid solution formed in situ by absorption of HCl from the gas. Blowdown liquid withdrawn from the recycle acid liquor, may be recycled to the incinerator or further treated by neutralization, precipitation, and filtration of the precipitated toxic metals.

Abstract: An apparatus for producing a fresh air stream, has a blower connectable at a pressure side with an exhaust gas conduit of an internal combustion engine of a motor vehicle, a fresh air supply element communicatable with the exhaust gas conduit, a check valve provided between the blower and an opening of the fresh air supply element into the exhaust gas conduit, a cut-off arranged in the fresh air supply element between the check valve and its opening into the exhaust gas conduit and having a closing member loaded with a spring force toward a closing position, an actuating member for the closing member, and a bypass branching from the fresh air supply element so that a pressure which builds when the blower operates and is supplied through the bypass to the actuating member for the closing member acts opposite to the spring force.

Abstract: A method and apparatus for controlling emissions of a fossil fuel fired boiler including a high temperature fabric filter house with an SCR catalyst situated therein for receiving flue gases along with an injected ammoniacal compound and sorbent. The sorbent reacts with the SO.sub.x while the ammoniacal compound reduces the NO.sub.x in the presence of the SCR catalyst inside the high temperature fabric filter house. Both the SO.sub.x and the particulates are removed upstream of the SCR catalyst to diminish the problems of SO.sub.2 or SO.sub.3 poisoning of the catalyst and erosion and fouling of the catalyst with the fly ash. Since the sulfur oxides and particulates are removed prior to the heat recovery system, the fouling and corrosion potential are substantially decreased thus allowing the heat recovery system to be operated at a lower outlet flue gas temperature which yields an incremental improvement in energy recovery.

Abstract: The amount of N.sub.2 O emission from a fluidized bed reactor is reduced by adding a hydrogen radical providing additive (e.g. a hydrogen containing fuel such as natural gas or alcohol) to the flue gases discharged from the fluidized bed. Sufficient oxygen is present in the flue gases--either by addition with the additive, or by addition of an excess to the combustion chamber--so that the additive reacts with the oxygen, typically raising the temperature of the flue gases (e.g. from about 700.degree.-900.degree. C. to about 950.degree.-1100.degree. C.) so that N.sub.2 O production is reduced about 10-90%. The additive may be injected in or just prior to a cyclone for separating particles from the flue gases, in a gas discharge immediately after the cyclone (e.g. just downstream of a heat exchanger for cooling the flue gases and flattening the velocity profile of the flue gases), just prior to a superheater of a convection section, or in a combustion chamber just prior to a gas turbine.

Abstract: In the improved apparatus for treating flue gases by irradiation with electron beams, ammonia is added at a position in the direction of the flue gas stream that is upstream of the center of electron beams applied within the reactor and which is not more than 2.5 times the range of electron beams, preferably not more than 2.0 times, more preferably not more than 1.5 times, most preferably from 0.5 to 1.0 times said range. Ammonia is supplied in any one of the following ways; (1) only ammonia is supplied; (2) both ammonia and air are supplied; (3) both ammonia and water are supplied; and (4) ammonia, air and water are all supplied. From an operational viewpoint, ammonia is preferably supplied as diluted in the form of a mixture of heated ammonia and dry air (having preferably a dew point of -15.degree. C. or less at one atmosphere). It is also effective to supply ammonia through pipes that are arranged to contour the spherical divergence of electron beams.

Abstract: A hot gas cleanup system for removing particulates, alkali and sulfur from fuel gas produced by the gasification of coal in a gasifier, especially in an integrated gas turbine gasification power plant. A calcium based sulfur sorbent and an alkali sorbent are injected directly into the fuel gas and then recovered, along with the used sorbent, in a high efficiency, high temperature ceramic barrier filter. The fuel gas is then subjected to further de-sulfurization in a polishing de-sulfurizer supplied with a copper based sulfur sorbent. The used copper based sorbent is regenerated in fluidized bed regenerator. The regenerated sorbent is returned to the polishing de-sulfurizer and sulfur dioxide produced by the regeneration is directed to an oxidizer to which the used and unused sulfur sorbent from the filter is supplied so that the sulfur dioxide can be captured and so that the used sulfur sorbent can be converted to a more stable form for disposal.

Abstract: A device in which a mixture of steam and contaminated air is first of all channelled into an upward stream and that the mixture subsequently flows as a downward stream in a vessel maintained at reduced pressure. The device further includes an arrangement for spraying an alkaline aqueous solution into the downward stream of the mixture of steam and contaminated air. The decontaminated uncondensed gases are thereby removed from the vessel by a forced and adjustable stream which creates and maintains a reduced pressure inside the vessel.

Abstract: A method and apparatus for controlling emissions of a fossil fuel fired boiler including a high temperature fabric filter house with an SCR catalyst situated therein for receiving flue gases along with an injected ammoniacal compound and sorbent. The sorbent reacts with the SO.sub.x while the ammoniacal compound reduces the NO.sub.x in the presence of the SCR catalyst inside the high temperature fabric filter house. Both the SO.sub.x and the particulates are removed upstream of the SCR catalyst to diminish the problems of SO.sub.2 or SO.sub.3 poisoning of the catalyst and erosion and fouling of the catalyst with the fly ash. Since the sulfur oxides and particulates are removed prior to the heat recovery system, the fouling and corrosion potential are substantially decreased thus allowing the heat recovery system to be operated at a lower outlet flue gas temperature which yields an incremental improvement in energy recovery.

Abstract: A system for treating a flue gas includes a first condensing heat exchanger located in the housing for removing heat from flue gas as the flue gas is downwardly passed therethrough. A first collection tank is located in the housing below the first heat exchanger for collecting liquid and particulate. A second heat exchanger is located in the housing for condensibly removing pollutants from the flue gas as the flue gas is upwardly passed through the second heat exchanger. A second collection tank is located in the housing below the second heat exchanger for collecting liquid and particulate.

Abstract: A flue gas emission control system for coal fired boilers use individual units for NO.sub.x, SO.sub.x and particulate removal and provides ammonia injection to all three units from a single source.

Abstract: A two-stage downflow flue gas treatment condensing heat exchanger system allows for flue gas to be passed into a two-stage housing at an upper end of the housing. The flue gas is channeled through a first stage of the housing having a first condensing heat exchanger which cools the flue gas. The flue gas is then channeled through a second stage having a second condensing heat exchanger which is located directly beneath the first stage and the first condensing heat exchanger for further cooling the flue gas. The flue gas travels in a downward direction only through the housing and exits the housing at the lower end of the housing beneath the second stage. A collection tank is located beneath the second stage of the housing for collecting liquids, condensate, particulate and reaction product.

Abstract: Convection towers which are capable of cleaning the pollution from large quantities of air, of generating electricity, and of producing fresh water utilize the evaporation of water sprayed into the towers to create strong airflows and to remove pollution from the air. Turbines in tunnels at the skirt section of the towers generate electricity, and condensers produce fresh water.

Abstract: A part of the hydrogen sulphide content of a feed gas stream comprising hydrogen sulphide is burned by a burner that fires into a furnace. The combustion is supported by a stream of oxygen or oxygen-enriched air. Resulting sulphur dioxide reacts with residual hydrogen sulphide in the furnace to form sulphur vapor. Sulphur is condensed out of the resulting gas mixture in a sulphur condenser. At least part of the sulphur-free gas mixture flows through a reactor in which its sulphur dioxide content is reduced to hydrogen sulphide. Water vapor is removed from the resulting gas stream in a water condenser. At least part of the gas stream now essentially free of water vapor is recycled to the furnace. A purge stream is taken either from immediately downstream of the sulphur condenser or from intermediate the water condenser and the furnace, or from the furnace and, if desired, subjected to further treatment to remove sulphur-containing gases therefrom.

Abstract: A catalytic vessel for adsorbing catalytic metals, such as from automotive exhaust gases, and carrying out three-way catalysis includes an inlet at an upstream end, a plurality of catalytic chambers located downstream of the inlet, and an outlet. At least one of the catalytic chambers contains a plurality of sheet members preferably made of steel and adapted for deposition of a metal selected from the group of noble and non-noble metals, and more particularly from the group including platinum, rhodium, rhenium, palladium, and gold. The vessel may be used in a catalytic system which contains a liquid source of metal catalysts, such as a solution or a gasoline additive, from which the metal catalysts are added to a combustion system, and the catalytic vessel, which collects the metal catalysts and is a site for three-way catalytic conversion of starting materials such as automotive emissions to final products.

Abstract: Hot gases from a pressurized fluidized bed reactor system are purified. Under superatmospheric pressure conditions hot exhaust gases are passed through a particle separator, forming a flitrate cake on the surface of the separator, and a reducing agent--such as an NO.sub.x reducing agent (like ammonia), is introduced into the exhaust gases just prior to or just after particle separation. The retention time of the introduced reducing agent is enhanced by providing a low gas velocity (e.g. about 1-20 cm/s) during passage of the gas through the filtrate cake while at superatmospheric pressure. Separation takes place within a distinct pressure vessel the interior of which is at a pressure of about 2-100 bar, and-introduction of reducing agent can take place at multiple locations (one associated with each filter element in the pressure vessel), or at one or more locations just prior to passage of clean gas out of the pressure vessel (typically passed to a turbine).

Abstract: A powdery adsorbent is mixed with an exhaust gas containing fine particles and a noxious and malodorous gas component in gas pipelines, adhering the fine particles to the powdery adsorbent and adsorbing the noxious and malodorous gas with the powdery adsorbent. The powdery adsorbent is then fed to dust collectors where the exhaust gas is separated from the powdery adsorbent and is purified. The separated powdery adsorbent comes in contact with a hot blast at a high temperature, or else is indirectly heated in a pipeline and the adsorbed gas is thereby desorbed. Further, a part of or all of the desorbed powdery adsorbent comes in contact with a hot blast at a higher temperature than the above mentioned temperature, or is indirectly heated in a pipeline, and thereby the fine particles adhered to the powdery adsorbent are thermally decomposed. In this way, the powdery adsorbent is regenerated, and can be returned to be mixed with the exhaust gas in order to be reused.

Abstract: A method for cleaning a flue gas containing flyash, sulfur dioxide and other contaminants includes providing a slurry source having a slurry of primarily water, magnesium sulfite and magnesium hydroxide along with small quantities of magnesium sulfate and magnesium chloride. The flyash is first removed from the flue gas and the flue gas is sprayed with the slurry for forming reaction products in the flue gas. The reaction products are then collected from the flue gas and a first portion of the reaction products is provided to the slurry source. A remaining portion of the reaction products is heated for decomposing into sulfur dioxide and magnesium oxide. The magnesium oxide is then provided to the slurry source. Magnesium sulfate and magnesium chloride are purged from the slurry source.

Abstract: A method for injecting an aqueous ammonia into a flue gas for reducing NO.sub.x in the flue gas comprises providing at least one tube pass in a path of the flue gas. As the vaporized aqueous ammonia and air mixture passes through the tube, it is injected into the flue gas. The flue gas raises the temperature of the remaining vaporized aqueous ammonia mixture for later use in vaporization of the aqueous ammonia.

Abstract: An integrated SCR ESP employs catalytic collector plates for NO.sub.x and particulate removal. Ammonia injected either directly in the ESP or upstream therefrom catalytically reduces NO.sub.x to nitrogen and water. The excess ammonia assists in capturing particulates in the ESP. This prevents problems of ammonia slippage. The SCR catalytic collector plates are positioned in at least one field of the ESP and preferably in at least the first field.

Abstract: A multiple bed regenerative incinerator is cycled at regular intervals by an automatic control which causes fuel gas to be added to the impure inlet air for a first part of each cycle interval and interrupts the flow of fuel gas to the impure air inlet during a last part of each cycle interval thereby improving the purging of fuel gas from the regenerator being fed the impure air. Fuel gas flow may be adjusted by the control in response to signals from a monitor sensing the lower explosive limit of the impure air/fuel gas mixture. The control may cause the fuel gas to be delivered to a burner in a combustion chamber interconnecting the hot ends of the regenerators during the last part of each cycle interval. High dilution of fuel limits fume temperature and NOx production.

Abstract: A process and apparatus for generating elemental sulfur and re-usable metal oxide from spent metal-sulfur compound. Spent metal-sulfur compound is regenerated to re-usable metal oxide by moving a bed of spent metal-sulfur compound progressively through a single regeneration vessel having a first and second regeneration stage and a third cooling and purging stage. The regeneration is carried out and elemental sulfur is generated in the first stage by introducing a first gas of sulfur dioxide which contains oxygen at a concentration less than the stoichiometric amount required for complete oxidation of the spent metal-sulfur compound. A second gas containing sulfur dioxide and excess oxygen at a concentration sufficient for complete oxidation of the partially spent metal-sulfur compound, is introduced into the second regeneration stage. Gaseous sulfur formed in the first regeneration stage is removed prior to introducing the second gas into the second regeneration stage.

Abstract: An apparatus for catalytic reduction of a nitrogen oxide in a waste gas includes a regenerative heat exchanger containing a heat-storage material consisting at least partially of a catalytic material, inlet and outlet conduits for supplying the waste gases to the heat exchanger and for delivering purified waste gases from the apparatus, respectively, first and second hoods arranged in inlet and outlet conduits respectively, on opposite sides of the heat storage material, a conduit for conducting a gaseous medium through heat exchanger, the gaseous medium flowing, in heat exchanger, through first and second hoods, and a conduit for supplying a reducing agent into the heat exchange for assisting in the catalytic reduction of the nitrogen oxide in the waste gases by the heat-storage material.

Abstract: A catalytic converter for accelerating at least one reaction between at least two reactants of a gas mixture includes a catalyst carrier, and a catalytically active substance. The catalytically active substance has a varable chemical composition which is varied along a flow direction of a gas mixture, for suppressing undesired side reactions.

Abstract: An engine exhaust gas cleaning system including a converter section that is disposed at the rear end of the exhaust pipe and which has an outer shell that is surrounded by a further outer shell having a rearwardly disposed atmospheric air inlet and a forwardly disposed atmospheric air outlet that communicates with the inlet of the converter through a venturi section. This heats the air admitted to the converter and also insures that any exhaust sound or exhaust leakage will be disposed rearwardly.

Abstract: A stream of air containing oxidizable pollutants is passed in an air-conditioning system through a conditioning station, an ozonating station, a filter station downstream of the ozonating station, and a testing station downstream of the filter station and then introduced into a living space. Ozone is added to the stream in the ozone station to oxidize the pollutants in the stream. The added ozone is decomposed into stable oxygen in the filter station and the ozone concentration in the stream is detected at the testing station with a sensor and the system is at least partially shut down when the detected ozone concentration exceeds a predetermined safety threshold. The concentration of pollutants in the stream is detected upstream of the ozonating station and the amount of ozone added to the stream in the ozonating station is adjusted so that it just corresponds to the amount needed to oxidize the pollutants sensed and does not substantially exceed this amount.

Abstract: An apparatus for the thermal destruction of waste which includes an afterburner assembly for removing pollutants from industrial waste streams by high temperature thermal destruction using a mixture of gas and gaseous hydrocarbons which is injected into the combustion chamber of the assembly using a ring injector assembly of novel construction.

Abstract: This invention relates to the catalytic reduction of nitrogen monoxide (NO) from highly oxidizing environments. Such catalytic reductions of this type employ the use of small quantities of methane (CH.sub.4) to provide a selective catalytic reduction (SCR) of the NO.

Abstract: A system and method of converting flue gas pollutants to marketable byproducts of ammonium bisulfite and ammonium bisulfate, which are collected, and to other harmless byproducts which may be safely discharged is provided. The system removes as much particulate material and reaction inhibiting coal tar components as possible via an electrostatic precipitator and then passes the flue gas through a heat exchanger, wherein it is cooled by boiler feedwater. A suds producing detergent is introduced to the flue gas in order to separate any remaining coal tar components from the condensing moisture. Due to the removal of the tar components, sulfur dioxide and nitrous oxide readily dissolve in the condensing moisture when sufficiently cooled.

Abstract: The present invention provides a wet-processing apparatus comprising a chamber having a working space, means for wet processing in the working space, means for supplying nitrogen gas in fluid communication with the chamber, a nitrogen gas outlet located in a wall of the chamber, means for cleaning nitrogen gas by removing contaminants mixed therewith located in an area of the chamber downstream of the working space and upstream of the nitrogen gas outlet and having a contaminated gas inlet and a treated gas outlet in fluid communication with the chamber, means for diverting gas in the chamber located downstream of the treated gas outlet and upstream of the nitrogen gas supplying means, the means for diverting gas having a first position providing egress of treated gas from the chamber through the nitrogen gas outlet while inhibiting fluid communication to other parts of the chamber and a second position permitting fluid communication and recirculation of the treated gas to other parts of the chamber while pre

Abstract: An apparatus to produce a low oxygen containing gas in which exhaust gases from an engine are cooled by passing them through a manifold cooler. Harmful gases are removed by passing the exhaust gases through a catalytic converter for removal of NOX. Air in injected and the exhaust gas passed through a further catalytic converter for removal of CO. The exhaust gases are then cooled by passing them through an air to gas heat exchanger, and a series of water-cooled heat exchangers which are water-cooled and the resulting condensate removed by condensate drain. The water coolant is supplied by a closed circuit radiator system. The exhaust gases are then passed through a condensate screen and two filter beds for removal of moisture which may be regenerated by passing warm air derived from the air to gas heat exchanger through them when not in use. The operation of the system may be regulated by a fuel management system which includes an oxygen sensor.

Abstract: The present invention relates, in general, to apparatus for providing uniform fluid flow in vessels having packing materials or particulates and, in particular, to apparatus for providing uniform gas flow in pressure swing adsorbent vessels.

Abstract: A feed gas stream containing at least 60% by volume of hydrogen sulphide is burnt in a first combustion region to form water vapor and sulphur dioxide. Oxygen is employed to support combustion is the region. Thermal reaction then takes place in a thermal reaction region between hydrogen sulphide and sulphur dioxide to form sulphur vapor and water vapor. The resulting gas mixture is then cooled and sulphur vapor is extracted in a condenser. The gas mixture then passes into a second combustion region in which a further portion of the hydrogen sulphide is burnt in the presence of oxygen to form further sulphur dioxide and to adjust the mole ratio of hydrogen sulphide to sulphur dioxide to about 2:1. Further reaction between hydrogen sulphide and sulphur dioxide may be conducted in a further thermal reaction region and in catalytic reactors with further sulphur extraction in further condensers.