Plural Chemical Reaction Stages Patents (Class 422/170)
  • Patent number: 5795548
    Abstract: A combined furnace limestone injection and dry scrubber flue gas desulfurization (FGD) system collects solids from the flue gas stream in first particulate collection device located downstream of an outlet of a convection pass of the furnace and upstream of the dry scrubber. The collected solids are diverted to the dry scrubber feed slurry preparation system to increase sulfur oxide species removal efficiency and sorbent utilization. The level of lime in the feed slurry provided to the dry scrubber is thus increased, which enhances removal of sulfur oxide species in the dry scrubber. The decreased particulate loading to the dry scrubber helps maintain a desired degree of free moisture in the flue gas stream entering the dry scrubber, which enhances sulfur oxide species removal both in the dry scrubber and downstream particulate collector, normally a baghouse.
    Type: Grant
    Filed: March 8, 1996
    Date of Patent: August 18, 1998
    Assignee: McDermott Technology, Inc.
    Inventors: Deborah A. Madden, George A. Farthing
  • Patent number: 5776417
    Abstract: Substantial improvements in the control of pollutants from internal combustion engines may be obtained by pre-drying a catalyst/hydrocarbon trap system and preferably incorporating a water trap in a catalyst/hydrocarbon trap system. A pre-drying system dries the water trap, HC trap and catalyst, eg upon engine switch-off.
    Type: Grant
    Filed: June 6, 1996
    Date of Patent: July 7, 1998
    Assignee: Johnson Matthey Public Limited Company
    Inventors: Johnathan C. Frost, Stephen C. Bennett, David S. Lafyatis, Andrew P. Walker
  • Patent number: 5768888
    Abstract: A purification system and a method for controlling exhaust gas emissions from internal combustion engines during start-up and restart, as well as during normal engine operation is disclosed. A method for controlling emissions during low load operation of a diesel engine fueled with a diesel fuel/methane mixture is also provided. Exhaust gases are contacted with a gas permeable solid material containing an adsorbent and a catalyst capable of converting the noxious components into innocuous materials. The flow of the gases through the gas permeable solid material is reversed in a series of continuing cycles to bring or to maintain the catalyst in a temperature range suitable for controlling the noxious components, below which temperature the noxious materials are adsorbed by the adsorbent.
    Type: Grant
    Filed: November 8, 1996
    Date of Patent: June 23, 1998
    Assignee: Matros Technologies, Inc.
    Inventors: Yurii Sh. Matros, Grigorii A. Bunimovich, Vadim O. Strots
  • Patent number: 5770163
    Abstract: For a system having a source of nitrogen oxide-containing gas, an ammonia reduction denitrator, and a leak ammonia recovery unit which adsorbs and removes ammonia escaping from said ammonia reduction denitrator, a method of removing adsorbed ammonia from said leak ammonia recovery unit and reusing the removed ammonia is provided which includes the steps of: introducing hot exhaust gas discharged from said nitrogen oxide-containing gas source into said leak ammonia recovery unit to desorb ammonia therefrom; after desorption of ammonia, cooling said heated leak ammonia recovery unit with cool air; and feeding ammonia carried away by said hot exhaust gas and said cool air to an upstream side of said ammonia reduction denitrator or to the source of nitrogen oxide-containing gas.
    Type: Grant
    Filed: April 26, 1996
    Date of Patent: June 23, 1998
    Assignee: Mitsubishi Jukogyo Kabushiki Kaisha
    Inventors: Tadashi Gengo, Norihisa Kobayashi, Koichi Sakamoto
  • Patent number: 5766559
    Abstract: An exhaust gas management apparatus including: an air flow directing body forming a bypass passage including an inlet end and an outlet end and defining a low pressure region between the inlet end and the outlet end having a first diameter less than second and third diameters of the inlet and outlet ends, respectively; a hydrocarbon adsorber mounted radially exterior of the air flow directing body; an air source located downstream in an exhaust flow path of the low pressure region of the air flow body; and an air pump forcing air through the air source wherein, during activation of the pump, the bypass passage is valved shut at the low pressure region, wherein less air is required to valve shut the bypass passage than would be required at another location within the bypass passage.
    Type: Grant
    Filed: February 3, 1997
    Date of Patent: June 16, 1998
    Assignee: General Motors Corporation
    Inventors: Scott Christopher Blanchet, Wayne Richard Moore
  • Patent number: 5762883
    Abstract: This invention relates to a wet flue gas desulfurization apparatus including: an absorption tower having defined in the lower part thereof a tank for holding a calcium compound-containing slurry fed thereto; a circulating pump for delivering the slurry within the tank to the upper part of the absorption tower in order to bring it into contact with flue gas; air supply member for supplying air to the tank for purposes of oxidation; a withdrawal pump for withdrawing the slurry within the tank in order to recover gypsum formed as a by-product or discharge waste water; falling slurry withdrawal member for withdrawing part of the slurry delivered to the upper part of the absorption tower by the circulating pump and falling through the absorption tower at a position above the liquid surface of the tank; and mixing member for the slurry withdrawn by the falling slurry withdrawal member with the slurry withdrawn from the tank by the withdrawal pump, whereby oxidizing substances produced in the tank of the absorption
    Type: Grant
    Filed: June 19, 1996
    Date of Patent: June 9, 1998
    Assignee: Mitsubishi Jukogyo Kabushiki Kaisha
    Inventors: Kiyoshi Okazoe, Eiji Ochi, Toru Takashina, Susumu Okino
  • Patent number: 5738833
    Abstract: A support is composed of a plurality of units which each consist of a hollow essentially cylindrical member in which a sets of parallel non-intersecting wires are strung. The units are arranged one after the other with the wires extending either parallel to each other or at different angles to one another. The cylindrical members are in some embodiments formed with crenelations over which wire wound during the stringing process. Alternatively, through-holes are used to receive portions of the wires.
    Type: Grant
    Filed: February 13, 1996
    Date of Patent: April 14, 1998
    Assignee: Usui Kokusai Sangyo Kaisha, Ltd.
    Inventor: Masayoshi Usui
  • Patent number: 5725774
    Abstract: The present invention relates to a method and to a device for separating plasma from whole blood. The method and device utilize a permeable non-glass fiber matrix containing a polyol which is capable of clumping red blood cells. The matrix, in the absence of such a polyol, would otherwise be porous to red blood cells. The polyol-containing matrix has a first surface and a second surface such that a whole blood sample which is applied to the first surface flows directionally toward the second surface. Plasma separated from whole blood becomes available at the second surface of the matrix and can be tested for the presence of a particular analyte, such as glucose or fructosamine, as provided by multi-layer test devices of the present invention.
    Type: Grant
    Filed: April 7, 1995
    Date of Patent: March 10, 1998
    Assignee: LXN Corp.
    Inventor: Gebhard Neyer
  • Patent number: 5718873
    Abstract: An apparatus (50) for contacting a gas stream (62) with solid particulate material includes two contacting zones (58, 60). Sets of angled blades (54, 56) cause gas flowing through the contacting zones (58, 60) to have a swirling circumferential velocity. Solid particulate material is fed from hopper (70) via line (72) to the upper contacting zone (56), in which the swirling gas flow causes a turbulent band of particles (60) to form. Contact between the gas and the solid occurs in this band of particles. Overflow of particles from band (74) flows down conduits (76, 77) and into lower contacting zone (58). The swirling gas flow in contacting zone (58) causes a turbulent band of particles (78) to be established. The gas stream enters at conduit (62) and travels through the turbulent band of particles (78) in the lower contacting zone (58). The gas then passes through restriction (66), through the turbulent band of particles (74) in upper contacting zone (60) and then leaves the apparatus (50) via outlet (68).
    Type: Grant
    Filed: October 1, 1996
    Date of Patent: February 17, 1998
    Assignee: Comalco Aluminium Limited
    Inventors: Grant A. Wellwood, Martin A. Groszek, Matthew Ion Liddy
  • Patent number: 5688474
    Abstract: A method of microfabricating a matrix of evenly distributed catalytic articles, with the matrix then being used to treat reactants in a stream of gases. The matrix is created by depositing areas of conductive material on a nonconductive base wafer or substrate, and then depositing catalyst particles in electrical communication with the conductive material so that a series of localized electrical fields can be created upon the introduction of a power source. A dielectric material surrounding the catalyst particles can be altered by increasing the applied voltage, thereby increasing the strength of the electrical field. A device so constructed is placed in a stream of gases, and the localized electrical fields alter the selectivity and the reactivity of the reactants in the stream of gases.
    Type: Grant
    Filed: January 27, 1995
    Date of Patent: November 18, 1997
    Assignee: Eduardo E. Wolf
    Inventor: Eduardo E. Wolf
  • Patent number: 5681533
    Abstract: An environment decontaminating system has an air cleaning and deodorizing function. It includes a housing having an inlet and an outlet for passage of air. A DC high voltage dust collector and a dust catching filter are provided adjacent the inlet. An ozone generator is positioned adjacent the filter. An odor/ozone turbulent mixing plate is positioned adjacent the ozone generator. A deodorizing catalyst is positioned adjacent the mixing plate. An acid gas absorbent, a suction scavaging fan, and an ozone concentration sensor are positioned adjacent an outlet of the housing.
    Type: Grant
    Filed: October 30, 1995
    Date of Patent: October 28, 1997
    Assignee: Yushin Engineering
    Inventor: Tsutomu Hiromi
  • Patent number: 5676913
    Abstract: A vehicle, preferably a public transport vehicle, transports an apparatus providing for intake of polluted air, which is purified of carbon, nitrogen and sulphur oxides, unburned matter and particulate, the impurities being collected and disposed of after a working cycle of around 10 hours. The energy consumption is negligible when compared with the volume of air treated. (FIG. 2).
    Type: Grant
    Filed: July 7, 1995
    Date of Patent: October 14, 1997
    Assignee: BCP S.r.l.
    Inventors: Francesco Cirillo, Remo Pimpinelli
  • Patent number: 5674459
    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.
    Type: Grant
    Filed: May 15, 1996
    Date of Patent: October 7, 1997
    Assignee: The Babcock & Wilcox Company
    Inventors: Wadie F. Gohara, Dennis W. Johnson
  • Patent number: 5663476
    Abstract: An apparatus for and method of decomposing a chemical compound, which may be an environmentally undesirable material, is accomplished by impinging a flow of the chemical compound on a heated member. Various embodiments are possible, including having the member have a plurality of openings, having the member be configured to direct the flow of the chemical compound in a particular direction, and having the member be self supported on the wall of the reaction chamber.
    Type: Grant
    Filed: April 29, 1994
    Date of Patent: September 2, 1997
    Assignee: Motorola, Inc.
    Inventors: Jerry D. Cripe, Gerard T. Reed, James C. Koontz
  • Patent number: 5648050
    Abstract: It is the primary object of the present invention to provide a catalyst converter which can hold a sufficient amount of catalyst to raise the temperature thereof to the catalyst activation temperature in a short time without enlarging the metal carrier itself. The metal carrier 1 is arranged in the course of an exhaust manifold 3 of an engine 2 and is composed of an alternating winding of a flat sheet 7 and a corrugated sheet 8, wherein slit parts 9 are formed in the flat sheet 7 and the corrugated sheet 8 of the metal carrier 1 in an end portion thereof, on the side the engine 2.
    Type: Grant
    Filed: March 16, 1994
    Date of Patent: July 15, 1997
    Assignee: Nippondenso Co., Ltd.
    Inventors: Toshiki Matsumoto, Tetsuya Toyao, Tetsuya Nakamura, Shigeru Maehara, Hiromasa Aoki, Tatsuya Fujita, Senta Tojo, Kinji Hodaira, Takeshi Matsui, Yushi Fukuda
  • Patent number: 5648049
    Abstract: A purging electrostatic gun for uniformly and essentially completely electrostatically charging the outer surfaces of a flow of sorbent material particles passed therethrough under pressure that are then injected into a polluted gas stream for contacting to electrostatically attract and react to pollutant particles and pollutant gases in that gas stream that are then removed in a conventional pollution control filtration device. The purging electrostatic gun includes a housing wherein a charging electrode is maintained that is electrically coupled to receive a high voltage and is axially centered in a cylindrical barrel charging section wherethrough a laminar flow of sorbent material is directed. The charging electrode has a forward portion that extends beyond a barrel charging section forward end and is immediately opposite to a surface of a grounding ring or collar. The grounding ring or collar is maintained in the housing and is connected to earth ground.
    Type: Grant
    Filed: November 29, 1995
    Date of Patent: July 15, 1997
    Assignee: Alanco Environmental Resources Corp.
    Inventors: James T. Jones, Larry Kersey, Michael Walters
  • Patent number: 5645802
    Abstract: A method and apparatus for the treatment of a waste gas containing dust and chemical contaminants are disclosed. The apparatus includes a combination of a cooling/dust-eliminating chamber and a chemical treatment chamber in a single container. The first mentioned chamber is provided with sprayers for the cooling liquid, a perpendicular bulkhead or pipes, a collecting plate for the cooling liquid and gas-dispersing pipes in a special configuration, so that the dust-liquid separation can be efficiently effected without badly affecting the chemical treatment of the gas. Thus, the apparatus can be minimized in size as a whole and made economically attractive.
    Type: Grant
    Filed: December 4, 1991
    Date of Patent: July 8, 1997
    Assignee: Chiyoda Corporation
    Inventors: Hiroshi Yanagioka, Yoshio Ogawa, Yoshiaki Komatsubara, Kenji Kobayashi
  • Patent number: 5624648
    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.
    Type: Grant
    Filed: October 11, 1995
    Date of Patent: April 29, 1997
    Assignee: ABB Flakt AB
    Inventor: Kurt Carlsson
  • Patent number: 5620668
    Abstract: A regenerative thermal oxidizer in which contaminated air is first passed through a hot heat-exchange bed and into a communicating high temperature oxidation (combustion) chamber, and then through a relatively cool second heat exchange bed. The apparatus includes a number of internally insulated, ceramic filled heat recovery columns topped by an internally insulated combustion chamber. Process air is directed into heat exchange media in one of said columns via an annular distribution system, which allows for the uniform flow of gas in the apparatus, and greatly reduces the flushing volume. Oxidation is completed as the flow passes through the combustion chamber, where one or more burners are located. From the combustion chamber, the air flows vertically downward through another column containing heat exchange media, thereby storing heat in the media for use in a subsequent inlet cycle when the flow control valves reverse.
    Type: Grant
    Filed: February 6, 1996
    Date of Patent: April 15, 1997
    Assignee: W.R. Grace & Co.-Conn.
    Inventors: Thomas D. Driscoll, James T. Gallo, Michael P. Loos, David L. Petersen
  • Patent number: 5614156
    Abstract: A thermoelectric reactor for the chemical destruction of heavy-molecule volatile organic compounds (VOCs), semi-volatile organic compounds, or hydrogen sulfide contained in a gaseous feed. The reactor contains a hollow core containing energy sources. This reactor core surrounded by several ceramic walls and insulating zones. Uniform, high temperatures, up to at least 1900.degree. C., are obtained in the reactor core not only from direct radiant heat from the energy sources, but also from energy reflected and emitted from the surrounding zones. Reaction rates are enhanced by non-equilibrium conditions caused by electromagnetic threes derived from the energy sources. Further chemical destruction is accomplished in a porous energy retaining zone after passage through the reactor core. Ionizing gases and ionization seed material may be added to the gaseous feed material to increase electric conductivity and promote dissociation and ionization in the reactor core.
    Type: Grant
    Filed: February 13, 1996
    Date of Patent: March 25, 1997
    Inventor: Chi S. Wang
  • Patent number: 5612005
    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.
    Type: Grant
    Filed: May 23, 1995
    Date of Patent: March 18, 1997
    Assignee: Salem Engelhard
    Inventor: Richard Garvey
  • Patent number: 5611198
    Abstract: The present invention is particularly applicable to lean burn engines that produce exhaust containing insufficient amounts of unburned hydrocarbons to satisfactorily reduce NOx emissions without undermining engine performance. In the exhaust purification system, ethanol or another suitable hydrocarbon is injected into the exhaust stream at an appropriate location between the engine and the catalytic converter. A deNOx catalytic converter is positioned within the exhaust downstream from the ethanol injection point. The combination engine application, ethanol injection and suitable deNOx catalyst combine to reduce NOx to satisfactory levels without producing significant amounts of undesirable secondary nitrogen containing compounds. An oxidation catalytic converter is positioned in the exhaust downstream from the deNOx catalytic converter. The oxidation catalyst serves to convert any remaining unburned hydrocarbons into carbon dioxide and water.
    Type: Grant
    Filed: August 16, 1994
    Date of Patent: March 18, 1997
    Assignee: Caterpillar Inc.
    Inventors: William H. Lane, Daniel J. Learned, Randy N. Peterson, Aaron L. Smith, Scott T. White
  • Patent number: 5609841
    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.
    Type: Grant
    Filed: October 19, 1995
    Date of Patent: March 11, 1997
    Assignee: Hoogovens Staal, B.V.
    Inventors: Johannes Greefkes, Adrianus J. den Hartog
  • Patent number: 5601790
    Abstract: Methods and apparatus are provided for destruction of volatile organic compounds ("VOC's") from process fumes having variable amounts of such VOC's wherein a nominal amount of the fumes are passed through an oxidizer for destruction of the VOC's and the hot products from the oxidizer are fed to an afterburner that is principally made up of a matrix bed of heat resistant material. The heat from the oxidized gases heats the matrix bed. Fume flows exceeding the nominal flow are bypassed directly to an inlet port of the afterburner where they are passed through the matrix bed of the afterburner, which has been heated by the oxidized gases from the oxidizer, and are combusted into additional gaseous products in a combustion wave. The system allows for utilization of the heat produced from the oxidation of the nominal flow for destructing fume flows that exceed the nominal flow.
    Type: Grant
    Filed: April 21, 1995
    Date of Patent: February 11, 1997
    Assignee: Thermatrix, Inc.
    Inventors: John D. Stilger, Richard J. Martin, Mark R. Holst, Samson C. Yee
  • Patent number: 5601792
    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.
    Type: Grant
    Filed: April 10, 1995
    Date of Patent: February 11, 1997
    Inventors: Hans T. Hug, Axel Hartenstein, Michael Hug
  • Patent number: 5599508
    Abstract: A method and apparatus is described for removing acid gases, air toxics and/or other contaminants from a flue gas stream formed during the combustion of fossil fuel, and/or waste materials. The flue gas stream is conditioned immediately downstream of the combustion source with a finely atomized liquid which is preferably water. The water spray decreases the volume of the flue gas and cools the flue gas to condense air toxics or heavy metals on the baghouse fabric filters. Advantageously, this may utilize the alkalinity inherent in the fly ash component of the particulate to assist in the removal of acid gases and/or other contaminants via adsorption. Also, the conditioned gas reduces the flue gas volumetric flow rate and hence the size of the particulate collection device, and the cost of the fabric filter media.
    Type: Grant
    Filed: November 22, 1994
    Date of Patent: February 4, 1997
    Assignee: The Babcock & Wilcox Company
    Inventors: Robert Martinelli, Dennis W. Johnson, Robert B. Myers, Fred C. Owens, II, Peter V. Smith
  • Patent number: 5595713
    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.
    Type: Grant
    Filed: September 8, 1994
    Date of Patent: January 21, 1997
    Assignee: The Babcock & Wilcox Company
    Inventors: Wadie F. Gohara, Dennis W. Johnson
  • Patent number: 5591412
    Abstract: An electrostatic gun for electrostatically charging and injecting sorbent particles into a flue gas stream to contact, and electrostatically charge, pollution particles in that flue gas stream. The electrostatic gun is for inclusion as a component of an apparatus for the remediation of pollution particles from a flue gas stream whereafter the clean gas flow is vented to atmosphere. The electrostatic gun receives laminar flow of a selected sorbent material and charges, either positively or negatively, the surface of each sorbent particle in that flow. To provide electrostatic charging to the individual particles, the flow is directed through a straight barrel of a housing of the electrostatic gun to pass alongside a charging wand that is centered axially in the straight barrel. The charging wand is connected to receive a voltage from a high voltage power supply to produce a corona discharge wherethrough the sorbent materials pass to electrostatically charge each sorbent particle.
    Type: Grant
    Filed: April 26, 1995
    Date of Patent: January 7, 1997
    Assignee: Alanco Environmental Resources Corp.
    Inventors: James T. Jones, Larry M. Kersey, Richard A. Steinke
  • Patent number: 5575984
    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.
    Type: Grant
    Filed: December 6, 1994
    Date of Patent: November 19, 1996
    Assignee: ABB Environmental Systems, Div. of ABB Flakt, Inc.
    Inventor: Gerald E. Bresowar
  • Patent number: 5569436
    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.
    Type: Grant
    Filed: March 20, 1995
    Date of Patent: October 29, 1996
    Assignee: Beco Engineering Company
    Inventor: Bernard J. Lerner
  • Patent number: 5556604
    Abstract: A method, and an apparatus for carrying out the method, for purifying exhaust gases from internal combustion engines is provided. The engines having a catalyzer system which includes a first catalyzer and at least one second catalyzer, arranged downstream of the first catalyzer, for the conversion of HC, CO and NO.sub.x exhaust gas constituents. Exhaust gases flow through both catalyzers during the entire operating period of the engine. The first catalyzer is suitable for at least the catalytic conversion of HC and CO exhaust gas constituents. In a first step of the method, the first catalyzer is operated over-stoichiometrically during the cold starting phase in order to reduce the HC and CO emissions and, in a second step of the method with .lambda.-controlled stoichiometric exhaust gas composition, the catalytic conversion of the exhaust gas is at least largely de-activated and in the first catalyzer takes place in the second catalyzer.
    Type: Grant
    Filed: March 1, 1995
    Date of Patent: September 17, 1996
    Assignee: Mercedes-Benz AG
    Inventors: Wolfgang Zahn, Gunter Loose, Axel Hirschmann
  • Patent number: 5540895
    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.
    Type: Grant
    Filed: December 7, 1994
    Date of Patent: July 30, 1996
    Assignee: Paul Wurth S.A.
    Inventors: Ernest Faber, Romain Frieden, Marc Solvi, Louis Schmit, Leon Ulveling
  • Patent number: 5525308
    Abstract: An exhaust gas purifier arrangement for an internal combustion engine includes a gas adsorber and a catalyzer located downstream from the adsorber in the direction of exhaust gas flow and a burner providing hot burner gases to heat the catalyzer through a burner pipe which traverses the adsorber, and also includes an arrangement for controlling the heat transfer between the burner pipe and the gas adsorber so that heating the adsorber to its desorption temperature is accelerated at low ambient temperatures.
    Type: Grant
    Filed: February 10, 1995
    Date of Patent: June 11, 1996
    Assignee: Volkswagen AG
    Inventor: Polat Oser
  • Patent number: 5510086
    Abstract: The invention relates to a catalytic converter system for controlling exhaust emissions from a combustion engine wherein the catalytic converter has three catalysts zones. A zone which is first in line with the direction of the flow of exhaust and which includes a light-off catalyst such as palladium. A second zone in line of the direction of the exhaust flow includes a hydrocarbon adsorber/catalyst. A third zone in line of the direction of the exhaust flow includes a catalyst system converter CO and NO.sub.x. The three-zone system of the present invention produces hydrocarbon efficiencies above 98 percent and retains hydrocarbon efficiencies above 50 percent in cold performance situations immediately after start-up of the combustion engine.
    Type: Grant
    Filed: April 10, 1995
    Date of Patent: April 23, 1996
    Assignee: General Motors Corporation
    Inventors: Mark D. Hemingway, George A. English
  • Patent number: 5505909
    Abstract: The invention relates to a process and a device for detoxifying the waste gases from waste incinerating plants, at least one plasma gas flow being admixed to the hot fresh flue gas flow from the waste incinerating plant for the thermal decomposition of the toxic compounds, the fresh flue gas flow is preferably heated up in a recuperation stage with a high-temperature heat exchanger by the plasma-beam-treated flue gas in the counter-flow principle and subsequently at least one plasma gas flow is mixed into the fresh flue gas heated in this fashion. Following this, the gas mixture being at a peak temperature is used for heating up the fresh flue gas flow in the recuperation stage and cooled to a temperature which is still above the waste gas temperature, and it is subsequently finally treated in a waste heat system and a flue gas purification.
    Type: Grant
    Filed: May 16, 1994
    Date of Patent: April 9, 1996
    Assignee: Maschinen-und Anlagenbau Grimma GmbH
    Inventors: Hans-Ulrich Dummersdorf, Heinz Dummersdorf
  • Patent number: 5492676
    Abstract: A denitrification system comprises an electrostatic precipitator (3) in the foremost stage of the system inlet, an ozone supply nozzle (4) for an ozonizer (5) for generating ozone required for oxidizing the NO into NO.sub.2, followed by a fan or an agitator (6), and an NO.sub.2 absorbent filter (7) in the final stage arranged in that order. Further, this system may comprise the control of feeding back the residual O.sub.3 concentration after oxidation, to achieve the higher denitrification rate.
    Type: Grant
    Filed: May 27, 1994
    Date of Patent: February 20, 1996
    Assignees: Matsushita Electric Industrial Co., Ltd., Matsushita Seiko Co., Ltd.
    Inventors: Atsushi Katatani, Akira Hashimoto
  • Patent number: 5480619
    Abstract: A combined regenerative scrubber and condensing heat exchanger system comprises a housing having an inlet and an outlet for channeling flue gas into and out of the housing. A first heat exchanger is located in the housing for contacting a downward flow of the flue gas for providing an initial cooling of the flue gas. The flue gas is channeled through a second heat exchanger in an upward direction for providing a further cooling of the flue gas. A reagent scrubbing spray device is used to spray reagent into the flue gas as well as onto the second heat exchanger for removing SO.sub.2 from the flue gas and for cleaning the second heat exchanger. A regeneration device is used to regenerate reagent from the reaction product as well as to recover SO.sub.2 from the reaction product.
    Type: Grant
    Filed: June 28, 1994
    Date of Patent: January 2, 1996
    Assignee: The Babcock & Wilcox Company
    Inventors: Dennis W. Johnson, Pervaje A. Bhat
  • Patent number: 5478530
    Abstract: An HMA plant has a catalytic reactor which can effectively and reliably reduce VOC and NO.sub.x emissions produced during plant operation. The reactor effectiveness is enhanced by exhausting the gas stream from a primary dryer of the plant at a sufficiently high temperature for effective catalytic reaction. Since withdrawal of gases from the dryer at these elevated temperatures necessarily reduces the effectiveness of the dryer, overall plant efficiency is maintained by using the treated gas stream from the catalytic reactor to heat further the aggregate in a secondary dryer, which is preferably a finishing dryer/mixer such as a fixed sleeve dryer drum coater. Poisoning of the catalyst is avoided by removing at least a large portion of the dust in the gas stream via a high efficiency cyclone prior to introducing the gas stream into the catalytic reactor. Ammonia or urea may if desired also be injected into the gas stream prior to its introduction into the catalytic reactor.
    Type: Grant
    Filed: September 22, 1994
    Date of Patent: December 26, 1995
    Assignee: Astec Industries, Inc.
    Inventor: Malcolm L. Swanson
  • Patent number: 5472673
    Abstract: An engine comprising an exhaust passage having therein a NO.sub.x absorbent which absorbs the NO.sub.x when the air-fuel ratio of the exhaust gas flowing into the NO.sub.x absorbent is lean and releases the absorbed NO.sub.x when the air-fuel ratio of the exhaust gas flowing into the NO.sub.x absorbent becomes the stoichiometric air-fuel ratio or rich. A sulphur trapping device for trapping SO.sub.x contained in the exhaust gas is arranged in the exhaust passage upstream of the NO.sub.x absorbent.
    Type: Grant
    Filed: November 14, 1994
    Date of Patent: December 5, 1995
    Assignee: Toyota Jidosha Kabushiki Kaisha
    Inventors: Masato Goto, Satoshi Iguchi, Kenji Katoh, Tetsuro Kihara
  • Patent number: 5462718
    Abstract: A system and method are disclosed for lowering NO.sub.x levels in flue gases of a fluidized bed reactor using selective non-catalytic reduction. A reactor is connected to a separator by a duct, and a reactant is introduced into the duct for decreasing NO.sub.x levels in the flue gases passing from the reactor, through the duct, and into the separator. The reactant, such as ammonia or urea, is selectively injected into a gaseous-rich region of the duct, near an upper, inner portion of the duct, so that a high degree of mixing of the reactant with flue gases is achieved while maintaining a low degree of mixing of the reactant with the particulate materials. The point of injection of the reactant into the duct is also at a location nearer to the reactor than to the separator to provide for increased residence time. In this manner, the reactant is used efficiently while obtaining the desired lowering of NO.sub.x levels in the flue gases.
    Type: Grant
    Filed: June 13, 1994
    Date of Patent: October 31, 1995
    Assignee: Foster Wheeler Energy Corporation
    Inventor: Igbal F. Abdulally
  • Patent number: 5458862
    Abstract: A process for purifying exhaust gases, especially from vacuum pyrolysis installations by means of the extraction of the exhaust gases and their combustion with a supply of air. Immediately after their formation, the exhaust gases are subjected to complete combustion with a controlled air supply and an under pressure of 0.5 to 0.95 bar (500 to 50 mbar absolute) generated by a vacuum pump, whereupon the gaseous reaction products are cooled to 10.degree. to 25.degree. C. to prevent damage to the vacuum pump and then the cooled gaseous reaction products are extracted by the vacuum pump.
    Type: Grant
    Filed: June 6, 1994
    Date of Patent: October 17, 1995
    Assignee: Rieter Automatik GmbH
    Inventor: Erwin Glawion
  • Patent number: 5455012
    Abstract: In an exhaust gas purifying apparatus including first and second exhaust converters composed of a honeycomb catalytic substrate, arranged in sequence from an exhaust manifold downstream along exhaust gas flow of an engine, wherein the catalytic substrate of the first converter has a heat capacity of not exceeding 0.5 J/K per 1 cm.sup.3 in temperatures ranging from room temperature up to 300.degree. C., and the catalytic substrate of the second converter has a geometric surface area of at least 25 cm.sup.2 /cm.sup.3. The first converter purifies exhaust gas immediately after starting up and before completion of warming up of the engine, and the second converter further purifies noxious contents still remaining as being beyond capacity of the first converter.
    Type: Grant
    Filed: March 24, 1994
    Date of Patent: October 3, 1995
    Assignee: NGK Insulators, Ltd.
    Inventors: Minoru Machida, Toshio Yamada
  • Patent number: 5439659
    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.
    Type: Grant
    Filed: May 5, 1993
    Date of Patent: August 8, 1995
    Assignee: Daikin Industries, Ltd.
    Inventor: Masanori Izumo
  • Patent number: 5422081
    Abstract: A double cylinder shaped multilayer structural member comprising ring shaped thin plate small diameter discs and large diameter discs respectively layered via spacers is disposed in the enclosure vessel of a trap device for a vapor phase reaction apparatus. Gas from the intake opening section of the enclosure vessel is introduced into the outer side space of the multilayer structural member of the enclosure vessel, passes through the spaces between the large diameter discs and also passes through the spaces between the small diameter discs, then exits via the inner side space of the multilayer structural member from the outlet opening section of enclosure vessel to the system exterior. As a result of this construction, in comparison to conventional devices, the collection efficiency of reactive components can be increased, the equipment life extended, and maintenance frequency reduced, thereby providing a trap device for a vapor phase reaction apparatus capable of improving productivity.
    Type: Grant
    Filed: November 23, 1993
    Date of Patent: June 6, 1995
    Assignees: Tokyo Electron Kabushiki Kaisha, Tokyo Electron Tohoku Kabushiki Kaisha, Cuno K.K.
    Inventors: Katsushin Miyagi, Osamu Yokokawa, Yoshitaka Okada, Ichiro Nagasaki, Akira Hashimoto
  • Patent number: 5409684
    Abstract: Process and apparatus for the combined production of ammonia synthesis gas and pure hydrogen. There is withdrawn (at 21) a flow of synthesis gas which is first treated in a permeation unit (24) with the return (at 28) of the non-permeated gas, while the permeate (32)is treated by adsorption (34) (35) (36), which permits producing (in 57) very pure hydrogen. The process has a high energy efficiency.
    Type: Grant
    Filed: June 7, 1993
    Date of Patent: April 25, 1995
    Assignee: L'Air Liquide, Societe Anonyme pour l'Etude et l'Exploitation des Procedes Georges Claude
    Inventor: Francois Fuentes
  • Patent number: 5407646
    Abstract: Hydrogen sulfide or other gaseous component is removed from a gas stream containing the same by distribution of the gas stream in the form of fine bubbles by a rotary impeller and stationary shroud arrangement at a submerged location in an aqueous iron or other transition metal chelate solution, or other suitable catalyst, contained in an enclosed reaction vessel. Sulfur particles, or other insoluble phase product, of narrow particle size range formed in the reaction are floated off from the iron chelate solution. An oxygen-containing gas stream also is distributed in the form of fine bubbles by a separate rotary impeller and stationary shroud arrangement at a separate submerged location in the iron chelate solution. The second submerged location generally is separated from the first by a baffle extending downwardly in the reaction vessel from a top closure towards a bottom closure.
    Type: Grant
    Filed: April 19, 1993
    Date of Patent: April 18, 1995
    Assignee: The University of Toronto Innovations Foundation
    Inventors: James W. Smith, Nim Y. Lee
  • Patent number: 5405590
    Abstract: An off-gas quencher and solid recovery scrubber unit includes a wet flue gas scrubber which has the dual responsibilities of lowering the temperature of the inlet hot gas entering through the scrubber and trapping contaminants from the gas stream into the liquid stream. The hot exhaust gases are first cooled by evaporating the liquid scrubber solution. The contaminants of the exhaust gas are neutralized by a suitable reagent such as sodium hydroxide and the product is collected in the scrubbing solution. Since the solution is continuously recycled, the concentration of the scrubbing agent will be diminished as the scrubbing proceeds, while the concentration of the scrubbing product in the solution will rise to the solubility limit of the product. The scrubbing products start to precipitate and are collected at the bottom of the scrubber and are withdrawn. The scrubbing reagents are continuously replenished to the scrubber.
    Type: Grant
    Filed: February 5, 1993
    Date of Patent: April 11, 1995
    Assignees: Pedro Buarque De Macedo, Theodore Aaron Litovitz
    Inventors: Pedro B. D. Macedo, Hamid Hojaji, Marek Brandys, Robert K. Mohr
  • Patent number: 5403559
    Abstract: Device for cleaning exhaust gas of a motor vehicle is disclosed. The device comprises a first honeycomb body having a first diameter and a multiplicity of channels through which the exhaust gas can flow, a diffusor disposed downstream of the first honeycomb body as seen in the direction of flow of the exhaust gas, and a second honeycomb body disposed downstream of the diffusor. The second honeycomb body has a second diameter which is greater than the first diameter.
    Type: Grant
    Filed: July 22, 1993
    Date of Patent: April 4, 1995
    Assignee: Emitec Gesellschaft fuer Emissionstechnologie
    Inventor: Helmut Swars
  • Patent number: 5397545
    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.
    Type: Grant
    Filed: February 14, 1994
    Date of Patent: March 14, 1995
    Assignee: Siemens Aktiengesellschaft
    Inventors: Lothar Balling, Klaus Huettenhofer
  • Patent number: 5364599
    Abstract: A method and A multi-ejector type of system for efficiently purifying the polluted poisonous exhaust gas, which is inevitably generated from the progress of work of the manufactories of various kinds. This multi-ejector type of system comprises a pre-processing part and a post-processing part. The former part preliminarily removes dust from the exhaust gas and causes the temperature of the exhaust gas to be reduced to a predetermined degree, while the latter part neutralizes and washes the exhaust gas, which has been processed in the former part, so as to cause the pollutants to be completely removed from the exhaust gas. Here, the former part is connected to the latter part through a plurality of pipe lines. This multi-ejector type of system has a such simple construction that it is run on a small scale and is inexpensive and this makes the system be easily equipped without expensive burdensome.
    Type: Grant
    Filed: March 15, 1993
    Date of Patent: November 15, 1994
    Assignee: Anico Co. Ltd.
    Inventor: Bup-Jong Lee