Sewage Treatment Patents (Class 48/197A)
  • Patent number: 6063355
    Abstract: A method of treating wastes includes partially combusting the wastes in a fluidized bed reactor at a relatively low temperature followed by separate gasification of gaseous material and char from the first gasification in a separate relatively high temperature reactor. This forms synthesis gas that is cooled, subjected to a conversion operation to produce hydrogen.
    Type: Grant
    Filed: January 21, 1999
    Date of Patent: May 16, 2000
    Assignees: Ebara Corporation, UBE Industries, Ltd.
    Inventors: Hiroyuki Fujimura, Yoshio Hirayama, Shosaku Fujinami, Shuichi Nagato, Tetsuhisa Hirose, Takahiro Oshita, Masaaki Irie, Kazuo Takano, Toshio Fukuda
  • Patent number: 6059972
    Abstract: A tank (1) for an apparatus for receiving and conditioning organic waste by anaerobic bioconversion, in particular, waste produced by restaurant kitchens and other facilities, includes a main enclosure wherein bioconversion takes place, and a secondary enclosure (18) for receiving and storing ground organic waste before it is transferred to the main enclosure for completion of its bioconversion. A hopper (4) or other device for receiving the organic waste is associated with a grinder (2) and is connected to the secondary enclosure (18) of the tank for feeding the ground organic waste. A recirculation system (12, 15) for recycling the contents of the tank includes a pump (13), means for distributing (17a, 17b) the contents of the main enclosure between the different levels thereof, and separate means (9, 22) for removing solid residues and liquid waste.
    Type: Grant
    Filed: August 21, 1998
    Date of Patent: May 9, 2000
    Inventor: Fran.cedilla.ois-Regis Mahrer
  • Patent number: 5980858
    Abstract: A method and apparatus for treating wastes by two-stage gasification recovers metals or ash content in the wastes in such a state that they can be recycled, and gases containing carbon monoxide (CO) and hydrogen gas (H.sub.2) for use as synthesis gas for ammonia (NH.sub.3) or production of hydrogen gas. The wastes are gasified in a fluidized-bed reactor at a low temperature. Then, gaseous material and char produced in the fluidized-bed reactor are introduced into a high-temperature combustor, and gasified at a high temperature and ash content is converted into molten slag. After water scrubbing and a CO conversion reaction, the gas is separated into H.sub.2 and residual gas. The residual gas is then supplied to the fluidized-bed reactor as a fluidizing gas.
    Type: Grant
    Filed: October 22, 1997
    Date of Patent: November 9, 1999
    Assignees: Ebara Corporation, Ube Industries, Lt.
    Inventors: Hiroyuki Fujimura, Yoshio Hirayama, Shosaku Fujinami, Kazuo Takano, Masaaki Irie, Tetsuhisa Hirose, Shuichi Nagato, Takahiro Oshita, Toshio Fukuda
  • Patent number: 5916437
    Abstract: The present invention provides treatment of domestic sewage containing oil. The resulting products will be purified water, dry fertilizer, and fuel (gas and liquid) containing no contaminants that could pollute the environment. After the initial settling process, two parallel flows are created: one containing liquid plus crude sediment (0.2 mm and greater) and the other containing liquid and fine particles (less than 0.2 mm), the latter termed "settled domestic sewage". The two flows are treated separately. The settled domestic sewage after treatment in a low-pressure separator that will separate out liquid fuel, followed by aeration, ultrafiltration, and finally sterilization by ozone or chlorine, results in pure water. The biochemical treatment of the sediments results in the production of gas fuel containing mainly methane gas and solid product that after drying and disinfecting is converted into fertilizer.
    Type: Grant
    Filed: May 5, 1997
    Date of Patent: June 29, 1999
    Inventor: Mikhail Levitin
  • Patent number: 5914284
    Abstract: A system is provided for processing a volume of human sludge with sea water and chemical reactants to generate methane gas and to reduce the volume by at least eighty percent (80%). This is by having a series of processing containers for receiving, holding and processing the sludge volume by way of a volume of sea water and chemical reactants. A first processing container is constructed with a means for mechanically agitating the sludge volume and collecting methane gas released therefrom. The system further has a second processing container for processing a sludge mixture transferred from the first processing container for further treatment of said sludge mixture by sea water and chemical reactants with a means for collecting methane gas released therefrom. A filter system for filtering said sludge volume and said sludge mixture is included in each of the processing containers.
    Type: Grant
    Filed: August 4, 1997
    Date of Patent: June 22, 1999
    Inventor: Kenneth Heuer
  • Patent number: 5900224
    Abstract: A method and apparatus for treating wastes by gasification recovers metals or ash content in the wastes in such a state that they can be recycled, and gases containing carbon monoxide (CO) and hydrogen (H.sub.2) for use as synthesis gas of ammonia (NH.sub.3). The wastes are gasified in a fluidized-bed reactor at a relatively low temperature, and gaseous material and char produced in the fluidized-bed reactor are introduced into the high-temperature combustor. The synthesis gas is produced in the high-temperature combustor at a relatively high temperature, CO and H.sub.2 O in the synthesis gas is converted into CO.sub.2 and H.sub.2, and then H.sub.2 is recovered by removing CO.sub.2.
    Type: Grant
    Filed: November 27, 1996
    Date of Patent: May 4, 1999
    Assignees: Ebara Corporation, Ube Industries, Ltd.
    Inventors: Hiroyuki Fujimura, Yoshio Hirayama, Shosaku Fujinami, Shuichi Nagato, Tetsuhisa Hirose, Takahiro Oshita, Masaaki Irie, Kazuo Takano, Toshio Fukuda
  • Patent number: 5792313
    Abstract: In the evaporation of process wastewater comprising a mixture of different types of wastewater, problems arise due to the formation of reaction products, so-called incrustations, which are difficult to separate. These incrustations clog up the evaporator, thus necessitating frequent stoppages for chemical and mechanical cleaning of the evaporator. The invention concerns an improved method for concentrating process wastewater by evaporation. In this method, one acid process flow and one alkaline process flow are evaporated alternately in one and the same evaporator. With this method, precipitates that are difficult to separate are dissolved in the evaporator during the respective evaporations. As a result, stoppages motivated by the need to clean the evaporator may be avoided to the utmost possible extent, while less and cheaper processing equipment is required.
    Type: Grant
    Filed: June 10, 1996
    Date of Patent: August 11, 1998
    Assignee: Eka Nobel AB
    Inventor: Hans Johansson
  • Patent number: 5788723
    Abstract: A process for the high-temperature gasification of possibly thermally pretreated heterogeneous wastes, in which oxygen is injected into the gasification bed with the aid of water-cooled oxygen lances. The oxygen is heated by an independent pilot flame and accelerated to speeds approaching the speed of sound. Accordingly, the oxygen lances cannot be plugged by melted charge components not susceptible to gasification because the pilot flame is driven independently of the oxygen-lance flow. A pulsing, phase-shifted impact from several oxygen lances arranged in a ring produces a circulating flow of material in the gasification zone, compensating the heterogeneity of the charge in the case of a waste gasification.
    Type: Grant
    Filed: February 13, 1997
    Date of Patent: August 4, 1998
    Assignee: Thermoselect AG
    Inventor: Gunter H. Kiss
  • Patent number: 5681360
    Abstract: A process for concentrating and recovering methane and carbon dioxide from landfill gas includes absorption of commonly occurring pollutants using a reduced amount of carbon dioxide absorbent which itself may be an in situ derived and recoverable constituent. Separated methane may be concentrated into a high heating value fuel, and a highly pure food-grade carbon dioxide product may also be recovered. Process streams may be used to provide fuel for compression and refrigeration and/or to regenerate carbon dioxide absorbent.
    Type: Grant
    Filed: January 11, 1995
    Date of Patent: October 28, 1997
    Assignee: Acrion Technologies, Inc.
    Inventors: Lawrence A. Siwajek, W. Jeffrey Cook, William R. Brown
  • Patent number: 5656042
    Abstract: A pumpable slurry of shredded scrap solid carbonaceous plastic-containing material that contains associated inorganic matter in admixture with a comminuted aluminosilicate-containing material having noncombustible constituents is reacted by partial oxidation to produce synthesis gas, reducing gas, or fuel gas. The noncombustible constituents in the aluminosilicate-containing material captures the inorganic matter in the scrap solid carbonaceous plastic-containing material while in the reducing atmosphere of the gasifier to produce nontoxic, nonleachable slag. The slurrying medium is water, liquid hydrocarbonaceous fuel, or mixtures thereof. Scrap plastics may be disposed of by the subject process without polluting the nation's environment.
    Type: Grant
    Filed: May 24, 1994
    Date of Patent: August 12, 1997
    Assignee: Texaco Inc.
    Inventors: Motasimur Rashid Khan, Christine Cornelia Albert, John Saunders Stevenson, George Neal Richter, David Charles Crikelair
  • Patent number: 5464539
    Abstract: The present invention relates to a process for the production of hydrogen comprising treating in an anaerobic condition a substrate such as waste water including organic matter using sludge compost, whereby stable hydrogen generation at a higher efficiency for a longer period of time is attained together with the treatment of waste water.
    Type: Grant
    Filed: September 2, 1994
    Date of Patent: November 7, 1995
    Assignees: Kajima Corporation, Research Institute of Innovative Technology for the Earth
    Inventors: Yoshiyuki Ueno, Masayoshi Morimoto, Seiji Ootsuka, Tatsushi Kawai, Susumu Satou
  • Patent number: 5423992
    Abstract: A chemically disinfected sewage sludge-containing material comprising (1) an aqueous slurry of sewage sludge-containing material having a solids content in the range of about 10 to 30 wt. %; and (2) a chemical disinfectant comprising a water soluble silicate of sodium in the amount of 5 to 20 wt. % (basis dry wt. of said sewage sludge). In one embodiment, a pumpable chemically disinfected sewage sludge-containing material was produced by the steps of (1) dewatering sewage sludge to produce an aqueous slurry having a solids content of about 10 to 30 wt. %; (2) shearing the dewatered sewage sludge from (1) at a temperature in the range of about ambient to 230.degree. F. and at a shear rate of at least 30 per second for a period in the range of about 0.5 to 180 minutes; and (3) mixing the following materials together at a temperature in the range of about ambient to 230.degree. F. to produce a pumpable aqueous slurry having a solids content in the range of about 30 to 65 wt.
    Type: Grant
    Filed: May 20, 1991
    Date of Patent: June 13, 1995
    Assignee: Texaco Inc.
    Inventors: Matthew A. McMahon, Mitri S. Najjar, Peter D. Robison, Ronald J. McKeon
  • Patent number: 5423891
    Abstract: Direct gasification of a high BTU content fuel gas from a hydrocarbon content solid waste material W which may include some glass content is effected by preheating heat carrier solids HCS in a flash calciner to a temperature capable of thermally cracking the hydrocarbon content of the solid waste material W directly into the high BTU content fuel gas. The HCS are separated from the products of combustion and fed into a gas sealed refractory lined horizontal axis rotary kiln retort concurrently with the solid waste W. Momentary contact and mixing of the solid waste W with the HCS in the rotary kiln in the absence of oxygen is sufficient to directly thermally crack the solid waste material into the high BTU gas product. Separated HCS are returned to the flash calciner for reheating.
    Type: Grant
    Filed: May 6, 1993
    Date of Patent: June 13, 1995
    Inventor: Robert A. Taylor
  • Patent number: 5423895
    Abstract: A gas-holding sludge digester is disclosed having a sideskirt which telescopes in a liquid chamber which is separate from a main digester tank and wherein the ballast is structured to increase gas pressure of the gas contained within the cover as the sideskirt telescopes upward.
    Type: Grant
    Filed: August 23, 1993
    Date of Patent: June 13, 1995
    Assignee: Baker Hughes Incorporated
    Inventors: Jeffrey L. Wight, Lynn W. Cook, David P. Brown
  • Patent number: 5370715
    Abstract: Organic wastes of diverse types including toxic materials are converted to synthesis gas or molecular hydrogen or methanol and an inorganic solid residue by heating the material to 1200 .degree. C. or higher in the presence of steam in a chemically reducing atmosphere. The gassified wastes travel along a vertical flow path in a sealed reactor vessel. Heat is applied by vertically extending recuprative heaters situated at both lower and upper regions along the flow path to provide a high temperature zone of sufficient length to thermally decompose the wastes during a single passage along the path. Steam may be provided by intermixing liquid water, which may be dirty and/or contaminated, into the wastes prior to entry of the wastes into the reaction chamber thereby avoiding any need for an external boiler and pure water. The apparatus realizes a very high throughput and does not release any pollutants into the air, ground or water.
    Type: Grant
    Filed: April 27, 1993
    Date of Patent: December 6, 1994
    Inventors: Robert N. Kortzeborn, William D. Gwinn
  • Patent number: 5356540
    Abstract: A pumpable aqueous slurry of sewage sludge as produced by the steps of (1) dewatering sewage sludge to produce an aqueous slurry having a solids content of about 10 to 25 wt. %; (2) pretreating said aqueous slurry of sewage sludge to improve its slurrying characteristics by one or a combination of (a) heating, (b) hydrothermal treatment, and (c) heating, mixing and shearing; and (3) mixing the following materials together at a temperature in the range of about ambient to 400.degree. F. to produce a pumpable aqueous slurry having a solids content in the range of about 30 to 65 wt. %: (a) pretreated aqueous slurry of sewage sludge; (b) a nonionic water soluble alkoxylated alkylphenol additive; and (c) sewage sludge-containing material and/or solid carbonaceous fuel-containing material to increase the solids loading.
    Type: Grant
    Filed: May 20, 1991
    Date of Patent: October 18, 1994
    Assignee: Texaco Inc.
    Inventors: Motasimur R. Khan, Christine C. Albert
  • Patent number: 5354345
    Abstract: A process for thermochemical beneficiation of carbonaceous solids including a fraction of particles of a size less than 1/4 inch across is provided. The process includes steps of providing a reactor vessel including therein a retaining structure operably positioned to separate a portion of carbonaceous solids from a wall of the reactor vessel, with a free standing liquids region therebetween. The process includes providing a portion of carbonaceous solids piled above an uppermost liquid level of process liquid within the reactor vessel. The disclosure also provides a preferred reactor arrangement for conduct of the process.
    Type: Grant
    Filed: February 22, 1993
    Date of Patent: October 11, 1994
    Assignee: Minnesota Power and Light
    Inventor: George R. Nehls, Jr.
  • Patent number: 5292442
    Abstract: A process for disposing of sanitary sewage sludge by producing a pumpable slurry of sewage sludge with or without solid carbonaceous fuel and burning said slurry as fuel in a partial oxidation gas generator, furnace, or boiler. The aqueous slurry of sewage sludge is concentrated by removing water by means of a conventional belt filter press, centrifuge, or hydroclone. The dewatered slurry of sewage sludge is heated by direct contact with steam while air and organic vapors are simultaneously removed, to reduce the pressure in the system; hydrothermally treated in two steps with indirect and direct heat exchange with steam; dewatered by flash evaporation and centrifuging; and burned with or without admixture with solid carbonaceous fuel in a partial oxidation gasifier, furnace, boiler, or incinerator to produce synthesis gas or a hot raw effluent gas stream. In a preferred embodiment, the effluent gas stream is cleaned and purified and non-contaminating ash and slag are separated.
    Type: Grant
    Filed: October 1, 1992
    Date of Patent: March 8, 1994
    Assignee: Texaco Inc.
    Inventors: Motasimur R. Khan, Harvey D. Schindler, Christine C. Albert, Stephan J. DeCanio
  • Patent number: 5290327
    Abstract: A method for generating, from refuse or refuse in combination with coal, a fuel gas suited for public utility purposes wherein refuse and coal can be introduced into the process in any proportion one to the other. The method provides the steps of subjecting the refuse to allothermal low-temperature carbonization, if desired in combination with coal, burning the gasification residue, purifying the crude gas and conditioning the pure gas for public utility purposes.
    Type: Grant
    Filed: September 30, 1991
    Date of Patent: March 1, 1994
    Inventor: Gottfried Rossle
  • Patent number: 5273556
    Abstract: A process for disposing of sewage sludge by heating and shearing an aqueous mixture of sewage sludge in a tubular-shaped processing means containing a plurality of rotating agitators to produce a pumpable aqueous slurry of sewage sludge. The aqueous slurry of sewage sludge is mixed with solid carbonaceous fuel or an aqueous slurry of solid carbonaceous fuel to produce a pumpable aqueous slurry of sewage sludge and solid carbonaceous fuel. The aqueous slurry of sewage sludge and solid carbonaceous fuel is heated in a first steam jacketed rotary disc mixing-heating means. Alternately, first and second hoppers are filled with said heated aqueous slurry of sewage sludge and solid carbonaceous fuel and cycled between a second steam jacketed rotary disc mixing-heating means; wherein while one hopper is being filled the contents in the other hopper are being dewatered. The thickened pumpable slurry is burned in a partial oxidation gasifier, furnace, boiler, or incinerator to produce a hot effluent gas steam.
    Type: Grant
    Filed: March 30, 1992
    Date of Patent: December 28, 1993
    Assignee: Texaco Inc.
    Inventors: Matthew A. McMahon, Ronald J. McKeon, Robert F. Heyl, Motasimur R. Khan, Kenneth W. McKenzie, Enrique F. Depaz
  • Patent number: 5266085
    Abstract: A process for disposing of sewage sludge comprising the steps of, (1) dewatering the sewage sludge to produce an aqueous slurry of sewage sludge having a solids content of about 10 to 30 wt. %; (2) simultaneously heating and shearing said dewatered sewage sludge at about 150.degree. F. to 210.degree. F. in the absence of air for 0.5 seconds to 60 minutes while being continuously passed through a tubular-shaped processing means containing a plurality of rotating agitators, thereby producing a pumpable slurry having a viscosity of less than about 2000 centipoise; (3) dewatering the sewage sludge if necessary; (4) mixing at a temperature in the range of about ambient to 180.degree. F. in a ribbon or in-line static mixer the slurry of sewage sludge from (2) and/or (3) with a supplemental solid carbonaceous fuel e.g. coal and/or petroleum-coke to produce a pumpable aqueous slurry of sewage sludge and supplemental fuel having a solids content in the range of about 50 to 60 wt.
    Type: Grant
    Filed: November 23, 1992
    Date of Patent: November 30, 1993
    Assignee: Texaco Inc.
    Inventors: Matthew A. McMahon, Motasimur R. Khan, Robert F. Heyl, Ronald J. McKeon, Kenneth W. McKenzie
  • Patent number: 5264009
    Abstract: A process for disposing of sanitary sewage sludge by producing a pumpable slurry of sewage sludge with or without solid carbonaceous fuel and burning said slurry as fuel in a partial oxidation gas generator, furnace, or boiler. The aqueous slurry of sewage sludge is concentrated by removing water by means of a conventional belt filter press, centrifuge, or hydroclone. The dewatered slurry of sewage sludge is preheated and sheared; hydrothermally treated; and its solids content increased. A chelating agent, for example an aminopolycarboxylic acid or a hydrocarboxylic acid is mixed with the aqueous slurry of sewage sludge during the preheating and shearing step and/or the step for increasing its solids content. By means of the subject process, the viscosity of the slurry of sewage sludge with or without solid carbonaceous fuel is reduced and coagulation is suppressed.
    Type: Grant
    Filed: September 1, 1992
    Date of Patent: November 23, 1993
    Assignee: Texaco Inc.
    Inventor: Motasimur R. Khan
  • Patent number: 5234469
    Abstract: A process for disposing of sewage sludge comprising the steps of, (1) dewatering the sewage sludge to produce an aqueous slurry of sewage sludge having a solids content of about 10 to 50 wt. %; (2) heating and mildly shearing said dewatered sewage sludge at about 150.degree. F. to 210.degree. F. in the absence of air for 3 seconds to 60 minutes by a rotor/mixer at a speed of about 15 to 1000 r.p.m., thereby producing a pumpable slurry having a viscosity of less than about 2500 centipoise; (3) mixing at a temperature in the range of about ambient to 200.degree. F. the slurry of sewage sludge from (2) with a supplemental fuel to produce a pumpable slurry of sewage sludge and supplemental fuel having a solids content in the range of about 50 to 65 wt. % and a higher heating value in the range of about 6,000 to 18,000 BTU/LB; and (4) burning said pumpable slurry from (3) in a partial oxidation gasifier, furnace, boiler, or incinerator to produce an effluent gas stream.
    Type: Grant
    Filed: June 28, 1991
    Date of Patent: August 10, 1993
    Assignee: Texaco Inc.
    Inventors: Motasimur R. Khan, Matthew A. McMahon, Christine C. Albert, Ronald J. McKeon, Stephen J. DeCanio
  • Patent number: 5234468
    Abstract: A process for disposing of sewage sludge comprising the steps of, (1) dewatering the sewage sludge to produce amorphous sewage sludge having a solids content of about 28 to 50 wt. %; (2) heating said amorphous sewage sludge at about 150.degree. F. to 510.degree. F. in the absence of air for 3 seconds to 60 minutes and mildly shearing the sewage sludge, thereby producing a pumpable feed slurry of sewage sludge having a viscosity in the range of about 400 to 1500 centipoise and a higher heating value in the range of about 5000 to 9500 BTU/LB; and (3) burning said pumpable slurry from (2) in a partial oxidation gasifier, furnace, boiler, or incinerator to produce an effluent gas stream. In one embodiment, the effluent gas stream is cleaned and purified and non-contaminating fly-ash and slag are separated. The fly-ash may be mixed with the sewage sludge in the process to facilitate separation of water during pressing and to encapsulate the non-combustible materials in the sewage sludge.
    Type: Grant
    Filed: June 28, 1991
    Date of Patent: August 10, 1993
    Assignee: Texaco Inc.
    Inventor: Motasimur R. Khan
  • Patent number: 5230211
    Abstract: An improved process for the low-cost disposal of noxious municipal sewage sludge in a safe way without polluting the environment. In the process, a portion of a stream of dewatered sewage sludge having a solids content in the range of about 17 to 40 wt.% is dried to produce dried sewage sludge having a solids content in the range of about 75 to 99 wt.%. The dried sewage sludge is ground to a small particle size. A pumpable aqueous feed slurry having a solids content in the range of about 45 to 70 wt.% is produced comprising (a) solid carbonaceous fuel, (b) ground dried sewage sludge, and (c) sheared and/or unsheared dewatered sewage sludge. The parts by weight of (a):(b):(c) are respectively in the range of about 3 to 8:0.5 to 2:0.5 to 2, and preferably 6:1:1. The aqueous feed slurry is gasified in a free-flow partial oxidation gas generator. Synthesis gas, reducing gas or fuel gas is produced, Ash and slag are separated from the gas stream and safely disposed.
    Type: Grant
    Filed: April 15, 1991
    Date of Patent: July 27, 1993
    Assignee: Texaco Inc.
    Inventors: Matthew A. McMahon, Michael C. Martin, Kenneth W. McKenzie
  • Patent number: 5211724
    Abstract: An improved process for the low-cost disposal of noxious sewage sludge in a safe way without polluting the environment. In the process, sewage sludge having a solids content of about 0.5 to 20 wt.% is concentrated by pressing in a belt filter press, optionally followed by pressing in a high intensity press. It was unexpectedly found that the morphology of the resulting dewatered sewage sludge is changed by such mechanical treatment so that slurries with higher concentrations of solids are achieved. The dewatered sewage sludge is heated, flash evaporated and/or centrifuged, and mixed with a supplemental fuel e.g., liquid hydrocarbonaceous and/or solid carbonaceous fuel to produce a pumpable fuel slurry having a total solids content in the range of about 50 to 70 wt.% and comprising about 10 to 40 wt.% dewatered sewage sludge and having a higher heating value in the range of about 5,000 to 14,000 BTU/Lb.
    Type: Grant
    Filed: April 15, 1991
    Date of Patent: May 18, 1993
    Assignee: Texaco, Inc.
    Inventors: Motasimur R. Khan, Ronald J. McKeon
  • Patent number: 5211723
    Abstract: This invention relates to a novel pumpable sewage sludge fuel and process for burning it. An aqueous slurry of sewage sludge is dewatered and dried to a solids content in the range of about 50 to 99 wt. % in a drying zone in the absence of free-oxygen containing gas but while in contact with a gaseous material selected from the group consisting of N.sub.2, CO.sub.2, H.sub.2, CO, and mixtures thereof. The dried sewage sludge is mixed with a supplementary fuel from the group consisting of solid carbonaceous fuel, liquid hydrocarbonaceous fuel, mixtures thereof, and optionally with water to produce a pumpable slurry fuel feedstream having a solids content in the range of about 50 to 65 wt. % and a higher heating value of at least about 6,000 Btu/lb. The slurry fuel feedstream may be burned in a partial oxidation gasifier, furnace, boiler, or incinerator.
    Type: Grant
    Filed: September 19, 1991
    Date of Patent: May 18, 1993
    Assignee: Texaco Inc.
    Inventor: Motasimur R. Khan
  • Patent number: 5188740
    Abstract: A process for disposing of sanitary sewage sludge by producing a pumpable slurry of sewage sludge and low grade solid carbonaceous fuel and burning said slurry as fuel in a partial oxidation gas generator, furnace, or boiler. The aqueous slurry of sewage sludge is concentrated by removing water by means of a conventional belt filter press or presses. Prior to and/or immediately after said concentrating step particles of low grade solid carbonaceous fuel e.g. lignitic coal, peat, wood and cellulose-containing materials are mixed with the slurry of sewage sludge. The dewatered slurry of sewage sludge and low grade solid carbonaceous fuel is hydrothermally treated in three stages and excess water is separated by flash evaporization and/or centrifuging.
    Type: Grant
    Filed: December 2, 1991
    Date of Patent: February 23, 1993
    Assignee: Texaco Inc.
    Inventor: Motasimur R. Khan
  • Patent number: 5188739
    Abstract: A process for disposing of sanitary sewage sludge by producing a pumpable slurry of sewage sludge and solid carbonaceous fuel e.g. coal, petroleum coke, rubber. The slurry is burned as a fuel in a partial oxidation gas generator, furnace, or boiler. In the process, an aqueous slurry of sewage sludge is concentrated by removing water by means of a conventional belt filter press or presses. The dewatered slurry of sewage sludge is hydrothermally treated and cooled and depressurized. The viscosity of the slurry of sewage sludge is reduced to less than about 2000 centipoise by shearing. The sheared sewage sludge is then ground together with a solid carbonaceous fuel to produce a pumpable slurry which is burned with a free-oxygen containing gas in a partial oxidation gasifier, furnace, boiler, or incinerator to produce a hot raw effluent gas stream. In a preferred embodiment, the effluent gas stream is cleaned and purified and non-contaminating ash and slag are separated.
    Type: Grant
    Filed: December 2, 1991
    Date of Patent: February 23, 1993
    Assignee: Texaco Inc.
    Inventors: Motasimur R. Khan, Richard B. Zang, Christine C. Albert
  • Patent number: 5188741
    Abstract: A process for treating sanitary sewage sludge to achieve increased solids, decreased viscosity, and a reduction of pathogens. The aqueous slurry of sewage sludge having a solids content in the range of about 3 to 35 wt. % is simultaneously conveyed and preheated, mascerated, heated in an heat exchanger, hydrothermally treated in a closed vessel under a blanket of nitrogen at about 500.degree. F. and a pressure of about 750 psig and above the vapor pressure of water at that temperature, dewatered and cooled in a first multi-step flash evaporation zone where the pressure is dropped in three steps from about 750 psig to about 50 psig and then in a second flash evaporation zone the pressure is dropped to about 25 psig, cooling and condensing the vapor from said first and second flash evaporation zones, and removing a dewatered pumpable slurry of sewage sludge product having a solids content in the range of about 5 to 50 wt. % and a reduced amount of pathogens.
    Type: Grant
    Filed: April 1, 1992
    Date of Patent: February 23, 1993
    Assignee: Texaco Inc.
    Inventors: Richard B. Zang, Motasimur R. Khan
  • Patent number: 5114541
    Abstract: A process for producing solid, liquid and gaseous fuels comprising the use of an organic starting material selected from a bio-mass of microbial, vegetable or animal origin and sediments or garbage containing organic material, heating said organic material under the exclusion of air slowly to a conversion temperature of 200.degree. to 600.degree. C., conducting the gases and vapors escaping during the heating through suitable gas and liquid separators, maintaining the conversion temperature until the development of gases and vapors has substantially ceased, and isolating the solid conversion residues and the separated gases and liquids.
    Type: Grant
    Filed: May 13, 1991
    Date of Patent: May 19, 1992
    Inventor: Ernst Bayer
  • Patent number: 5072675
    Abstract: A process for the destruction of waste including the steps of passing an organic waste into a chamber, pumping an inert gas into the chamber until the pressure within the chamber is at least 10,000 p.s.i., heating the chamber to a temperature in excess of 300.degree. F., dissociating the organic waste into its gaseous constituents, and passing the gaseous constituents from the chamber. The chamber is filled with an inert gas so as to displace oxygen from the chamber. The pressurized gaseous constituents are delivered to a turbine so as to actuate the turbine and to generate electricity therefrom. The gaseous constituents pass from the turbine into a boiler. An oxygen-containing gas is mixed with the gaseous constituents within the boiler so as to produce pressurized steam. This pressurized steam is passed to a turbine so as to produce electricity. The inert gas is argon.
    Type: Grant
    Filed: April 15, 1991
    Date of Patent: December 17, 1991
    Inventor: Benjamin P. Fowler
  • Patent number: 5050511
    Abstract: A system for the destruction of organic waste material such as halogenated organic compounds, and related matter. In one embodiment the waste material is reduced with a gaseous reducing agent such as hydrogen above about 600.degree. C., the gaseous products are condensed and cooled in the presence of an aqueous mist at about 5.degree. C., and condensed organic and aqueous material is collected and the aqueous portion recycled into the condensing and cooling steps. In another embodiment, where acid gases (for example, hydrogen halides) are produced during reduction, the gaseous products are condensed in the presence of aqueous mist at about 85.degree. C. and a major portion of the aqueous mist condenses as acidic water which is collected and neutralized. Remaining gaseous components are then cooled to about 5.degree. C. as in the previous embodiment. In further embodiments, the remaining uncondensed gaseous products are oxidized with a gaseous oxidizing agent at a temperature above about 1000.degree. C.
    Type: Grant
    Filed: December 21, 1990
    Date of Patent: September 24, 1991
    Assignee: 655901 Ontario Inc.
    Inventors: Douglas J. Hallett, Kelvin R. Campbell
  • Patent number: 5046436
    Abstract: An apparatus for the preheating of liquid waste having a heated sealed container, a liquid waste tank, a jacket positioned around the sealed container so as to form a heat exchange region between the interior of the jacket and the exterior of the sealed container, and an injector for transmitting a heated liquid waste from the tank into the interior of the sealed container. An inert gas container is connected to the waste tank so as to pass argon gas for displacing the oxygen from the interior of the liquid waste tank. An insulating layer is formed around the exterior of the sealed container and the waste tank. Suitable conduits connect the waste tank with the heat exchange region of the sealed container. A storage vessel is in valved relationship with the liquid waste tank. Suitable pumping is provided so as to transmit the liquid waste into the heat exchange region and back to the liquid waste tank.
    Type: Grant
    Filed: October 15, 1990
    Date of Patent: September 10, 1991
    Inventor: Benjamin P. Fowler
  • Patent number: 5006249
    Abstract: Waste water comprising organic pollutants, a Group II A metal component and a high concentration of an alkali metal component, such as produced water, is treated with an acclimated biomass of anaerobic microorganisms to decompose the organic pollutants to carbon dioxide and methane.
    Type: Grant
    Filed: December 29, 1988
    Date of Patent: April 9, 1991
    Assignee: Exxon Research and Engineering Company
    Inventors: George A. Green, Stanislaus A. Kaczmarek
  • Patent number: 4992173
    Abstract: A method is for operating a boiler to heat a bioreactor with gases produced from the bioreactor, while supplying excessive hot water to outside of a system. In the method, the boiler is operated to turn on and off depending upon temperature of a hot water tank when a level of a gas holder is higher than an intermediate level H.sub.1. Hot water is unconditionally supplied to the outside of the system when the level of the gas holder is higher than a high level H.sub.2, and hot water is supplied to the outside when temperature of the hot water tank is higher than an intermediate temperature L.sub.1 and the level of the gas holder is between the high level H.sub.2 and the intermediate level H.sub.1. The supply of the hot water is stopped when the level of the gas holder is less than the intermediate level H.sub.1.
    Type: Grant
    Filed: May 18, 1990
    Date of Patent: February 12, 1991
    Assignee: NGK Insulators, Ltd.
    Inventors: Keiji Matsuoka, Yuzo Okamoto, Isao Niwa
  • Patent number: 4983296
    Abstract: Municipal sanitary sewage sludge is disposed of by an improved partial oxidation process without polluting the environment. Aqueous slurries of sewage sludge are upgraded by hydrothermal treatment, preferably while being sheared, concentrated, and then mixed with a supplemental fuel, preferably coal. A pumpable aqueous slurry of sewage sludge-coal and/or petroleum coke is thereby produced having a greater total solids and heat content (HHV) as well as containing an increased amount of sewage sludge for reacting with free-oxygen containing gas in a free-flow partial oxidation gas generator. Hot quench water or steam produced by cooling the hot raw effluent stream of synthesis gas, reducing gas or fuel gas from the gasifier may provide heat for the hydrothermal step.
    Type: Grant
    Filed: August 3, 1989
    Date of Patent: January 8, 1991
    Assignee: Texaco Inc.
    Inventors: Matthew A. McMahon, Robert M. Suggitt, Ronald J. McKeon, Albert Brent
  • Patent number: 4950309
    Abstract: Toxic refractory organic substances are decomposed by reaction with oxygen and steam at a temperature in the range of 2500.degree. F. to 3200.degree. F. Such toxic refractory organic compounds as PCB's, may be completely destroyed without contamination of the environment.
    Type: Grant
    Filed: October 14, 1988
    Date of Patent: August 21, 1990
    Assignee: Dynecology Incorporated
    Inventor: Helmut W. Schulz
  • Patent number: 4934286
    Abstract: A process for the disposal of waste comprising the steps of passing a waste into a sealed container, purging the sealed container of oxygen, heating the interior of the sealed container to a temperature of greater than 2,700.degree. F. so as to convert the waste into a gas, and transmitting the gas into a storage vessel. An inert gas is introduced into the interior of the sealed container so as to displace oxygen from within the sealed container. The inert gas is ideally nitrogen. The interior of the sealed container is heated by induction heating. The gas is transferred through a water filter so as to remove the carbon component of the gas. The water filtered gas is then passed through a sodium hydroxide filter so as to remove the chlorine component of the gas. The gas is then sieved so as to separate the various gaseous components for individual storage.
    Type: Grant
    Filed: August 24, 1989
    Date of Patent: June 19, 1990
    Inventor: Benjamin P. Fowler
  • Patent number: 4933086
    Abstract: Municipal sanitary sewage sludge is disposed of by an improved partial oxidation process without polluting the environment. Aqueous slurries of sewage sludge are upgraded by being sheared without heating, concentrated if necessary, and then mixed with a supplemental fuel, preferably coal. In one embodiment, the aqueous slurry of sewage sludge and the supplemental coal and/or petroleum coke are introduced into a shearing mixer for simultaneous shearing and mixing together. A pumpable aqueous slurry of sewage sludge-coal and/or petroleum coke is thereby produced having an increased amount of total solids and an increased heat content (HHV) as well as containing an increased amount of sewage sludge for reacting with free-oxygen containing gas in a free-flow partial oxidation gas generator. Hot quench water or steam produced by cooling the hot raw effluent stream of synthesis gas, reducing gas or fuel gas from the gasifier may provide heat for indirect heat exchange with other streams in the process.
    Type: Grant
    Filed: August 3, 1989
    Date of Patent: June 12, 1990
    Assignee: Texaco Inc.
    Inventors: Matthew A. McMahon, Robert M. Suggitt, Ronald J. McKeon, Albert Brent
  • Patent number: 4861519
    Abstract: The invention relates to a method and apparatus for the reduction in the quantity of low activity organic wastes from nuclear power plants. This is accomplished using anaerobic fermentation in a bioreactor. The waste from the nuclear power plant is subjected to a pretreatment such as comminution and suspension, hydrolysis and/or physical dispersion, such as by a irradiation, heat treatment or the equivalent. The pretreated waste is subjected to anaerobic decomposition in a bioreactor, the anaerobic decomposition taking place in two stages, namely an acid stage and a methane stage. The gases produced in the decomposition process are conducted from the methane stage to a gas burning stage and the undecomposed waste is removed, concentrated and packed in barrels or the like for storage.
    Type: Grant
    Filed: March 25, 1988
    Date of Patent: August 29, 1989
    Assignee: Imatran Voima Oy
    Inventors: Esko Tusa, Raimo Maatta, Antti Ruuskanen
  • Patent number: 4851600
    Abstract: The invention relates to a process for the destruction of waste, like biologically difficult to degrade halogen-, nitrogen-, sulphur-, and/or oxygen containing compounds by thermal hydrogenolysis. The waste materials are heated together with an excess hydrogen and/or hydrogen donor during 1 to 10 sec. to a temperature between 700.degree.-1220.degree. C., followed by quenching the gaseous effluent of the reaction and separating it in a hydrocarbon and hydrogen containing phase and a hydrogen halogenide(s) nitrogen-, sulphur-, and/or oxygen containing compounds containing phase.Preferably the hydrogenolysis is performed in two steps, first during 1-10 sec. at 700.degree.-900.degree. C. and second during 1-10 sec. at 850.degree.-1200.degree. C.
    Type: Grant
    Filed: August 28, 1985
    Date of Patent: July 25, 1989
    Assignee: Rijksuniversiteit Leiden
    Inventor: Robert Louw
  • Patent number: 4848249
    Abstract: A system is disclosed for converting unconditioned biomass, such as cotton gin trash, into usable energy. This is accomplished by gasifying the biomass, removing the particulate char from the combustible gas using cyclonic separators, burning the gas, and using the heat to generate steam. Two stage combustion helps minimize NO.sub.x formation.
    Type: Grant
    Filed: November 30, 1987
    Date of Patent: July 18, 1989
    Assignee: Texas A&M University
    Inventors: Wayne A. LePori, Calvin B. Parnell
  • Patent number: 4849108
    Abstract: A process for purifying waste water resulting from the manufacture of chemo- and/or thermomechanical pulp, which comprises subjecting the waste water to at least the following sequence of steps:sedimentation of coarser constituents (4);cooling (6);detoxification (7);anaerobic hydrolysis and preacidification (10) with addition of nutrient salts and readjustment of the redox potential;production of methane in a methane reactor (11);aerobic purification and separation of biologic sludge (12; 13), which is at least partly recycled to the detoxification step (7), in which process aerobic sludge is separated prior to the anaerobic hydrolysis step (10).
    Type: Grant
    Filed: November 6, 1987
    Date of Patent: July 18, 1989
    Assignee: KNP Papier B.V.
    Inventors: Etienne F. de Wilde, Hubertus W. Broens
  • Patent number: 4793855
    Abstract: A process for the gasification of sewage sludge or other carbon-containing waste materials in a gasifier (1) is described. A solid fuel and oxygen-containing gas are also fed into said gasifier. The residues formed during gasification collect at the bottom of the gasifier in the form of molten slag. Gasification takes place in a fluidized bed (9) formed above the slag bath and constituted by the dried sewage sludge or waste materials, the solid fuel, the oxygen-containing gas and the gasification gas. The gas produced in the gasifier can be used for power generation or as a reducing gas for iron ore. Sponge iron can simultaneously be melted in the gasifier and reduced to pig iron.
    Type: Grant
    Filed: January 30, 1987
    Date of Patent: December 27, 1988
    Inventor: Rolf Hauk
  • Patent number: 4781836
    Abstract: An improved process for the biomethanation of an organic substrate includes treating the substrate in a first reactor to form organic acid anions, passing an aqueous preparation containing dissolved organic anions through an anion exchanger so that the organic acid anions are adsorbed and separated from the remainder of the aqueous preparation, desorbing the organic acid anions and passing the desorbed acids to a second reactor containing methanogenic bacteria which convert the acids to methane. In a preferred embodiment, a bicarbonate solution is produced in the second reactor and it is used to desorb the organic acid anions and regenerate the anion exchanger into the bicarbonate form.
    Type: Grant
    Filed: May 16, 1986
    Date of Patent: November 1, 1988
    Assignee: Michigan Biotechnology Institute
    Inventors: Jurgen Thiele, Joseph G. Zeikus
  • Patent number: 4769149
    Abstract: A process for recovery of energy from waste and residues is disclosed. The residues, after sieving, are subjected to bacterial digestion in a methanization reactor and the solid phase of the digestate is then subjected to incineration in a furnace supplying a heat recuperator, the furnace being supplied with complementary combustible by the methane coming from the digester, while the circuit of the fumes downstream of the recuperator is used for heating by at least one secondary circuit, the magma in the course of treatment in the digester and/or the sludge separated from the digestate before recycling thereof towards the digester.
    Type: Grant
    Filed: August 4, 1987
    Date of Patent: September 6, 1988
    Assignee: Propiorga
    Inventors: Bernard Nobilet, Michel Bonhomme, Philippe Desplat
  • Patent number: 4735724
    Abstract: A non-mixed vertical tower anaerobic digester and anaerobic digestion process provides passive concentration of biodegradable feed solids and microorganisms in an upper portion of a continuous digester volume and effluent withdrawal from the middle to bottom portion of the digester, resulting in increased solids retention times, reduced hydraulic retention times, and enhanced bioconversion efficiency. In addition, due to passive concentration of solids, the non-mixed anaerobic digester accommodates high solids loadings and provides separation of microbial phases within the continuous digester volume to achieve substantially complete bioconversion of biodegradable feedstock components.
    Type: Grant
    Filed: July 30, 1986
    Date of Patent: April 5, 1988
    Assignee: Gas Research Institute
    Inventors: David P. Chynoweth, Vipul J. Srivastava, Richard Biljetina, Thomas D. Hayes
  • Patent number: 4722741
    Abstract: An improved anaerobic digestion process is provided to enhance the methane content of product gas so that no further processing may be required for utilization as high quality, high Btu gas comprising greater than 90 percent methane. Operating conditions of lowered carbon dioxide influent concentration to the methane production digester and operation of the methane production digester under pressurization achieve high conversion efficiency rates and high methane content product gas. The carbon dioxide produced during the anaerobic digestion may be physically and chemically separated and removed thereby reducing the carbon dioxide content of the product gas.
    Type: Grant
    Filed: March 11, 1985
    Date of Patent: February 2, 1988
    Assignee: Gas Research Institute
    Inventors: Thomas D. Hayes, H. Ronald Isaacson, James R. Frank
  • Patent number: 4696746
    Abstract: A two phase anaerobic digestion process for production of methane from organic carbonaceous material in which an active acid forming microbial population is maintained in a first acid forming digestion phase and an active methane forming microbial population is maintained in a second methane forming digestion phase, the liquid effluent from the acid forming digestion phase being passed to a first methane forming digester and gaseous product from the acid forming digestion phase being passed to a second separated methane forming digester for production of methane in the first and second methane forming digesters of the methane forming digestion phase. The two separated methane digestion phases provide increased overall methane production.
    Type: Grant
    Filed: October 30, 1984
    Date of Patent: September 29, 1987
    Assignee: Institute of Gas Technology
    Inventors: Sambhunath Ghosh, David P. Chynoweth, Paul B. Tarman