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:
Mar. 20, 1990
Filed:
May. 08, 1989
Robert R Grinstead, Walnut Creek, CA (US);
The Dow Chemical Company, Midland, MI (US);
Abstract
The invention relates to a cyclic process for the removal of NO.sub.x and SO.sub.x from a gas stream containing NO.sub.x and SO.sub.x. The gas stream is scrubbed with an aqueous reaction solution containing an organic, water-soluble, polymeric chelate containing a polyvalent metal ion. The NO.sub.x is absorbed and in the presence of SO.sub.x, the imidodisulfonate is formed. The aqueous reaction solution containing chelate and imidodisulfonate is contacted with a first membrane separation means, wherein calcium oxide is added to the first permeate stream, resulting in the precipitation of calcium sulfite. The calcium sulfite is filtered from the first permeate stream, the first permeate stream combined with the first non-permeate stream, and the combined stream contacted with a second membrane separation means which removes a portion of the water and other low molecular weight materials, with recycle of the remaining non-permeate stream containing chelate to the scrubber. Water-soluble alkali is added to the process as needed.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile