Apparatus for removing impurities from water or wastewater and a method of installing a fluid distribution system therein

A method of installing an air scour system in a filter having a filter compartment with at least one vertically extending sidewall, a bottom and a filter bed including at least one layer of filter media, said method comprising the steps of:

• (a) providing an air grid for air scouring a filter bed, said air grid includes at least one vertically extending drop pipe, at least one horizontally extending header and at least one horizontally extending lateral;
• (b) providing an air source;
• and,
• (c) providing a hollow tubular member for permitting vertical adjustment of said drop pipe during installation of said drop pipe, said hollow tubular member being connected to said air source, said hollow tubular member surrounding a portion of said drop pipe, said hollow tubular member having an internal diameter greater than an external diameter of said drop pipe so that said drop pipe can slide in the internal diameter of said hollow tubular member during installation of said drop pipe to permit vertical adjustment of said drop pipe during installation of said drop pipe, said portion of said drop pipe having a first orifice that allows said drop pipe to receive pressurized air supplied by said air source.

An apparatus including an air scour system in a filter having a filter compartment with at least one vertically extending sidewall, a bottom and a filter bed including at least one layer of filter media, said apparatus comprising:

• (a) a filter having a filter bed for removing at least some impurities from influent;
• (b) an air grid disposed in said filter bed for directing air through at least a portion of said filter bed, said air grid including a drop pipe having at least one orifice, at least one header and at least one lateral;
• (c) an air source;
• and,
• (d) a hollow tubular member for permitting vertical adjustment of said drop pipe during installation by allowing vertical movement of said drop pipe so that a portion of said drop pipe is allowed to slide through said hollow tubular member at some point during installation of said drop pipe, said hollow tubular member being connected to said air source, said hollow tubular member forming a cavity around said drop pipe and said at least one orifice being in communication with said cavity so that pressurized air supplied to said cavity from said air source is allowed to pass into said drop pipe.