초록 ▼

A chemical method is provided for the dewatering of biological sludge that has been digested by a thermophilic digestion process. Five versions of the chemical sludge dewatering method are presented. The primary component in the five versions is a polyquaternary amine, preferably of the di-allyl di-

A chemical method is provided for the dewatering of biological sludge that has been digested by a thermophilic digestion process. Five versions of the chemical sludge dewatering method are presented. The primary component in the five versions is a polyquaternary amine, preferably of the di-allyl di-methyl ammonium chloride (DADMAC) variety and from the epichlorohydrin di-methyl amine (epi-DMA) variety. By the first sludge dewatering method, the polyquaternary amine is added directly, along with a polyacrylamide, to the biological sludge. By the second sludge dewatering method, the polyquaternary amine and an anionic polyacrylamide are added separately. By the third sludge dewatering method, a quaternized polyacrylamide, having the polyquaternary amine as part of its polymer chain, is produced by copolymerization of acrylamide with monomers of polyquaternary amine quaternization and is added individually to the sludge. By the fourth sludge dewatering method, the quaternized polyacrylamide from method three is added in concert with a cationic polyacrylamide to the sludge. By the fifth sludge dewatering method, aluminum sulfate, ferric chloride and blends thereof are added, along with polyquaternary amine, as the primary component to the sludge.

대표청구항 ▼

[ What is claimed as invention is:] [1.] A method for dewatering biological sludge that has been digested by a thermophilic digestion process comprising:a. adding polymeric quaternary ammonium compounds, aluminum sulfate, ferric chloride and blends thereof, as primary component, to the biological sl

[ What is claimed as invention is:] [1.] A method for dewatering biological sludge that has been digested by a thermophilic digestion process comprising:a. adding polymeric quaternary ammonium compounds, aluminum sulfate, ferric chloride and blends thereof, as primary component, to the biological sludge; andb. adding polyacrylamide to the biological sludge; such that any combinations of the primary component and of the polyacrylamides enhance dewatering of the sludge.