Patent ID: 6544425
Filing Date: 2003-04-08
Classification: B01D,C02F,F26B

Abstract:
A method of dewatering a mixture of coal railings, water and contaminants from a coal refuse slurry pond, the method comprising the steps of:(a) providing a tank having a base surface and introducing said mixture of coal, tailings, water, and contaminants to said tank and allowing said coal tailings to settle on said base surface, where the tank has an entry point where the mixture of tailings, water and contaminants are introduced into the tank and a discharge point where the coal tailings, water, and contaminants are removed from the tank, and where said entry and discharge points are both elevated from the base surface; (b) removing the coal tailings from said base surface of said rank along with water and contaminants with a conveyer system, and then separating said water and at least some of said contaminants from said coal tailings wherein said separated contaminants are suspended in said separated water; (c) adding an agent selected form one or more of the group consisting of a coagulant and a flocculent to said water and suspended contaminants separated from the coal tailings in step (b); (d) allowing the agent added in step (c) to coagulate or flocculate with the suspended contaminants to form a coagulated or flocculated mass and a quantity of supernatant water; and (e) separating the coagulated or flocculated mass formed in step (d) from the quantity of supernatant water formed in step (d).