The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 09, 2007
Filed:
Sep. 13, 2005
John Burckle, Cincinnati, OH (US);
Rakesh Govind, Cincinnati, OH (US);
Fred Kawahara, Ft. Wright, KY (US);
Richard Scharp, Cincinnati, OH (US);
Henry Tabak, Cincinnati, OH (US);
John Burckle, Cincinnati, OH (US);
Rakesh Govind, Cincinnati, OH (US);
Fred Kawahara, Ft. Wright, KY (US);
Richard Scharp, Cincinnati, OH (US);
Henry Tabak, Cincinnati, OH (US);
United States of America Enviromental Protection Agency, Washington, DC (US);
Abstract
Acidic metal-bearing wastewaters are treated to produce a finished water of sufficient purity to meet discharge standards while recovering metals removed in forms which are commercially valuable. The metals are selectively precipitated, either in a batch or in a continuous system, for removal of individual metal products in a specific sequence of steps from the wastewater. In each step, the pH is adjusted to the specific pH range and sulfide ion is introduced to precipitate the metals, excepting the removal of ferric iron and aluminum which is achieved using hydroxide precipitation. Bioconversion process using unique equipment converts sulfate in the wastewater to the hydrogen sulfide gas required for the precipitation process. This bioconversion process reduces the sulfate in the wastewater so that the water can be directly discharged or used for agricultural applications.