Patent ID: 6733674
Filing Date: 2004-05-11
Classification: C02F

Abstract:
A method of dewatering sludge comprising sequentiallyi) adding an effective amount of a cellulolytic enzyme preparation having only endoglucanase activity to the sludge; ii) adding an effective amount of one or enzymatic or chemical oxidants to the sludge; iii) adding an effective amount of one or more flocculants to the sludge to form a mixture of water and coagulated and flocculated solids; and iv) separating the coagulated and flocculated solids from the water, wherein the enzymatic oxidants are selected from the group consisting of peroxidase, laccase and tyrosinase, the chemical oxidants are selected from the group consisting of potassium permanganate, hydrogen peroxide, sodium peroxide, ammonium persulfate and manganese dioxide and the flocculants are selected from the group consisting of copolymers and terpolymers of (meth)acrylamide with dimethylaminoethyl methacrylate (DMAEM), dimethylaminoethyl acrylate (DMAEA), diethylaminoethyl acrylate (DEAEA), diethylaminoethyl methacrylate (DEAEM) or their quaternary ammonium forms made with dimethyl sulfate, methyl chloride of benzyl chloride and having a molecular weight in excess of one million.