Patents by Inventor Stephen Grocott

Stephen Grocott 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).

  • Patent number: 6616902
    Abstract: A process is disclosed for the treatment of an alumina process feedstock prior to transferring the treated feedstock to an alumina process for extracting refined alumina from the treated feedstock. The treatment process includes the following steps: (a) heating the alumina process feedstock to a temperature of 400C. to 650C. by direct contact with combustion gases, and (b) cooling the heated feedstock to a temperature at which it can be handled and fed to the alumina process. The treatment process is characterised by controlling the contact time of the solid alumina process feedstock at temperatures in the above range in step (a) to less than 5 minutes.
    Type: Grant
    Filed: April 25, 2001
    Date of Patent: September 9, 2003
    Assignee: Comalco Aluminium Limited
    Inventors: Michael Hollitt, Stephen Grocott, Gerard Roe
  • Patent number: 6582670
    Abstract: A process is provided for the treatment of an alumina process feedstock prior to transferring the treated feedstock to an alumina process for extracting refined alumina from the treated feedstock. The treatment process includes: (a) heating the alumina process feedstock to a temperature of 400° C. to 650° C. by direct contact with combustion gas, and (b) cooling the heated feedstock to a temperature at which it can be handled and fed to the alumina process. The treatment process also includes controlling the contact time of the alumina process feedstock at temperatures in step (a) to ensure decomposition of alumina trihydrate and alumina monohydrate. The process also includes: (i) limiting the maximum temperature of incoming gas to a stage of the process in which the alumina process feedstock reaches the above temperature range of 400° C. to 650° C.
    Type: Grant
    Filed: June 18, 2001
    Date of Patent: June 24, 2003
    Assignee: Comalco Aluminum Limited
    Inventors: Michael Hollitt, Stephen Grocott, John Peter Kisler, Colin John Beeby