Patents by Inventor Christopher Andrew Fleming

Christopher Andrew 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).

  • Method for thiosulfate leaching of precious metal-containing materials
    Patent number: 8821613
    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: Grant
    Filed: February 4, 2010
    Date of Patent: September 2, 2014
    Assignee: Placer Dome Technical Services Ltd.
    Inventors: Jinxing Ji, Christopher Andrew Fleming, Paul George West-Sells, Ralph Peter Hackl
  • METHOD FOR THIOSULFATE LEACHING OF PRECIOUS METAL-CONTAINING MATERIALS
    Publication number: 20140047954
    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 21, 2013
    Publication date: February 20, 2014
    Applicant: PLACER DOME TECHNICAL SERVICES LTD.
    Inventors: Jinxing Ji, Christopher Andrew Fleming, Paul George West-Sells, Ralph Peter Hackl
  • Method for thiosulfate leaching of precious metal-containing materials
    Patent number: 8597399
    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: Grant
    Filed: February 3, 2011
    Date of Patent: December 3, 2013
    Assignee: Placer Dome Technical Services Limited
    Inventors: Jinxing Ji, Christopher Andrew Fleming, Paul George West-Sells, Ralph Peter Hackl
  • Reduction of lime consumption when treating refractory gold ores or concentrates
    Patent number: 8029751
    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: Grant
    Filed: October 13, 2009
    Date of Patent: October 4, 2011
    Assignee: Placer Dome Technical Services Limited
    Inventors: James A. King, Jinxing Ji, Christopher Andrew Fleming, Cesare Giosue Ferron
  • METHOD FOR THIOSULFATE LEACHING OF PRECIOUS METAL-CONTAINING MATERIALS
    Publication number: 20110132147
    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: February 3, 2011
    Publication date: June 9, 2011
    Applicant: PLACER DOME TECHNICAL SERVICES LTD.
    Inventors: Jinxing Ji, Christopher Andrew Fleming, Paul George West-Sells, Ralph Peter Hackl
  • METHOD FOR THIOSULFATE LEACHING OF PRECIOUS METAL-CONTAINING MATERIALS
    Publication number: 20100132509
    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: February 4, 2010
    Publication date: June 3, 2010
    Applicant: PLACER DOME TECHNICAL SERVICES LTD.
    Inventors: Jinxing Ji, Christopher Andrew Fleming, Paul George West-Sells, Ralph Peter Hackl
  • Method for thiosulfate leaching of precious metal-containing materials
    Patent number: 7704298
    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: Grant
    Filed: April 30, 2004
    Date of Patent: April 27, 2010
    Assignee: Placer Dome Technical Services Limited
    Inventors: Jinxing Ji, Christopher Andrew Fleming, Paul George West-Sells, Ralph Peter Hackl
  • REDUCTION OF LIME CONSUMPTION WHEN TREATING REFRACTORY GOLD ORES OR CONCENTRATES
    Publication number: 20100024603
    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 13, 2009
    Publication date: February 4, 2010
    Applicant: PLACER DOME TECHNICAL SERVICES LTD.
    Inventors: Jinxing Ji, James A. King, Christopher Andrew Fleming, Cesare Giosue Ferron
  • Reduction of lime consumption when treating refractor gold ores or concentrates
    Patent number: 7604783
    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: Grant
    Filed: October 11, 2005
    Date of Patent: October 20, 2009
    Assignee: Placer Dome Technical Services Limited
    Inventors: James A. King, Jinxing Ji, Christopher Andrew Fleming, Cesare Giosue Ferron
  • Method for thiosulfate leaching of precious metal-containing materials
    Patent number: 7559974
    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: Grant
    Filed: October 29, 2007
    Date of Patent: July 14, 2009
    Assignee: Placer Dome Technical Services Ltd.
    Inventors: Jinxing Ji, Christopher Andrew Fleming, Paul George West-Sells, Ralph Peter Hackl
  • Method for thiosulfate leaching of precious metal-containing materials
    Patent number: 7066983
    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: Grant
    Filed: May 27, 2003
    Date of Patent: June 27, 2006
    Assignee: Placer Dome Technical Services Limited
    Inventors: Jinxing Ji, Christopher Andrew Fleming, Paul George West-Sells, Ralph Peter Hackl
  • Method for thiosulfate leaching of precious metal-containing materials
    Publication number: 20040206207
    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: April 30, 2004
    Publication date: October 21, 2004
    Applicant: Placer Dome Technical Services Limited
    Inventors: Jinxing Ji, Christopher Andrew Fleming, Paul George West-Sells, Ralph Peter Hackl
  • Method for thiosulfate leaching of precious metal-containing materials
    Publication number: 20040035252
    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: May 27, 2003
    Publication date: February 26, 2004
    Applicant: Placer Dome Technical Services Limited
    Inventors: Jinxing Ji, Christopher Andrew Fleming, Paul George West-Sells, Ralph Peter Hackl
  • Method for thiosulfate leaching of precious metal-containing materials
    Patent number: 6660059
    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: Grant
    Filed: May 11, 2001
    Date of Patent: December 9, 2003
    Assignee: Placer Dome Technical Services Limited
    Inventors: Jinxing Ji, Christopher Andrew Fleming, Paul George West-Sells, Ralph Peter Hackl
  • Method for thiosulfate leaching of precious metal-containing materials
    Publication number: 20020092377
    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: May 11, 2001
    Publication date: July 18, 2002
    Inventors: Jinxing Ji, Christopher Andrew Fleming, Paul George West-Sells, Ralph Peter Hackl
  • Hydrometallurgical extraction process
    Patent number: 5807421
    Abstract: A hydrometallurgical process for treating copper feed materials containing gold and/or silver by simultaneously leaching copper, gold and/or silver into an aqueous cyanide solution, extracting copper, gold and cyanide with anion exchange resin is provided.
    Type: Grant
    Filed: August 2, 1996
    Date of Patent: September 15, 1998
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Christopher Andrew Fleming, Walther Gustav Grot, John Anton Thorpe
  • Hydrometallurgical extraction and recovery of copper, gold, and silver via cyanidation and electrowinning
    Patent number: 5667557
    Abstract: A hydrometallurgical process for treating copper feed materials containing gold and/or silver by simultaneously leaching copper, gold and/or silver into an aqueous cyanide solution, recovering copper in metallic form by electrowinning and regenerating cyanide ions is provided, wherein high current efficiencies are achieved at high current densities and at low copper concentrations.
    Type: Grant
    Filed: September 26, 1995
    Date of Patent: September 16, 1997
    Assignee: E. I. Du Pont de Nemours and Company
    Inventors: Christopher Andrew Fleming, Walther G. Grot, John Anton Thorpe