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. 28, 1995
Filed:
Jun. 06, 1994
Applicant:
Inventor:
Leo E Nagan, Mercer Island, WA (US);
Assignee:
Diatec Polymers, Batavia, IL (US);
Primary Examiner:
Int. Cl.
CPC ...
C02F / ; D21F / ; D21F / ; D21C / ;
U.S. Cl.
CPC ...
210727 ; 210734 ; 210928 ; 162 29 ; 1621683 ; 1621812 ; 162189 ; 162D / ;
Abstract
A method of treating an aqueous system is disclosed. The method may be used to treat sewage streams as well as aqueous streams in pulp and paper mill processing. The method includes the steps of adding a polymeric composition to an aqueous stream. The composition is an anionically modified acrylamide polymer in an aqueous medium. The polymer is formed by reacting an acrylamide polymer with phosphorous acid, and has at least 5 mole percent phosphonate groups based on the acrylamide content of the polymer, and has a molecular weight of at least about 40,000. the pH of the composition is adjusted to at least about 7.7.