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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.:

US 9790111 B1

PDFFull Text
Date of Patent:
Oct. 17, 2017

Filed:

Nov. 28, 2013

Method for thickening or dehydrating sludge

Applicant:

Roquette Freres, Lestrem, FR;

Inventors:

Laura Crowther-Alwyn, Armentieres, FR;

Medhi Carre, Pelves, FR;

Michel Simon, St Gratien, FR;

Assignee:

Roquette Freres, Lestrem, FR;

Attorney:

Blank Rome LLP

Primary Examiner:

Nam Nguyen

Assistant Examiner:

Julia Wun

Int. Cl.
CPC ...
B01D 21/01 (2006.01); C02F 1/52 (2006.01); B03D 3/00 (2006.01); C08L 33/26 (2006.01); C08L 3/04 (2006.01); D21H 17/29 (2006.01); D21H 17/37 (2006.01); C02F 11/12 (2006.01); C02F 1/54 (2006.01); C02F 1/56 (2006.01); C02F 11/14 (2006.01); C02F 103/32 (2006.01); C02F 103/28 (2006.01);
U.S. Cl.
CPC ...
C02F 1/5263 (2013.01); C02F 1/52 (2013.01); C02F 1/54 (2013.01); C02F 1/56 (2013.01); C02F 11/12 (2013.01); C02F 11/14 (2013.01); C08L 3/04 (2013.01); C08L 33/26 (2013.01); D21H 17/29 (2013.01); D21H 17/37 (2013.01); C02F 2103/28 (2013.01); C02F 2103/32 (2013.01);
Abstract

Disclosed is a method for thickening or dehydrating sludge, which includes at least: a) a step of adding flocculants to the sludge to be treated; b) a step of flocculation by agitation of the sludge with the flocculants thus added in order to form a mixture of flocks and an aqueous solution; c) a step of mechanical separation of the flocks and the aqueous solution formed during the preceding step; d) a step of recovering the aqueous solution and the flocks that make up a treated sludge; wherein: the added flocculants are made up of at least one cationic starch (S) and at least one cationic polyacrylamide (P); the cationic starch or starches (S) including a fixed weight percentage of nitrogen of at least 2%; and the weight ratio (R) w/(w+w), expressed as solids, is included between 0.6 and 0.99.

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