Halogenous Component Patents (Class 423/240R)
  • Patent number: 6162957
    Abstract: A method for decomposing a perfluorocarbon in the presence of water vapor or water vapor and molecular oxygen in gas phase, in which a catalyst of a phosphate comprising at least one element selected from the group consisting of aluminum, boron, alkali earth metal, titanium, zirconium, lanthanum, cerium, yttrium, rare earth metal, vanadium, niobium, chromium, manganese, iron, cobalt and nickel, and phosphorus oxide, is used.
    Type: Grant
    Filed: January 18, 2000
    Date of Patent: December 19, 2000
    Assignee: Showa Denko K.K.
    Inventors: Tetsuo Nakajo, Masatoshi Hotta, Hiromoto Ohno, Toshio Ohi, Yusaku Takita
  • Patent number: 6162410
    Abstract: In a method for reducing hydrogen chloride emissions from an asphalt air-blowing process, an asphalt is subjected to an air-blowing process where air is bubbled through hot asphalt to raise the softening point of the asphalt. The fumes from the air-blowing process are bubbled through a liquid seal in a knockout tank before going to an incinerator and finally being emitted to the atmosphere. The knockout tank normally operates to condense oil in the fume stream, and the liquid seal is composed of this oil, as well as some of the water evolved in the air-blowing process. When using ferric chloride or ferrous chloride as a catalyst in the air-blowing process, the fume stream contains significant levels of hydrogen chloride.
    Type: Grant
    Filed: December 30, 1998
    Date of Patent: December 19, 2000
    Assignee: Owens Corning Fiberglass Corporation
    Inventors: Jorge Alberto Marzari, Katherine Elizabeth Poterek, Timothy Thomas Picman
  • Patent number: 6149884
    Abstract: The invention relates to a method of treating germanium-containing gaseous waste coming from a unit for manufacturing an optical fiber preform, the method comprising the following steps:a liquid effluent is formed from the gaseous waste; andthe germanium is precipitated in the liquid effluent. According to the invention, the precipitation is performed by adding magnesium MgO to the liquid effluent.
    Type: Grant
    Filed: September 16, 1999
    Date of Patent: November 21, 2000
    Assignee: Alcatel
    Inventors: Andre Appriou, Laurent Calvo, Gerard Lavanant
  • Patent number: 6146606
    Abstract: A process for decomposing nitrogen fluoride, comprising contacting gaseous nitrogen fluoride with a solid reactive agent for decomposition at 200.degree. C. or more to fix the fluorine component in the nitrogen fluoride to the reactive agent and at the same time control generation of nitrogen oxides, fluorocarbon and carbon monoxide as by-products, the reactive agent containing elemental carbon; aluminum compound, iron compound, manganese compound and/or alkaline earth metal; alkali metal compound; and nickel compound, tin compound and/or copper compound.
    Type: Grant
    Filed: December 28, 1999
    Date of Patent: November 14, 2000
    Assignee: Showa Denko Kabushiki Kaisha
    Inventors: Hitoshi Atobe, Toraichi Kaneko
  • Patent number: 6136281
    Abstract: The present invention relates to a method to catalyze the oxidation of Hg(0) in a flue gas stream prior to standard emissions control equipment. The oxidized mercury has been found to be more condensable than Hg(0) and consequently more easily removed from the gas phase. Accordingly, mercury in its oxidized form can be trapped from a flue gas stream or the like by absorption onto a solid mass or can be more efficiently removed from flue gas streams by wet processes such as a two-stage wet FGD. The gist underlying the inventive concept of the instant invention relates to the use of a porous bed of gold-coated material that is saturated with Hg(0) to the point that the gold in the presence of HCl in the exhaust stream catalyses the oxidation of Hg(0).
    Type: Grant
    Filed: March 31, 1999
    Date of Patent: October 24, 2000
    Assignee: Tennessee Valley Authority
    Inventors: Sandra J. Meischen, Vincent J. Van Pelt
  • Patent number: 6126910
    Abstract: A method is provided for removing contaminants, such as sulfur trioxide, sulfur dioxide and hydrogen halides, out of a gas, such as an exhaust gas from a coal or oil fired burner, by injecting a bisulfite containing solution into the gas so that the bisulfite reacts with the sulfur trioxide and/or hydrogen halides in the gas to produce salts and sulfur dioxide, or by injecting a sulfite containing solution into the gas so that the sulfite reacts the sulfur dioxide in the gas to produce bisulfite and this bisulfite reacts with the sulfur trioxide and/or hydrogen halides to result in the formation of salts and sulfur dioxide. The sulfur dioxide in the gas can be washed out of the gas in a downstream wet scrubber. By removing the sulfur trioxide and/or hydrogen halides out of the gas, corrosion of the gas scrubbing apparatus can be reduced.
    Type: Grant
    Filed: October 13, 1998
    Date of Patent: October 3, 2000
    Inventors: James H. Wilhelm, Robert E. Moser, Frank B. Meserole
  • Patent number: 6123908
    Abstract: A process of treating spent potliner material from aluminum reduction cells and recovering useful products. In the process of the present invention, spent potliner material is introduced into an acid digester containing, for example, sulfuric acid. As a result of this step, a gas component is produced which includes hydrogen fluoride, silicon tetrafluoride and hydrogen cyanide. Also, a slurry component is produced which includes carbon, a refractory material including silica, alumina, sodium compounds such as sodium sulfate, aluminum compounds such as aluminum sulfate, iron compounds such as iron sulfate, magnesium and calcium compounds such as magnesium and calcium sulfate. The slurry component remains in the digester after the gas component is removed. The gas component is recovered and heated an effective amount to convert or decompose the silicon tetrafluoride to fumed silica, hydrogen cyanide to a remaining gas component including CO.sub.2, H.sub.2 O, and nitrogen oxides, as well as HF gas.
    Type: Grant
    Filed: March 27, 1999
    Date of Patent: September 26, 2000
    Assignee: Goldendale Aluminum Company
    Inventors: Robert J. Barnett, Michael B. Mezner
  • Patent number: 6117405
    Abstract: A process is provided for removing contaminants, such as nitrogen oxides, out of exhaust gases, such as gases emitted from an incineration plant. Ammonia or a reducing agent producing ammonia is added to the exhaust gases at a point where the exhaust gases are at a temperature ranging from 700 to 900.degree. C. so that ammonia reacts with and removes nitrogen oxides out of the gases; the gases are passed into a boiler where they are cooled to a temperature ranging from 200 to 350.degree. C. and additional ammonia or reducing agent is injected into the gases; the gases are removed from the boiler and alkaline sorbents, such as alkali metal compounds or alkaline earth metal compounds are injected into the gases, and the gases are passed through a catalyst/filter element coated with a catalytically active oxide or salt of vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, tungsten and molybdenum for catalyzing the reduction of residual nitrogen oxides in the flue gases.
    Type: Grant
    Filed: June 22, 1998
    Date of Patent: September 12, 2000
    Assignee: Von Roll Umwelttechnik AG
    Inventors: Rudolf Frey, Felix Koller
  • Patent number: 6103944
    Abstract: Water present in a hot gaseous product stream from a reactor system A.B (FIG. 1) containing hydrogen fluoride is separated from the stream in order to eliminate a potentially corrosive combination of water and HF. The water is removed by contacting the gaseous product stream with liquid HF in a distillation column so as to obtain a bottoms product containing liquid HF and water and a top product containing dry HF and the product to be recovered. The invention encompasses the separation process, a vessel for carrying out the process (FIGS. 2 to 4), a control system for the liquid HF supply to the distillation column (FIGS. 5 and 6) and a recovery system for recovering HF employed during operation of the reactor system in different regimes employing HF as a fluorination agent, as a diluent during catalyst regeneration and/or catalyst prefluorination (FIG. 7).
    Type: Grant
    Filed: May 2, 1994
    Date of Patent: August 15, 2000
    Assignee: Imperial Chemical Industries PLC
    Inventors: Charles Brian Blake, James Malcolm Forsyth, Ann San Liow, Stephen John Adams, Ralph Jones Doy, Rowland John Porter Brierley, Jane Andrea Eileen Roberts, Brian Schofield, Neil David Shilling
  • Patent number: 6090355
    Abstract: A method for scrubbing flue gases of furnaces includes subjecting the flue gases with addition of activated carbon particles to wet scrubbing in a wet scrubbing device. Activated carbon particles are mixed with particles of at least one compound selected from slaked lime and limestone to produce a particle mixture that is introduced into the flue gases upstream of a flue gas heat exchanger that is positioned upstream of the wet scrubbing device.
    Type: Grant
    Filed: September 9, 1998
    Date of Patent: July 18, 2000
    Assignee: Steag Aktiengesellschaft
    Inventors: Hermann Winkler, Marion Neumann
  • Patent number: 6063353
    Abstract: Krypton and/or xenon are extracted from a krypton-xenon concentrate by means of distillation, for example, a krypton-xenon concentrate obtained from a low-temperature air separation unit. To remove fluorine- and/or chlorine-containing contaminants, especially fluorocarbons, CF.sub.4 and/or SF.sub.6, the krypton-xenon concentrate, a krypton stream and/or a xenon stream are purified in a solid sorbent that contains phyllosilicates.
    Type: Grant
    Filed: March 4, 1998
    Date of Patent: May 16, 2000
    Assignee: Linde Aktiengesellschaft
    Inventors: Karl Baur, Michael Huala, Ralph Spori
  • Patent number: 6060030
    Abstract: A method is provided for abating acidic contaminants, such as sulfur dioxide and hydrogen chloride, in exhaust gases while minimizing the formation of visible plumes of ammonium salts proximate to the outlet of the exhaust stack by injecting a spray of an alkaline liquid, such as sodium hydroxide or potassium hydroxide, into the contaminated exhaust gases wherein the pH of the alkaline liquid is high enough, i.e. greater than a pH of about 11, so that the acidic contaminants preferentially react with the alkaline liquid rather than the ammonia in the gases, thereby minimizing formation of visible plumes of ammonium salts.
    Type: Grant
    Filed: April 20, 1998
    Date of Patent: May 9, 2000
    Inventors: James J. Schwab, Ronald L. Hawks
  • Patent number: 6060031
    Abstract: The device and method of the invention provide a neutralizing compound that reacts with acid gases generated in laser exhaust to yield an insoluble non-toxic powder.
    Type: Grant
    Filed: July 27, 1998
    Date of Patent: May 9, 2000
    Assignee: TRW Inc.
    Inventor: Peter M. Livingston
  • Patent number: 6045766
    Abstract: The invention relates to a process for reducing the residual hydrogen fluoride gases in a fluorinated plastic tank, in particular in a plastic tank for a motor vehicle, in which firstly the space within the tank is subjected to a fluorination step and then, in at least one gas flushing process, the reaction products of the fluorination step are removed from the plastic tank. In a process in which the undesired reaction product hydrogen fluoride is completely eliminated and which is suitable for efficient large-scale production, after the gas flushing process, a neutralization step is carried out to bind residual fluorination gases on the inner layers of the plastic tank.
    Type: Grant
    Filed: May 14, 1999
    Date of Patent: April 4, 2000
    Assignee: Mannesmann VDO AG
    Inventor: Rainer Moser
  • Patent number: 6042802
    Abstract: The present disclosure relates to a method for generating a volume of chlorine dioxide based sterilant/disinfectant. The method includes the step of generating chlorine dioxide gas, and transferring the chlorine dioxide gas to a sterilization chamber. It also includes the step of monitoring the concentration of chlorine dioxide gas within the sterilization chamber, and terminating the transfer of chlorine dioxide gas to the sterilization chamber when the concentration of chlorine dioxide within the chamber reaches a predetermined level.
    Type: Grant
    Filed: October 15, 1997
    Date of Patent: March 28, 2000
    Assignee: Medivators Inc.
    Inventor: James Franklin Drake
  • Patent number: 6033638
    Abstract: A method for adsorbing and oxidizing VOC's in the same bed, thus reducing the size of or even eliminating the need for a catalytic or thermal oxidation unit at the end of the system. In this system, a catalyst is intimately interspersed with the adsorbent material. The catalyst oxidizes VOC's released during desorption when it reaches the `light off temperature,` that is, the catalyst temperature necessary for oxidation to begin. As VOC's are desorbed, they are combusted by the catalyst in the same bed and also by their combustion, heat the bed to aid in the desorption of VOC's elsewhere in the bed.
    Type: Grant
    Filed: March 20, 1998
    Date of Patent: March 7, 2000
    Inventors: Larry E. Campbell, Michele W. Sanders
  • Patent number: 6033639
    Abstract: A method for cleaning process gases is provided, in which a sorbent is supplied to the process gases for reaction with gaseous pollutants that are present therein, thereby forming particulate reaction products which are separated in a subsequent particulate separator, and in which the moisture content and temperature of the cleaned process gases are measured to determine the relative humidity of the process gases and the concentration of at least one of the gaseous pollutants in the cleaned process gases is measured, wherein the relative humidity of the process gases is increased from a substantially constant basic level (BL) to an increased level (IL) and the amount of sorbent supplied to the process gases is increased when the concentration of at least one gaseous pollutant in the cleaned process gases exceeds an upper limit value (UL), and wherein the relative humidity is decreased back to said basic level, after a period of time and/or when the concentration of at least one gaseous pollutant in the cleane
    Type: Grant
    Filed: June 4, 1998
    Date of Patent: March 7, 2000
    Assignee: ABB Flakt AB
    Inventor: Peter Odenmo
  • Patent number: 6030591
    Abstract: A process for recovery of fluorocompound gas from an effluent gas stream containing the fluorocompound gas and other gas components, in which at least one of the other gas components is removed, e.g., by oxidation or contacting of the effluent stream with a dry material such as an adsorbent or scrubber medium, to yield a first effluent gas mixture containing the fluorocompound gas. The fluorocompound gas is removed from the first effluent gas mixture and recovered as a concentrated fluorocompound gas, by a process such as cryogenic processing, membrane separation, and/or adsorption.
    Type: Grant
    Filed: January 2, 1998
    Date of Patent: February 29, 2000
    Assignee: ATMI Ecosys Corporation
    Inventors: Glenn M. Tom, H. Eric Fisher, W. Karl Olander
  • Patent number: 6023007
    Abstract: A method for decomposing a perfluorocarbon in the presence of water vapor or water vapor and molecular oxygen in gas phase, in which a catalyst of a phosphate comprising at least one element selected from the group consisting of aluminum, boron, alkali earth metal, titanium, zirconium, lanthanum, cerium, yttrium, rare earth metal, vanadium, niobium, chromium, manganese, iron, cobalt and nickel, and phosphorus oxide, is used.
    Type: Grant
    Filed: March 23, 1998
    Date of Patent: February 8, 2000
    Assignee: Showa Denko K.K.
    Inventors: Tetsuo Nakajo, Hiromoto Ohno, Toshio Ohi, Yusaku Takita
  • Patent number: 5977427
    Abstract: A process is provided for the destruction of organohalogen compounds, such as methyl chloride, chloroform, carbon tetrachloride, etc., by mixing the organohalogen compounds with a heated carrier gas, such as nitrogen, argon or air, and either steam or water to form a mixture; supplying the mixture to a catalyst, such as titanium oxide/tungsten oxide, to decompose the organohalogen compounds into halogens and hydrogen halides, such as chlorine, hydrochloric acid, fluorine and hydrofluoric acid; conducting the halogen and hydrogen halide contaminated gas through a bent path, created by a baffle that prevents the entry of mist or droplets into the catalyst chamber, into a cooling section where the halogen and hydrogen halide contaminated gas is sprayed with water to cool the gas to a temperature low enough to prevent the formation of dioxines. An alkaline agent, such as sodium hydroxide, can be added to the cooling water to neutralize the halides and hydrogen halides.
    Type: Grant
    Filed: June 5, 1996
    Date of Patent: November 2, 1999
    Assignees: Hitachi, Ltd., Hitachi Engineering Co., Ltd.
    Inventors: Shin Tamata, Satoru Ohashi, Toshihide Takano, Hisao Yokoyama, Toshihiro Mori
  • Patent number: 5907077
    Abstract: A method of treatment of a fleon gas consisting only of carbon and fluorine is provided, wherein the fleon gas is exposed to a plasma to decompose and chemically activate the fleon gas. The fleon gas having been chemically activated is then made into contact with a reactant to form a reaction product.
    Type: Grant
    Filed: March 14, 1997
    Date of Patent: May 25, 1999
    Assignee: NEC Corporation
    Inventor: Keiichi Harashima
  • Patent number: 5904879
    Abstract: An integrated liquefaction and gasification process converts bulk particulate halogen-containing waste plastic materials with minimal particle size reduction into a synthesis gas and a non-leachable, vitreous environmentally nontoxic slag. The process involves melting and cracking bulk particulate halogen-containing waste plastic material to form a lower boiling point, lower molecular weight halogen-containing oil composition which then undergoes partial oxidation in a quench gasifier to produce a synthesis gas. Any hazardous gases, liquids or solids that are produced can be purified into commercially valuable byproducts or recycled to the process, which does not release hazardous materials to the environment.
    Type: Grant
    Filed: August 8, 1997
    Date of Patent: May 18, 1999
    Assignee: Texaco Inc
    Inventors: John Duckett Winter, Paul Ellis Brickhouse, Ronald Frederick Tyree, John S. Stevenson, Gregory Joseph Mayotte, Jerrold Samuel Kassman, Byron Von Klock
  • Patent number: 5904909
    Abstract: A method for the removal and rapid decomposition of halogenated fumigation agents is described. A fumigation agent, such as methyl bromide, contained in the gas stream exiting a fumigation chamber or structure is captured on activated carbon or other retentive substrate and rapidly decomposed using thiosulfate and water. The method provides an inexpensive, safe, and on-site executable way to remove and detoxify methyl bromide from fumigation discharge gases, thereby reducing or eliminating methyl bromide emissions into the atmosphere.
    Type: Grant
    Filed: August 21, 1997
    Date of Patent: May 18, 1999
    Assignees: The United States of America as represented by the Secretary of Agriculture, The Regents of the University of California
    Inventors: Scott R. Yates, Jianying Gan
  • Patent number: 5897847
    Abstract: A method for extending the gas lifetime of an excimer laser by removing CF.sub.4 impurity, which comprises:a) reacting CF.sub.4, an undesirable impurity which forms and is contained in the lasing gases, with an amount of an oxidizing gas additive effective to produce one or more compounds which are condensible with refrigeration means, without reducing laser output below a predetermined acceptable level; andb) condensing said one or more compounds produced in step a) with refrigeration means, substantially without condensing said one or more rare gases therewith, thereby removing said CF.sub.4 impurity from said excimer laser and extending the gas lifetime of the laser.
    Type: Grant
    Filed: September 1, 1993
    Date of Patent: April 27, 1999
    Assignee: American Air Liquide
    Inventors: Gregory M. Jursich, William A. Von Drasek
  • Patent number: 5895636
    Abstract: Methods and chemical compositions for treating a gas stream comprising non-halogenated and halogenated organic compounds while suppressing halogenation of the non-halogenated organic compounds with the oxidation products of the halogenated organic compounds in the gas stream are disclosed. The gas stream in the presence of oxygen is contacted with the catalyst compositions of the invention to oxidize the non-halogenated and the halogenated compounds to form water, carbon dioxide, and halogen molecules (Cl.sub.2, Br.sub.2, etc.) and/or halogen acids such as HCl, HBr, etc. An advantage of the present compositions and methods is that halogenation or of the treated emissions is suppressed over a process operating temperature range 400 to 550.degree. C.
    Type: Grant
    Filed: December 2, 1997
    Date of Patent: April 20, 1999
    Assignee: Engelhard Corporation
    Inventors: Pascaline H. Nguyen, James M. Chen, Chung-Zong Wan, Shau-Lin Frank Chen, Zhicheng Hu
  • Patent number: 5885539
    Abstract: The treatment, through a dry adsorption process, of a gas from a hot electrolytic process for aluminum production comprises at least two stages. Particulate aluminum oxide (the adsorbent) passes through the stages of the adsorption process countercurrently to the gas. Thus, the gas is treated with a partly spent adsorbent in a first dry adsorption stage, whereupon the particulate adsorbent is separated from the gas downstream from the first adsorption stage. Part of the separated particulate adsorbent is removed from the adsorption process for recycling adsorbed fluorine-containing substances to the electrolytic process. The remainder of the separated adsorbent is recirculated in the first adsorption stage in order to optimize the adsorption of fluorine-containing substances and the desorption of sulfur dioxide from the aluminum oxide in this stage. Simultaneously, the gas is transferred to a second dry adsorption stage.
    Type: Grant
    Filed: June 9, 1997
    Date of Patent: March 23, 1999
    Assignee: ABB Flakt AB
    Inventors: Odd E. Bjarn.o slashed., Geir Wedde
  • Patent number: 5877391
    Abstract: A method for treating a gas flow containing organohalogen compounds including the steps of contacting the gas flow with a catalyst at a temperature below 500.degree. C. in the presence of an effective amount of steam, wherein the catalyst contains titania, tungsten oxide, and silica, the Ti and W are present in the range of 20-95 mol % Ti and 5-80 mol % W based on Ti and W, and the amount of silica is in the range of 0.5-15% by weight silica to 100% by weight titania. Accordingly, the organohalogen compound can be decomposed effectively to carbon monoxide, carbon dioxide, and hydrogen halide.
    Type: Grant
    Filed: March 4, 1997
    Date of Patent: March 2, 1999
    Assignee: Hitachi, Ltd.
    Inventors: Shuichi Kanno, Hiroshi Kawagoshi, Akira Kato, Toshiaki Arato, Hisao Yamashita, Shigeru Azuhata, Shin Tamata, Shinzo Ikeda, Takeshi Yasuda
  • Patent number: 5866091
    Abstract: The present invention relates to a method for minimizing hydrogen halide corrosion in quench gasifier during the non-catalytic partial oxidation reaction of a halogen-containing hydrocarbonaceous feed, to produce a hydrogen halide-containing synthesis gas, finely divided particulate solids, and a nontoxic slag. The hydrogen halide-containing synthesis gas is contacted with water in the quench zone of the gasifier. The quench water contains a neutralizing agent, in excess of the amount necessary to neutralize hydrogen halide acids present therein, to thereby form halide salts. The quench water containing the halide salts is purified to recover the halide salts. The salt-free water is essentially environmentally non-toxic and can either be recycled to the process or discarded in conformity with environmental regulations.
    Type: Grant
    Filed: July 9, 1997
    Date of Patent: February 2, 1999
    Assignee: Texaco Inc
    Inventors: John Saunders Stevenson, Byron Von Klock, John Duckett Winter, Jerrold Samuel Kassman, George Henry Webster, Jr., Paul Ellis Brickhouse
  • Patent number: 5855647
    Abstract: A process for recovering SF.sub.6 from a gas is provided. The process includes the step of contacting a gas stream comprising SF.sub.6 and at least one of N.sub.2, O.sub.2, CO.sub.2, and H.sub.2 O with a membrane in at least one membrane separation unit at conditions effective to obtain a retentate stream rich in SF.sub.6 and a permeate stream rich in at least one of N.sub.2, O.sub.2, CO.sub.2, and H.sub.2 O.
    Type: Grant
    Filed: May 15, 1997
    Date of Patent: January 5, 1999
    Assignee: American Air Liquide, Inc.
    Inventors: Yao-En Li, Magdy Meimari
  • Patent number: 5830423
    Abstract: The gas stream which is produced in and emanates from landfills, anaerobic digesters and other waste gas streams, is treated to produce a purified gas which is essentially a hydrocarbon such as methane and which can be used as the fuel source in a fuel cell power plant. The gas stream passes through a simplified purification system which removes essentially all of the sulfur compounds, hydrogen sulfide, and halogen compounds from the gas stream. The resultant gas stream can be used to power a fuel cell power plant which produces electricity, or as a hydrocarbon fuel gas for other applications.
    Type: Grant
    Filed: November 22, 1995
    Date of Patent: November 3, 1998
    Assignee: International Fuel Cells Corp.
    Inventors: John C. Trocciola, Roger R. Lesieur, John L. Preston, Jr., Richard A. Sederquist
  • Patent number: 5821395
    Abstract: This invention relates to a process for thermally cracking waste polymer(s) comprising chlorinated polymers in a reactor in the presence of a fluidizing gas and a fluidized bed of solid, particulate fluidizable material at a temperature from 350.degree.-600.degree. C. to cracked products comprising a mixed vapor of lower hydrocarbons which have a chlorine content of less than 50 ppm. In the process, the cracked products emerging from the fluidized bed are passed through one or more guard beds comprising calcium oxide or a compound capable of giving rise to calcium oxide under the reaction conditions maintained at a temperature in the range from 400.degree.-600.degree. C. in such a way that the chlorine content of the product is less than 50 ppm.
    Type: Grant
    Filed: June 5, 1995
    Date of Patent: October 13, 1998
    Assignee: BP Chemicals Limited
    Inventors: Alan George Price, David Charles Wilson
  • Patent number: 5814127
    Abstract: A process for recovering at least one of CF.sub.4 and C.sub.2 F.sub.6 from a vent gas from an aluminum electrolysis cell. The process includes the steps of:(a) removing inorganic fluorides from a vent gas comprising inorganic fluorides and at least one of CF.sub.4 and C.sub.2 F.sub.6 to obtain a purified vent gas; and(b) contacting the purified vent gas with a membrane at conditions effective to obtain a retentate stream rich in at least one of CF.sub.4 and C.sub.2 F.sub.6, and a permeate stream depleted in at least one of CF.sub.4 and C.sub.2 F.sub.6.
    Type: Grant
    Filed: December 23, 1996
    Date of Patent: September 29, 1998
    Assignee: American Air Liquide Inc.
    Inventor: Yao-En Li
  • Patent number: 5779998
    Abstract: A process for recovery of halocarbons from a gas mixture containing the halocarbon and acid gas components comprises the steps of contacting the gas mixture with a dry scrubber to remove the acid gas components from the gas mixture and yield a first effluent gas mixture containing the halocarbon. The first effluent gas mixture is contacted with an adsorbent which is selective for the halocarbon component of the first effluent gas mixture to adsorb the halocarbon component and yield a second effluent gas. The adsorbed halocarbon is recovered by desorbing same from the adsorbent. The process of contacting with adsorbent can be carried out in at least two adsorbent beds joined at inlet and outlet ends thereof to gas feed and gas discharge manifolds, respectively.
    Type: Grant
    Filed: December 5, 1996
    Date of Patent: July 14, 1998
    Assignee: ATMI EcoSys Corporation
    Inventor: Glenn M. Tom
  • Patent number: 5779999
    Abstract: A method for scrubbing flue gases utilizing a spray tower for removing acidic gases and particulate matter from flue gases produced by processing operations of the type carried out in utility and industrial facilities. The spray tower is equipped with a tank that serves as a reservoir for an alkaline slurry used to remove acidic gases and particulate matter from the flue gases. The slurry is pumped from the tank to spraying devices located within the tower. The spray tower further includes an internal structure that enables the slurry to be oxidized and gently agitated within a limited region of the tank, and without the requirement for two separate aeration and agitation devices. As a result, the construction, operational and maintenance costs of the spray tower are significantly reduced as compared to prior art spray towers.
    Type: Grant
    Filed: February 27, 1997
    Date of Patent: July 14, 1998
    Assignee: Marsulex Environmental Technologies, LLC
    Inventor: Dennis J. Laslo
  • Patent number: 5766483
    Abstract: A method for separating hydrogen fluoride from a chemical mixture is provided. In the process of the invention, hydrogen fluoride is separated from a chemical mixture containing hydrogen fluoride by contacting the chemical mixture with a hydrogen fluoride binder. The separated hydrogen fluoride may be recovered from the hydrogen fluoride binder.
    Type: Grant
    Filed: May 10, 1996
    Date of Patent: June 16, 1998
    Assignee: AlliedSignal Inc.
    Inventors: Mathew Hermes Luly, Jeffrey Warren Mckown, Robert Pratt, Rajiv Ratna Singh, Paul Frederick Kunkel, Charles Lewis Redmon, Hang Thanh Pham
  • Patent number: 5756060
    Abstract: A process for cleaning a harmful gas which comprises bringing a harmful gas containing a halogen gas and/or a halogen compound gas such as hydrogen fluoride, hydrogen chloride, tungsten hexafluoride, silicon tetrafluoride and boron trifluoride into contact with a cleaning agent comprising metal oxides composed principally of copper (II) oxide and manganese (IV) oxide that are spreadingly and adhesively incorporated with sodium formate so as to remove a harmful component from the harmful gas. According to the cleaning process of the present invention, it is possible to remove harmful components from the harmful gas in extremely high efficiency at ordinary temperature, dispensing with heating or cooling irrespective of the concentration of the harmful components. The cleaning capacity of the cleaning agent is favorably maintained without deterioration even when the harmful gas is in a dry state.
    Type: Grant
    Filed: November 4, 1996
    Date of Patent: May 26, 1998
    Assignee: Japan Pionics Co., Ltd.
    Inventors: Kenji Otsuka, Satoshi Arakawa, Youji Nawa
  • Patent number: 5730948
    Abstract: A method for producing chlorine dioxide by moving fluid (such as air) relative to (e.g. flowing the fluid through) a first bed of zeolite crystals impregnated with at least one of the following: phosphoric acid, acetic acid and citric acid, and then moving the fluid relative to a second bed of zeolite crystals impregnated with sodium chlorite and/or zeolite crystals impregnated with chlorine. Optionally, at least some of the produced chlorine dioxide is absorbed by moving the fluid relative to (e.g., flowing the fluid through) a third bed of chemically impregnated zeolite crystals.
    Type: Grant
    Filed: August 28, 1996
    Date of Patent: March 24, 1998
    Assignees: Klatte Inc., Environmental Safety Systems, Inc.
    Inventors: Fred Klatte, James Aamodt
  • Patent number: 5723097
    Abstract: A method of treating spent potliner material from aluminum reduction cells is disclosed. The spent potliner material is introduced into a sulfuric acid digester to produce a gas component including hydrogen fluoride and hydrogen cyanide and a slurry component including carbon, silica, alumina, sodium sulfate, iron, calcium and magnesium. The gas component is recovered and heated an effective amount to eliminate hydrogen cyanide and produce a remaining gas component including CO.sub.2, H.sub.2 O, nitrogen oxides and HF. The remaining gas component is directed through a water scrubber to form hydrofluoric acid, and the hydrofluoric acid is admixed with aluminum hydroxide to create aluminum fluoride. The slurry component is rinsed with water to separate a first solid fraction containing carbon, alumina and silica from a second liquid faction. The pH of the liquid fraction is adjusted to first create and separate aluminum hydroxide and then to separate sodium sulfate.
    Type: Grant
    Filed: December 8, 1995
    Date of Patent: March 3, 1998
    Assignee: Goldendale Aluminum Company
    Inventors: Robert J. Barnett, Michael B. Mezner
  • Patent number: 5711924
    Abstract: A process for eliminating organic pollutant residues in the synthesis gas occurring during refuse gasification by the addition of oxygen, in which at least prepyrolyzed, carbon-containing refuse in compressed form is fed into a high temperature reactor, where a loosely heaped gasification bed is formed and is burnt below the same by oxygen addition. The resulting synthesis gas is drawn off from the top area of the high temperature reactor after an adequate residence time and into the residence zone. Additional oxygen is then jetted in temperature-regulated, partial quantities in such a way that the resulting possible partial combustion of the synthesis gas maintains its temperature above the gasification bed constant at approximately 1000.degree. C. Oxygen jetting takes place in such a way that a completely homogeneous gas mixing is ensured in the top area. For this purpose, several oxygen jets are arranged in the top area of the high temperature reactor and are axially and/or radially inclined thereto.
    Type: Grant
    Filed: March 22, 1995
    Date of Patent: January 27, 1998
    Assignee: Thermoselect AG
    Inventor: Gunter H. Kiss
  • Patent number: 5711016
    Abstract: The invention relates to the conditioning or packaging of radioactive iodine, particularly iodine 129, using an apatite as the confinement matrix. Having the iodine, said apatite corresponds to the formula:M.sub.10 (XO.sub.4).sub.6-6x (PO.sub.4).sub.6x I.sub.2 (I)in which M represents Cd or Pb, X represents V or As, I is the radioactive iodine to be conditioned and x is such that 0.ltoreq.x<1. This iodoapatite (1) can be surrounded by an apatite (3) not containing iodine serving as a physical barrier.The iodoapatite can be obtained from a solid compound of the iodine, e.g. an iodide such as silver iodide or lead iodide, by reaction with a compound of formula:M.sub.3 (XO.sub.4).sub.2-2x (PO.sub.4).sub.2x (II)orM.sub.10 (XO.sub.4).sub.6-6x (PO.sub.4).sub.6x Y.sub.2 (III)in which M, X and x are as defined hereinbefore and Y can represent OH, F, Cl or O.sub.1/2.
    Type: Grant
    Filed: October 24, 1996
    Date of Patent: January 20, 1998
    Assignee: Commissariat a l'Energie Atomique
    Inventors: Joelle Carpena, Fabienne Audubert, Jean-Louis Lacout
  • Patent number: 5688479
    Abstract: The invention relates to a process for removing hydrogen halides from hydrocarbon containing streams. More particularly, the invention relates to a process and an HCl sorbent for the removal of HCl and other hydrogen halides from hydrocarbon streams to prevent the formation of green acids. The sorbent has a high capacity for sorption of HCl, sufficient physical strength to permit operation in packed bed form, and catalytic inertness to not causing the oligomerization reactive hydrocarbons such as olefins, diolefins. The HCl sorbent comprises an admixture of magnesium hydroxide and a hydrogen halide reactive component such as calcium hydroxide or oxide with at least one or more metal oxide, hydroxide or carbonate wherein the magnesium is present in an amount greater than about 5 mol-% of the total cation content of the sorbent.
    Type: Grant
    Filed: April 5, 1996
    Date of Patent: November 18, 1997
    Assignee: UOP
    Inventor: Chien C. Chao
  • Patent number: 5653949
    Abstract: A catalyst and process for treating gas streams which contain halogenated organic compounds, non-halogenated organic compounds, carbon monoxide or mixtures thereof, and particularly gas streams which contain organobromides. The catalyst comprises at least one platinum group metal, zirconium oxide and at least one oxide of manganese, cerium or cobalt.
    Type: Grant
    Filed: June 28, 1996
    Date of Patent: August 5, 1997
    Assignee: Engelhard Corporation
    Inventors: James M. Chen, Pascaline H. Nguyen
  • Patent number: 5650128
    Abstract: Apparatuses and methods for treating gas streams containing variations in VOC concentration whereby the VOC's are destroyed in a combination non-catalytic/catalytic oxidation system are disclosed. A non-catalytic destruction matrix composed of inert ceramic materials that enhance process mixing and provide thermal inertia for process stability is used when VOC concentrations are high and a catalytic oxidizer is principally used when VOC concentrations are low. The exhaust from the non-catalytic destruction matrix is passed through the catalytic oxidizer to maintain proper catalytic oxidizer operating temperatures. Supplemental fuel and air are added as appropriate upstream or downstream of the non-catalytic oxidizer to maintain proper heat values in each portion of the system.
    Type: Grant
    Filed: December 1, 1994
    Date of Patent: July 22, 1997
    Assignee: Thermatrix, Inc.
    Inventors: Mark Holst, Richard J. Martin
  • Patent number: 5632966
    Abstract: The present invention provides a convenient method for separating hydrogen fluoride from a chemical mixture. More specifically, a method is provided in which hydrogen fluoride is separated from a chemical mixture containing at least one organic material by contacting the chemical mixture with a hydrogen fluoride binder. The hydrogen fluoride separated from the chemical mixture is readily recoverable from the hydrogen fluoride binder.
    Type: Grant
    Filed: March 7, 1996
    Date of Patent: May 27, 1997
    Assignee: AlliedSignal Inc.
    Inventors: Michael Van Der Puy, Mathew H. Luly
  • Patent number: 5618508
    Abstract: An enhanced calcium hydroxide, a process for its manufacture and a process for its use in the removal of volatile heavy metals from a gas is disclosed.
    Type: Grant
    Filed: February 8, 1994
    Date of Patent: April 8, 1997
    Assignee: FTU GmbH Technische Entwicklung und Forschung im Umweltschutz
    Inventors: Hermann Suchenwirth, Roland Fichtel
  • Patent number: 5616253
    Abstract: The present invention relates to various methods, such as an above-ground method and an in-ground method, of using a palladized iron bimetallic system for the dechlorination of chlorinated organic compounds from various effluents or contaminated soil containing the same. The use of palladized iron bimetallic system results in the dechlorination of the chlorinated organic compound into environmentally safe reaction products.
    Type: Grant
    Filed: March 25, 1996
    Date of Patent: April 1, 1997
    Assignee: Research Corporation Technologies, Inc.
    Inventors: Quintus Fernando, Rosy Muftikian, Nic Korte
  • Patent number: 5616160
    Abstract: The invention relates to a process of eliminating high chloride-containing incinerator ash and incinerator ash-residue mixtures, without generating excessive heavy metal-containing effluents during the actual vitrification of the ash. The process involves first pretreating the incinerator ash or ash-residue mixture, if needed, whereby the resultant ash contains less than about 3% halogen by weight and less than about 3% C.. Following the pretreatment, the ash is dried and then mixed with any additives needed to make up a vitrifiable batch mixture which will, when subsequently vitrified, form a glass possessing an excellent acid durability. A durability whereby such that the weight loss of the glass in 5% HCl solution at 95.degree. C. is 2.0 mg/cm.sup.2 or less in 24 hours. This durability results in minimal or non-detectable leaching of hazardous heavy metal or non-metallic specie and is sufficient enough durability such that the vitrified glass will easily pass the EPA's test for leachability.
    Type: Grant
    Filed: January 27, 1995
    Date of Patent: April 1, 1997
    Assignee: Corning Incorporated
    Inventors: M. Grayson Alexander, John L. Stempin, Dale R. Wexell
  • Patent number: 5611963
    Abstract: The invention is a method for reducing halide content of a synthesis gas stream by mixing a metal compound of potassium oxide, potassium hydroxide, potassium bicarbonate, potassium carbonate, sodium oxide, sodium hydroxide, sodium bicarbonate, or sodium carbonate, with a carbonaceous feed material which contains halide-containing compounds; gasifying the carbonaceous feed material in an entrained flow gasifier under gasifying conditions thus producing a synthesis gas containing hydrogen and carbon monoxide; where the metal compound vaporizes and the vaporized metal compound reacts with the halide from the halide-containing compounds, thus producing a vaporized metal halide; cooling the vaporized metal halide, thus producing solid metal halide particles; passing the synthesis gas stream to a solids removal unit for removing the solid metal halide particles; and recovering the synthesis gas stream substantially free of halide-containing compounds.
    Type: Grant
    Filed: August 24, 1994
    Date of Patent: March 18, 1997
    Assignee: Shell Oil Company
    Inventor: Phillip E. Unger
  • Patent number: 5607654
    Abstract: A method and apparatus for minimizing the environmental release of acids and toxic organic compounds from a waste incinerator-air pollution control train. The apparatus comprises an incinerator, a gas cooling means such as a waste heat boiler or quench chamber, a means for the partial removal of acid gases and dioxins by contact with either finely-divided alkaline solids or alternatively, by an alkaline solution in a spray drier-absorber, a dry solids collection means such as a fabric filter or electrostatic precipitator, a wet scrubber means for residual metal, dioxin/acid gas removal and an induced draft fan. In the method of this invention, the final wet scrubber stage operates without alkaline neutralization, but under scrubber acid concentrations and operating conditions that provide an exhaust gas within compliance limits of emission regulations. The contaminated liquor blowdown from the wet scrubber, which contains toxic organics and acids, is recycled back into the incinerator.
    Type: Grant
    Filed: October 24, 1995
    Date of Patent: March 4, 1997
    Assignee: Beco Engineering Company
    Inventor: Bernard J. Lerner
  • Patent number: 5578283
    Abstract: A catalyst and process for treating gas streams which contain halogenated organic compounds, non-halogenated organic compounds, carbon monoxide or mixtures thereof, and particularly gas streams which contain organobromides. The catalyst comprises at least one platinum group metal, zirconium oxide and at least one oxide of manganese, cerium or cobalt.
    Type: Grant
    Filed: December 30, 1994
    Date of Patent: November 26, 1996
    Assignee: Engelhard Corporation
    Inventors: James M. Chen, Pascaline H. Nguyen