Patents by Inventor Christopher Fleming

Christopher Fleming 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: 20080105088
    Abstract: Processes are provided for recovering precious metals from refractory materials using thiosulfate lixiviants. The processes can employ lixiviants that include at most only small amounts of copper and/or ammonia and operate at a relatively low pH, reduction of polythionates, inert atmospheres to control polythionate production, and electrolytic solutions which provide relatively high rates of precious metal recovery.
    Type: Application
    Filed: October 29, 2007
    Publication date: May 8, 2008
    Applicant: PLACER DOME TECHNICAL SERVICES LIMITED
    Inventors: Jinxing Ji, Christopher Fleming, Paul West-Sells, Ralph Hackl
  • Publication number: 20070231436
    Abstract: The invention relates to a method of baking frozen dough pieces using a multi-step baking program that yields a baked product that is essentially indistinguishable from a baked product prepared from freshly prepared non-frozen dough. More particularly, the invention is concerned with a method of baking a frozen dough piece in an oven using a multi-step baking program. The method has a first step of heating the frozen dough piece in an oven comprising a humid atmosphere with a dewpoint of at least 40° C. for a sufficiently long period to completely thaw the exterior of the dough piece to a depth of at least 5 mm, preferably of at least 8 mm, and a subsequent step of baking the dough piece in an oven comprising a dry atmosphere with a temperature of at least 140° C., to obtain a baked product exhibiting a soft crumb and a crispy, browned crust.
    Type: Application
    Filed: January 26, 2004
    Publication date: October 4, 2007
    Applicant: CSM NEDERLAND B.V.
    Inventors: Derek Kemp, Christopher Fleming, Brian Skelton, Peter Moret
  • Publication number: 20060133974
    Abstract: The present invention is directed to a precious metal recovery process in which basic ferric sulphates and/or jarosites are controlled by a number of mechanisms, including control of the oxidation reaction conditions in the first autoclave compartment, hot curing of the autoclave discharge slurry, and/or contacting of the autoclave feed slurry with the hot cured discharge liquid.
    Type: Application
    Filed: October 11, 2005
    Publication date: June 22, 2006
    Applicant: Placer Dome Technical Services Limited
    Inventors: Jinxing Ji, James King, Christopher Fleming, Cesare Ferron
  • Publication number: 20050188791
    Abstract: A hydrometallurgical process to leach at least one base metal from one or more base metal sulphide feeds comprising the steps of providing a base metal sulphide feed; processing at least a portion of the feed by roasting to reduce the content of sulphur therein to a predetermined sulphur content level; directing some or all of the processed feed with or without some of the unprocessed feed to an oxidative leach step to carry out an oxidative leach step under conditions sufficient to recover at least a portion of the base metal from the feed, the predetermined sulphur content level being selected so as not to exceed that which is required to provide a source of heat for the oxidative leach step and to provide sufficient sulphate to complex the portion of the base metal being recovered
    Type: Application
    Filed: February 7, 2005
    Publication date: September 1, 2005
    Inventors: Larry Seeley, Cesare Ferron, Christopher Fleming
  • Patent number: 6919030
    Abstract: A process for recovering cyanide from feed material containing cyanide and copper involves the steps of: (a) contacting the feed material with a strong base anion exchange resin whereby copper and cyanide from the feed material are adsorbed onto the resin; (b) contacting the resulting resin with an eluant solution containing free cyanide ion to elute copper and cyanide from the resin; (c) separating the eluted resin from the eluting solution or eluate from step (b); (d) acidifying the eluate from step (b) to precipitate copper; (e) separating the acidified solution from the precipitate in step (d) and alkalizing directly or after concentration the separated solution containing HCN; (f) contacting the eluted resin from step (b) with an acid to condition the resin and remove additional cyanide while leaving most of the copper in the resin phase; (g) converting the HCN solution formed in step (f) to cyanide ion, directly or after concentration of the HCN solution, by the addition of alkali; and (h) returning the
    Type: Grant
    Filed: February 24, 2003
    Date of Patent: July 19, 2005
    Assignee: Hannah Technologies Limited Partnership
    Inventors: John A. Thorpe, Christopher A. Fleming
  • Publication number: 20030205533
    Abstract: A process for recovering cyanide from feed material containing cyanide and copper involves the steps of: (a) contacting the feed material with a strong base anion exchange resin whereby copper and cyanide from the feed material are adsorbed onto the resin; (b) contacting the resulting resin with an eluant solution containing free cyanide ion to elute copper and cyanide from the resin; (c) separating the eluted resin from the eluting solution or eluate from step (b); (d) acidifying the eluate from step (b) to precipitate copper; (e) separating the acidified solution from the precipitate in step (d) and alkalizing directly or after concentration the separated solution containing HCN; (f) contacting the eluted resin from step (b) with an acid to condition the resin and remove additional cyanide while leaving most of the copper in the resin phase; (g) converting the HCN solution formed in step (f) to cyanide ion, directly or after concentration of the HCN solution, by the addition of alkali; and (h) returning the
    Type: Application
    Filed: February 24, 2003
    Publication date: November 6, 2003
    Applicant: Hannah Technologies Limited Partnership
    Inventors: John A. Thorpe, Christopher A. Fleming
  • Publication number: 20020152845
    Abstract: A method for recovering a precious metal from a host material, comprises the steps of subjecting the host material to an oxidative pressure leach process, in the presence of a halide ion constituent, preferably a chloride ion, which is reactive with the precious metal, and at an elevated temperature of at least 170° C. to cause at least a portion of the precious metal to be extracted by a leach solution in the form of a precious metal-bearing chloride complex, and recovering the precious metal from the leach solution.
    Type: Application
    Filed: October 26, 2001
    Publication date: October 24, 2002
    Inventors: Christopher A. Fleming, David Dreisinger, P. Terry O'Kane
  • Patent number: 6451275
    Abstract: Briefly stated, there is provided a method for reducing cyanide consumption in precious metals mining extraction processes involving a sulfur bearing ore body, comprising the steps of providing a precious metal bearing material having intermediate sulfur oxidation products, and exposing the material to sulfur dioxide gas, bisulfite ions or sulfite ions, in a manner to cause at least a portion of the intermediate sulfur oxidation products to be rendered unreactive with cyanide.
    Type: Grant
    Filed: July 10, 2000
    Date of Patent: September 17, 2002
    Assignee: Lakefield Research Limited
    Inventor: Christopher A. Fleming
  • Patent number: 6344068
    Abstract: A process for recovering gold from thiosulfate leach solutions and slurries in which gold is loaded into an ion exchange resin. Gold is recovered from the resin by elution with polythionate ions and the resin is regenerated with sulfide or sulfite. Gold is recovered from the eluate by precipitation with sulfide ions, cementation or electrowinning. The invention also provides for a process of manufacturing polythionate ion solutions suitable for eluting gold from ion exchange resins.
    Type: Grant
    Filed: April 4, 2000
    Date of Patent: February 5, 2002
    Assignee: Barrick Gold Corporation
    Inventors: Christopher Fleming, John Wells, Kenneth G. Thomas
  • Patent number: 6315812
    Abstract: A method for recovering a precious metal from a host material, comprises the steps of subjecting the host material to an oxidative pressure leach process, in the presence of a halide ion constituent which is reactive with the precious metal, and at a temperature sufficient to cause at least a portion of the precious metal to be extracted by a leach solution; and recovering the precious metal from the leach solution.
    Type: Grant
    Filed: April 28, 1999
    Date of Patent: November 13, 2001
    Assignee: International PGM Technologies Ltd
    Inventors: Christopher A. Fleming, David Dreisinger, P. Terry O'Kane
  • Patent number: 5785736
    Abstract: A process for treatment of precious metal ores in which gold is leached from an oxidized ore slurry using a thiosulfate salt lixiviant and copper catalyst. Gold and copper are subsequently loaded onto an ion exchange resin. Copper is recovered from the resin by elution with a thiosulfate solution; gold is recovered from the resin by elution with a thiocyanate colution. Gold is recovered from the eluate by precipitation, electrowinning, or cementation.
    Type: Grant
    Filed: July 16, 1996
    Date of Patent: July 28, 1998
    Assignee: Barrick Gold Corporation
    Inventors: Kenneth G. Thomas, Christopher Fleming, Andrew R. Marchbank, David Dreisinger
  • Patent number: 5536297
    Abstract: A process for recovering gold in which an ore slurry of refractory sulfidic and refractory carbonaceous ore having preg-robbing characteristics due to the presence of organic carbon is subjected to pressure oxidation in an autoclave. The oxidized ore slurry is mixed with a thiosulfate salt lixiviant, which mixture is maintained at a pH between 7 and 8.7 while the slurry is agitated in a stirred tank reactor system having agitated leach tanks. Gold is recovered from the gold-bearing leachate by cementation, adsorption on an adsorbent, or cyanidation.
    Type: Grant
    Filed: February 10, 1995
    Date of Patent: July 16, 1996
    Assignee: Barrick Gold Corporation
    Inventors: Andrew R. Marchbank, Kenneth G. Thomas, David Dreisinger, Christopher Fleming
  • Patent number: 5478538
    Abstract: The specification discloses a process for removing radionuclides from zircon. The process involves thermally decomposing the zircon in the presence of suitable additives, extracting the radionuclides chemically and recovering zirconia and silica. Suitable additives include fluxes, silica and any oxide capable of forming a silicate with silica when heated. Chemical treatments disclosed include leaching with mineral acids and strong organic acids. Methods of stabilizing the radionuclides extracted by leaching are also disclosed. One method involves spray roasting. Another method involves neutralization of leach liquor and recovery of radionuclide solids by filtration or other suitable liquid/solid separation techniques.
    Type: Grant
    Filed: December 14, 1993
    Date of Patent: December 26, 1995
    Assignee: Wimmera Industrial Minerals Pty Ltd
    Inventors: Michael J. Hollitt, Ross A. McClelland, Matthew J. Liddy, Ian E. Grey, Christopher A. Fleming
  • Patent number: 5411575
    Abstract: A hydrometallurgical process for treating copper ores or concentrates containing gold by simultaneously leaching both copper and gold into an aqueous cyanide solution, recovering copper and gold in metallic form by electrowinning or cementation and regenerating cyanide ions is provided.
    Type: Grant
    Filed: March 25, 1994
    Date of Patent: May 2, 1995
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Christopher A. Fleming, Walther G. Grot, John A. Thorpe
  • Patent number: 5320720
    Abstract: Increased efficiency of extraction of silver and gold from ore materials thereof containing active carbonaceous material is obtained by conducting the extraction in two stages. In a first stage a portion of the silver and of the gold when present is extracted in a cyanide leach solution. The leached solids residue is contacted with activated carbon so that the silver and the gold when present are adsorbed on the activated carbon at elevated temperature (most preferably at about 35.degree. C. to about 100.degree. C.). In a modification, a slurry of the ore material is treated with cyanide and the precious metal adsorbed directly from the cyanided slurry with activated carbon at elevated temperature up to about 70.degree. C.
    Type: Grant
    Filed: January 5, 1993
    Date of Patent: June 14, 1994
    Assignee: Prime Resources Group Inc.
    Inventors: Alfred S. Hayden, Christopher A. Fleming, Chandulal P. Patel
  • Patent number: 4608176
    Abstract: A method of regenerating strong-base anion exchange resins which have been used in the extraction of complex anions followed by elution with a thiocyanate strip solution is provided. The method involves the use of ferric ions in a regenerating solution together with a substitute anion for attachment of the resin, the regeneration taking place under conditions in which ferric-thiocyanate complex cations are formed and washed from the resin by the regenerating solution. The thiocyanate can be recovered by neutralizing the regenerating solution to precipitate ferric hydroxide and leave thiocyanate in solution.
    Type: Grant
    Filed: December 18, 1984
    Date of Patent: August 26, 1986
    Assignee: Council for Mineral Technology
    Inventor: Christopher A. Fleming