Method and apparatus for removing impurities from liquids

Abstract

In a method and apparatus for removing impurities from a liquid, the liquid containing impurities is supplied to an electrolytic bath at a pressure higher than atmospheric pressure. Electrolysis is performed by applying a voltage to electrodes consisting of a metal which easily dissolves upon electrolysis. The liquid is then exposed to atmospheric pressure, and is treated in a flotation separation tank. Fine bubbles formed during the treatment of the liquid in the flotation separation tank attach to the impurities flocculated in the liquid by electrolysis. The flotation separation of the flocculated impurities is performed very efficiently, and high-purity water can be recovered. The apparatus comprises an electrolytic bath consisting of a pressure vessel, in which electrodes of a metal which easily dissolves upon electrolysis are housed, and a constant current source for applying a voltage to said electrodes so as to obtain a predetermined current density in a liquid contained in said electrolytic bath, wherein impurities in the liquid are caused to flocculate by a hydroxide of the metal.

Dependencies are inferred from the claim text.