ELECTRODIALYZER AND METHOD FOR REGENERATING A WASTE SOLUTION FROM PHOTOGRAPHIC PROCESSING

摘要

A method of regenerating a waste photographic processing solution (e.g., a waste developing solution or a waste bleaching-fixing solution) by electrodialysis utilizing ion exchange membranes, which uses an electrodialyzer characterized by the arrangement of ion exchange membranes employed therein that a space between a cathode and an anode is partitioned by cation exchange membranes and anion exchange membranes alternately arranged, and an anode compartment is provided in a first place in the direction from the anode to the cathode, and wherein there is further provided a plural number of desalting compartments through each of which the waste photographic processing solution is passed, each of which compartments is partitioned by a cation exchange membrane on the cathode side and by an anion exchange membrane on the anode side, and an equal number of concentrating compartments, through each of which a specific solution for the concentrating compartment is passed, and each of which compartments is partitioned by an anion exchange membrane on the cathode side and by a cation exchange membrane on the anode side) arranged alternately in such a way that a desalting compartment is positioned on the side farthest from the anode, wherein a concentrating compartment that it is partitioned by cation exchange membranes on both sides thereof is provided adjacent to the cathode side of the desalting compartment partitioned on the side farthest from the anode, and a cathode compartment is provided adjacent to the last concentrating compartment, and wherein a common solution of electrolytes is supplied to both the cathode and the anode compartments of the electrolyzer and circulated therethrough.