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:
Aug. 25, 1998
Filed:
Aug. 20, 1996
Carol S Greer, Lisle, IL (US);
Ann M Capozzi, Naperville, IL (US);
Linda S Wilkins, Naperville, IL (US);
Nalco Chemical Company, Naperville, IL (US);
Abstract
The present invention provides a method for removing secondary fiber contaminants from paper mill process waters comprising adding a polyvinyl chloride, a cationic polymeric coagulant and a polymeric flocculant to paper mill process waters containing secondary fiber contaminants in an amount sufficient to agglomerate the secondary fiber contaminants to larger particles sizes, and removing the secondary fiber contaminants from the process water by a dissolved air flotation clarification technique. The addition of particulate polyvinyl chloride in combination with a polymeric coagulant and flocculant prior to the DAF clarification process causes the contaminants to become preferentially coated with the polyvinyl chloride particles. This coating is what causes the subsequent removal of the secondary fiber contaminants in the DAF clarification process to be more effective.