Patent ID: 6387283
Filing Date: 2002-05-14
Classification: B01D

Abstract:
A liquid filtering apparatus comprising:a vessel which contains a bed of particulate or granular filter medium, said bed having an upper side, an upper part, a lower part below said upper part, a filter-medium washer located above said upper side of said bed, a circulator for continuously transferring dirty filter medium from said lower part of said bed to said filter-medium washer, and for transferring washed filter medium from said filter-medium washer to said upper part of said bed, said washer including a wash chamber defined between walls that have at least a vertical extension, said circulator causing said dirty filter medium to be moved downwardly through said wash chamber and causing a filtered washing liquid to be moved up from said upper side of said bed through said wash chamber, and an adjuster for adjusting the length of said walls of said wash chamber in the direction of filter-medium flow from said upper part to said lower part of the bed.