METHOD OF REMOVING METAL SALTS FROM WASH WATERS Russian patent published in 1999 - IPC

FIELD: waste water treatment. SUBSTANCE: invention relates to treating water when rinsing parts in electroplating process, printed-circuit card manufacture, and nonferrous metal etching process. Rinse water consecutively passes through cationite and anionite and, desalted, returns into rinse bath. Saturated cationite is regenerated with acid solution. Resulting eluate is divided into two portions in 1:3 to 1:1.5 proportion. The first portion is used to adjust working solution and the second one for repeated regeneration of cationite. Anionite is regenerated with alkali solution to form eluate which is decomposed on diaphragm electrolyzer into acid and alkali that are used to regenerate cationite and anionite, respectively. EFFECT: reduced consumption of reagent and improved environmental condition due to utilization of regeneration solutions in closed circuit. 1 dwg