Patent ID: 6123853
Filing Date: 2000-09-26
Classification: C02F,C22B,Y02P

Abstract:
A method for reducing the amount of free nickel and nickel oxides free iron and ferrous oxides in waste water containing alkali metal salts, which comprises:feeding waste water containing metals and caustic into a cell liquor feed line mixing the fluids and flowing the mixed fluids to a first magnet;magnetically removing about one third of said metal present in the mixed fluids and forming a first fluid;evaporating a significant amount of water out of said first fluid using at least one evaporator and raising the temperature of the first fluid above 330.degree. F. and forming a highly concentrated solution, and then further evaporating using flash pans and forming a second fluid:cooling said second fluid using at least one cooler and forming a first cooled solution;continuously providing the first cooled solution to a second magnet;magnetically removing an additional amount of metal from said first cooled solution and forming a second cooled solution;filtering said second cooled solution using at least one filter and forming a filtered solution;continuously providing the filtered solution to a third magnet and;magnetically removing any remaining portion of said filtered solution and forming an alkali metal hydroxide.