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:
Feb. 25, 1992
Filed:
Jun. 10, 1991
Applicant:
Inventors:
Lawrence J Connelly, Oak Lawn, IL (US);
Steven J Abbatello, San Antionio, TX (US);
David C Davis, Chesterfield, MO (US);
David A Undlin, Victoria, TX (US);
Assignee:
Nalco Chemical Company, Naperville, IL (US);
Attorneys:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C01F / ;
U.S. Cl.
CPC ...
423122 ; 423121 ; 423111 ; 423130 ; 210725 ; 210727 ; 210728 ; 210734 ;
Abstract
In the Bayer process for producing alumina from bauxite of the type wherein the bauxite is added to a caustic solution to produce a soluble aluminate solution and an insoluble red mud fraction which is then subjected to one or more separation steps to produce a thickener overflow which is then subjected to a Kelly Filter Press to polish the thickener overflow the improvement which comprises treating the thickener overflow and the filter aid with a filtration improving amount of dextran.