Patents by Inventor David Winborne

David Winborne 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).

  • Reducing cyanide consumption in gold recovery from finely ground sulphide ores and concentrates
    Patent number: 7488370
    Abstract: Precious metals such as gold can be extracted from a refractory ore using a conventional cyanide leaching step and with reduced cyanide consumption by pre-treating the ore prior to cyanide leaching. The refractory ore is pretreated by fine grinding and an initial leaching step which uses inexpensive limestone and lime to maintain the initial leach relatively alkaline. Oxygen is added to the initial leaching step and the conditions are carefully controlled to only partially oxidize the ground ore to between 9-15%. The initial leaching step can be carried out at temperatures of less than 100 degrees C. and at atmospheric pressures. The pre-treated ore is then leached by a conventional cyanide leaching step to recover the precious metal and cyanide consumption can be reduced by more than two thirds.
    Type: Grant
    Filed: October 22, 2003
    Date of Patent: February 10, 2009
    Assignee: Xstrata Queensland Ltd.
    Inventors: Michael M Hourn, Rodrigo U Ventura, John A Willis, David Winborne
  • Reducing cyanide consumption in gold recovery from finely ground sulphide ores and concentrates
    Publication number: 20060185475
    Abstract: Precious metals such as gold can be extracted from a refractory ore using a conventional cyanide leaching step and with reduced cyanide consumption by pre-treating the ore prior to cyanide leaching. The refractory ore is pretreated by fine grinding and an initial leaching step which uses inexpensive limestone and lime to maintain the initial leach relatively alkaline. Oxygen is added to the initial leaching step and the conditions are carefully controlled to only partially oxidize the ground ore to between 9-15%. The initial leaching step can be carried out at temperatures of less than 100 degrees C. and at atmospheric pressures. The pre-treated ore is then leached by a conventional cyanide leaching step to recover the precious metal and cyanide consumption can be reduced by more than two thirds.
    Type: Application
    Filed: October 22, 2003
    Publication date: August 24, 2006
    Inventors: Michael Hourn, Rodrigo Ventura, John Willis, David Winborne
  • Method for treating precious metal bearing minerals
    Patent number: 6833021
    Abstract: A method of processing a mineral composition comprising a refractory material the method comprising milling the composition to a particle size of P80 of less than 25 microns and leaching said composition with a solution comprising lime and/or limestone in the presence of an oxygen containing gas.
    Type: Grant
    Filed: May 14, 2001
    Date of Patent: December 21, 2004
    Inventors: Michael Matthew Hourn, Rodrigo Ulep Ventura, John Anthony Willis, David Winborne