US 5,670,056 A · Chemical-mechanical dewatering process

Abstract

Small, wet particulate material is effectively dried by adding a hydrophobizing agent to coat the surfaces of the particulates, and then mechanically removing water droplets from the surfaces of the particulates. Once on the surface of the particulates, the hydrophobizing reagent makes the particulates relatively more hydrophobic and increases the water contact angle on the particulates. The moisture content of the particulate material can easily be reduced to levels below 20%, below 10%, and even below 5%. The process can be used to dewater a wide variety of constituents including coal particles, clays, sulfides, phosphorous compounds, minerals, metals, waste sludge, etc. Particularly preferred hydrophobizing reagents include mono unsaturated fatty esters and polysiloxane polymers.

Claims25

Dependent claims

A method for dewatering moist particulates, comprising the steps of:

combining a mono-unsaturated fatty ester with a carrier solvent and a moist particulate solution comprised of 1-99% by weight water and 1-99% by weight particulate to form a treated combination, said mono-unsaturated fatty ester comprising less than 10% by weight of said treated combination, said mono-unsaturated fatty ester increasing a contact angle between water and a surface of a particle in said moist particulate solution;
agitating said treated combination to distribute said mono-unsaturated fatty ester on surfaces of said particulates in said treated combination;
and
mechanically removing water from said surfaces of said moist particulates to produce dry particulates.

1 more element

Dependencies are inferred from the claim text.

Chemical-mechanical dewatering process

Life of this patent

Chemical-mechanical dewatering process

Life of this patent

Abstract

Claims25