Patents by Inventor Richard R. Davison

Richard R. Davison has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20100248318
    Abstract: In one embodiment, the disclosure includes a method of biomass conversion including fermenting biomass to produce a carboxylic acid or carboxylate salt and hydrogen gas, recovering the hydrogen gas, and converting the carboxylic acid or carboxylate salt to an alcohol using the hydrogen gas. In one embodiment, the hydrogen produced by biomass conversion may be converted to an acetate. Another embodiment relates to a biomass conversion system. The system may include: a fermentation unit for fermentation of biomass to a carboxylic acid or carboxylate salt in a fermentation broth and for production of a carbon dioxide and hydrogen gas stream, an extraction unit for extracting the carboxylic acid or carboxylate salt from the fermentation broth, a gas extraction unit for separation of the hydrogen gas and the carbon dioxide, and a production unit for production of an alcohol from the carboxylic acid or carboxylate salt using the hydrogen gas.
    Type: Application
    Filed: June 7, 2010
    Publication date: September 30, 2010
    Applicant: TEXAS A&M UNIVERSITY SYSTEMS
    Inventors: Cesar B. Granda, Mark T. Holtzapple, Richard R. Davison
  • Publication number: 20100152485
    Abstract: In accordance with the teachings of the present invention, a system and method converting biomass into useful chemicals are provided. In a particular embodiment, the method includes fermenting biomass in one or more fermentors to produce a fermentation broth comprising ammonium carboxylate salts, the fermentors containing an ammonium carbonate or ammonium bicarbonate buffer. The method further includes reacting the ammonium carboxylate salts from the fermentors with a high-molecular-weight amine to produce amine carboxylate salt, and thermally cracking the amine carboxylate salt to produce carboxylic acid. In another embodiment, the ammonium carboxylate salts from the fermentors may be reacted with a low-molecular-weight amine to produce a low-molecular-weight-amine carboxylate salt.
    Type: Application
    Filed: February 3, 2010
    Publication date: June 17, 2010
    Applicant: TEXAS A&M UNIVERSITY SYSTEM
    Inventors: Mark T. Holtzapple, Richard R. Davison, Cesar B. Granda, Frank K. Agbogbo, Zhihong Fu
  • Publication number: 20080176301
    Abstract: In one embodiment, the disclosure includes a method of biomass conversion including fermenting biomass to produce a carboxylic acid or carboxylate salt and hydrogen gas, recovering the hydrogen gas, and converting the carboxylic acid or carboxylate salt to an alcohol using the hydrogen gas. In one embodiment, the hydrogen produced by biomass conversion may be converted to an acetate. Another embodiment relates to a biomass conversion system. The system may include: a fermentation unit for fermentation of biomass to a carboxylic acid or carboxylate salt in a fermentation broth and for production of a carbon dioxide and hydrogen gas stream, an extraction unit for extracting the carboxylic acid or carboxylate salt from the fermentation broth, a gas extraction unit for separation of the hydrogen gas and the carbon dioxide, and a production unit for production of an alcohol from the carboxylic acid or carboxylate salt using the hydrogen gas.
    Type: Application
    Filed: November 30, 2007
    Publication date: July 24, 2008
    Inventors: Cesar B Granda, Mark T. Holtzapple, Richard R. Davison
  • Patent number: 6478965
    Abstract: Dilute solutions of fermentation sales may be concentrated by extracting water using low-miscibility, low-molecular-weight secondary and tertiary amines, e.g. triethylamine (TEA), diisopropyl amine (DIA), N,N-diethylmethylamine (DEMA), and mixtures thereof. At 30° C.-55° C., which corresponds to typical fermentation temperatures, these low-molecular-weight amines or their mixtures, can extract large amounts of water from dilute aqueous solutions containing fermentation salts. Thus, dilute fermentation salt solutions can be concentrated by selectively removing water. At these low temperatures, the amine phase contains 20-35% water and a much reduced quantity of fermentation salt. When the temperature is raised, water phases out of the amine, allowing the amine to be recycled and reused to extract additional water. Using this approach, about 82.
    Type: Grant
    Filed: November 16, 1999
    Date of Patent: November 12, 2002
    Assignee: The Texas A&M University System
    Inventors: Mark T. Holtzapple, Richard R. Davison, Torsten Luettich
  • Patent number: 6395926
    Abstract: The invention provides a method for recovering low-boiling acids from a concentrated solution of the calcium salt of the acid by treating the concentrated solution of calcium salts of the low-boiling acids with a high molecular weight tertiary amine and carbon dioxide.
    Type: Grant
    Filed: June 15, 2001
    Date of Patent: May 28, 2002
    Assignee: Texas A&M University System
    Inventors: Mark T. Holtzapple, Richard R. Davison
  • Publication number: 20020038058
    Abstract: This invention provides a method for thermally converting volatile fatty acid (VFA) salts to ketones by mixing dry calcium salts of VFAs with hot heat transfer agent in an evacuated container, thereby causing thermal decomposition of the calcium salts of VFAs to form ketone-containing vapor and calcium carbonate; and separating the ketone-containing vapor from the calcium carbonate and heat transfer agent by condensing a mixture of ketones from the ketone-containing vapor. This invention also provides a process for conversion of VFA salts, produced by anaerobic fermentation of cellulosic biomass, into liquid fuels, volatile fatty acids, aldehydes, alcohols, and lactic acid.
    Type: Application
    Filed: June 15, 2001
    Publication date: March 28, 2002
    Inventors: Mark T. Holtzapple, Richard R. Davison
  • Patent number: 6262313
    Abstract: This invention provides a method for thermally converting volatile fatty acid (VFA) salts to ketones by mixing dry calcium salts of VFAs with hot heat transfer agent in an evacuated container, thereby causing thermal decomposition of the calcium salts of VFAs to form ketone-containing vapor and calcium carbonate; and separating the ketone-containing vapor from the calcium carbonate and heat transfer agent by condensing a mixture of ketones from the ketone-containing vapor. This invention also provides a process for conversion of VFA salts, produced by anaerobic fermentation of cellulosic biomass, into liquid fuels, volatile fatty acids, aldehydes, alcohols, and lactic acid.
    Type: Grant
    Filed: December 22, 1999
    Date of Patent: July 17, 2001
    Assignee: Texas A&M University System
    Inventors: Mark T. Holtzapple, Richard R. Davison
  • Patent number: 6043392
    Abstract: This invention provides a method for thermally converting volatile fatty acid (VFA) salts to ketones by mixing dry calcium salts of VFAs with hot heat transfer agent in an evacuated container, thereby causing thermal decomposition of the calcium salts of VFAs to form ketone-containing vapor and calcium carbonate; and separating the ketone-containing vapor from the calcium carbonate and heat transfer agent by condensing a mixture of ketones from the ketone-containing vapor. This invention also provides a process for conversion of VFA salts, produced by anaerobic fermentation of cellulosic biomass, into liquid fuels, volatile fatty acids, aldehydes, alcohols, and lactic acid.
    Type: Grant
    Filed: June 30, 1997
    Date of Patent: March 28, 2000
    Assignee: Texas A&M University System
    Inventors: Mark T. Holtzapple, Richard R. Davison
  • Patent number: 5986133
    Abstract: Dilute solutions of fermentation sales may be concentrated by extracting water using low-miscibility, low-molecular-weight secondary and tertiary amines, e.g. triethylamine (TEA), diisopropyl amine (DIA), N,N-diethylmethylamine (DEMA), and mixtures thereof. At 30.degree. C.-55.degree. C., which corresponds to typical fermentation temperatures, these low-molecular-weight amines or their mixtures, can extract large amounts of water from dilute aqueous solutions containing fermentation salts. Thus, dilute fermentation salt solutions can be concentrated by selectively removing water. At these low temperatures, the amine phase contains 20-35% water and a much reduced quantity of fermentation salt. When the temperature is raised, water phases out of the amine, allowing the amine to be recycled and reused to extract additional water. Using this approach, about 82.
    Type: Grant
    Filed: June 30, 1997
    Date of Patent: November 16, 1999
    Assignee: The Texas A&M University System
    Inventors: Mark T. Holtzapple, Richard R. Davison, Torsten Luettich
  • Patent number: 5969189
    Abstract: This invention provides a method for thermally converting volatile fatty acid (VFA) salts to ketones by mixing dry calcium salts of VFAs with hot heat transfer agent in an evacuated container, thereby causing thermal decomposition of the calcium salts of VFAs to form ketone-containing vapor and calcium carbonate; and separating the ketone-containing vapor from the calcium carbonate and heat transfer agent by condensing a mixture of ketones from the ketone-containing vapor.
    Type: Grant
    Filed: June 30, 1997
    Date of Patent: October 19, 1999
    Assignee: The Texas A&M University System
    Inventors: Mark T. Holtzapple, Richard R. Davison
  • Patent number: 5865898
    Abstract: The invention is directed to methods for the pretreatment of a lignocellulose-containing biomass. Pretreatment comprises the addition of calcium hydroxide and water to the biomass to form a mixture, and subjecting the mixture to relatively high temperatures for a period of time sufficient to render the biomass amenable to digestion. The pretreated biomass is digested to produce useful products such as feedstocks, fuels, and compounds including fatty acids, sugars, ketones and alcohols. Alternatively, the pretreatment process includes the addition of an oxidizing agent, selected from the group consisting of oxygen and oxygen-containing gasses, to the mixture under pressure. The invention is also directed to a method for the recovery of calcium from the pretreated biomass.
    Type: Grant
    Filed: July 27, 1993
    Date of Patent: February 2, 1999
    Assignee: The Texas A&M University System
    Inventors: Mark T. Holtzapple, Richard R. Davison
  • Patent number: 5693296
    Abstract: Lignocellulose-containing materials are treated with lime (calcium hydroxide) and water at a relatively high temperature and for a certain period of time under certain conditions. The process variables were: lime loading which ranged from about 2 to about g Ca(OH).sub.2 /100 g dry material; water loading which ranged from about 6 to about 19 g water/g dry material; treatment temperature which varied from about 50.degree. C. to about 150.degree. C.; and treatment time which varied from about 1 to about 36 hours. The effects of treatment time and temperature were interdependent.A process for lime recovery is developed. The soluble Ca(OH).sub.2 was washed out of the pretreated material with water and converted to insoluble CaCO.sub.3, by reacting with CO.sub.2, and was thus separated. The CaCO.sub.3 can be heated to produce CaO and CO.sub.2. The CaO is hydrated to Ca(OH).sub.2 which can be reused as the lignocellulose treatment agent. Carbon dioxide is reused for lime recovery.
    Type: Grant
    Filed: September 6, 1994
    Date of Patent: December 2, 1997
    Assignee: The Texas A&M University System
    Inventors: Mark T. Holtzapple, Richard R. Davison, Murlidhar Nagwani
  • Patent number: 5171592
    Abstract: An improved biomass refining process is disclosed which is considerably more efficient and cost effective than conventional refining processes. The apparatus and method of the present invention employs superheated steam to dry the solid components and uses the excess steam generated in the drying step to concentrate the liquid components, solidify soluble components and expel noncondensible components. The present invention further employs improved Ammonia Freeze Explosion technology to further enhance the food value of biomass and the solid fiber components separated from the biomass during refining.
    Type: Grant
    Filed: December 19, 1991
    Date of Patent: December 15, 1992
    Assignee: Afex Corporation
    Inventors: Mark Holtzapple, Richard R. Davison, Earnest D. Stuart
  • Patent number: 4733636
    Abstract: A vaporizer for vaporizing liquid fuels having improved heat transfer and controls for vaporization of liquid fuels in response to varying degrees of fuel vapor demand and temperature requirements having a heat exchanger formed from multiple chambers having opposing surfaces composed of inert material at least at said surfaces with small but effective passages formed therebetween and the opposing surfaces being in small but effective passage relationship for sufficient length for the surface tension between a liquid fuel and the opposing surfaces of said multiple chambers to spread the liquid fuel over the opposing surfaces of the multiple chambers for maintaining said liquid fuel in relatively constant and thin liquid relationship to the opposing surfaces of the multiple chambers of the heat exchanger until the liquid fuel is vaporized; a delivery system for delivering liquid fuel to the heat exchanger; a heat delivery system for delivering heat and a heat exchanger for vaporizing the liquid fuel therein and
    Type: Grant
    Filed: November 7, 1986
    Date of Patent: March 29, 1988
    Inventors: William B. Harris, Richard R. Davison
  • Patent number: 4228790
    Abstract: A Solar Heater for collecting solar radiation in a fluid having a base, a flexible fluid retaining member connected adjacent the base for retaining a fluid, and for collecting the radiation of the sun, expansion limiting members connected to the base and positioned with respect to the flexible fluid retaining members for limiting the expansion of the flexible fluid collecting member, as a fluid is flowed through said flexible fluid retaining members by introducing the fluid through a flow way for flowing the fluid therein and a flow way for flowing the fluid therefrom.
    Type: Grant
    Filed: January 10, 1977
    Date of Patent: October 21, 1980
    Inventors: Richard R. Davison, William B. Harris, Salomon Maldonado
  • Patent number: 4216751
    Abstract: A fuel system adapted for use as the primary fuel source with a conventionally fueled and spark ignited internal combustion engine having a fuel tank for the primary fuel, a fuel pump for the primary fuel for pumping the primary fuel out of the fuel tank; a primary fuel vaporizer connected in communication with the pump and in heat conductive communication with a heat source for vaporizing the primary fuel, a vapor regulator means in vapor communication with the fuel vaporizer and the internal combustion engine for supplying fuel in varying amounts in response to varying conditions of demand on the engine and means connected to the system for sensing the conditions in the system and for switching said conventional fuel supply off and said primary fuel on when the conditions are sufficient for said primary fuel to operate the engine.
    Type: Grant
    Filed: April 26, 1976
    Date of Patent: August 12, 1980
    Inventors: Richard R. Davison, William B. Harris
  • Patent number: 3931851
    Abstract: A liquid aquifer energy storage method by which hot water is collected and stored in underground aquifers during the summer months and made available for heating during winter months. The liquid aquifer energy storage method also allows for the storage of cold water during the winter months for use in cooling during the summer months. The liquid aquifer energy storage method includes heating water and hot and warm zones within the aquifer or aquifers for storage of hot and warm water, respectively. Additionally, the method includes cooling water and cold and cool zones in the aquifer or aquifers for storage of cold and cool water.
    Type: Grant
    Filed: February 1, 1974
    Date of Patent: January 13, 1976
    Assignee: William D. Morse, Jr.
    Inventors: William B. Harris, Richard R. Davison