Patents by Inventor Steven E. Sawell

Steven E. Sawell 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).

  • Treatment of fly ASH/APC residues including lead salt recovery
    Patent number: 6319482
    Abstract: The present invention relates to a process for treating fly ash/APC residues chlorides, sulphates, earth alkali metals selected from the group consisting of calcium, potassium, and sodium, and heavy metals selected from the group consisting of lead, which residues are obtained from air pollution control processes that utilize dry/semi-dry line injection, such that said residues may be disposed of as non-hazardous materials. The process comprises the sequential steps of: (a) washing and agitating the fly ash/APC residue (20) with water (50) to form a residue slurry containing solubilized lead salts and calcium chloride; (b) filtering (42) the residue slurry to remove a filtrate (46) having a pH of higher than about 11.8 and containing the solubilized lead salts and calcium chloride; and (c) recovering a first calcium enriched filter cake (44).
    Type: Grant
    Filed: November 18, 1998
    Date of Patent: November 20, 2001
    Assignee: Apex Residue Recovery Inc.
    Inventors: Steven E. Sawell, Stephen A. Hetherington