Patents by Inventor Andrew W. Bolland

Andrew W. Bolland 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).

  • Gold recovery using controlled oxygen distribution pressure oxidation
    Patent number: 5489326
    Abstract: A process for recovering gold from a refractory auriferous ore containing sulfide sulfur. An aqueous slurry of refractory auriferous ore is subjected to pressure oxidation in an autoclave while the distribution of oxygen to the various compartments of the autoclave is controlled in order to achieve increased oxygen utilization.
    Type: Grant
    Filed: October 4, 1994
    Date of Patent: February 6, 1996
    Assignee: Barrick Gold Corporation
    Inventors: Kenneth G. Thomas, Herman J. H. Pieterse, Richard A. Williams, Andrew W. Bolland