Patent ID: 9468869
Filing Date: 2016-10-18
CPC Classification: B01D,C02F,Y10T

Claim Text:
1. A method for washing a filter for filtering water or wastewater, said method including the steps of: (a) providing a filter having a filter bed in which at least some impurities are removed from influent; (b) positioning an air grid in said filter bed, said air grid including a drop pipe, at least one header and at least one lateral; (c) providing an adapter for permitting vertical adjustment of said drop pipe, said adapter forming an air chamber along a portion of said drop pipe between a first end of said drop pipe and a second end of said drop pipe, said drop pipe having at least one orifice in communication with said air chamber such that air from said air chamber passes into said drop pipe and travels downwardly through said drop pipe during washing of said filter bed; and, (d) directing air through said air grid into said filter bed to remove impurities trapped in said filter bed during a filtration cycle.