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:
Sep. 14, 1993
Filed:
May. 21, 1991
Applicant:
Inventor:
Keith E Forrester, Stratham, NH (US);
Assignee:
Wheelabrator Environmental Systems, Inc., Hampton, NH (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C04B / ; A62D / ;
U.S. Cl.
CPC ...
588236 ; 423659 ; 106405 ; 106D / ; 110259 ;
Abstract
Bottom ash arising from solid waste combustion has lead (Pb) sufficient quantity to sometimes fail the EPA TCLP test. Addition of water-soluble phosphate, especially phosphoric acid, increases the immobilization of lead (Pb) so as to make such residues in compliance with the toxicity tests over a substantially broader pH range, particularly with respect to the more stringent TCLP extraction test. The bottom ash may be wet or dry when contracted with the water-soluble phosphate. The contacting is preferably preformed in an enclosed environment to avoid bottom ash contact with or exposure to the ambient atmospheres prior to treatment.