Apparatus and method for filtering a fluid

Claim 1

Apparatus for use in filtering a fluid so as to remove contaminants therefrom comprising: a first filter unit including first and second filter vessels and having an inlet and an outlet; a source of contaminated fluid; means connecting said inlet of said first filter unit to said source of contaminated fluid and forming a passageway for flow of contaminated fluid therethrough; a discharge conduit; means connecting said outlet of said first filter unit to one end of a discharge conduit and forming a passageway for flow of filtered fluid therethrough; a second filter unit including third and fourth filter vessels and having an inlet and an outlet; means connecting said inlet of said second filter unit to said source of contaminated fluid and forming a passage for flow of contaminated fluid therethrough; means connecting said outlet of said second filter unit to said discharge conduit and forming a passageway for flow of filtered fluid therethrough; means connecting said discharge conduit to said source of contaminated fluid and forming a passageway for flow of fluid therethrough so that when the contamination is less than a predetermined level said first and second filter units may be by-passed; means for opening or closing each of said passageways; a plurality of filter elements, each of said filter elements having an upper portion, an opening and filtering material and, for each of said filter elements, each of said openings extending to be continuous with said filtering material at said upper portion of said filter element; a plurality of O-rings, each of said O-rings engaging one of said filter elements; means in each of said four filter vessels for mounting said filter elements, said means for mounting comprising: a first plate fixedly secured to an inner surface of said vessel in sealing relationship therewith; means for fixedly securing said first plate to said inner surface; a plurality of openings in said first plate for receiving fluid, each of said openings being aligned with one of said filter openings; a plurality of filter baskets, each having an upper portion supported on said first plate and passing through one of said first plate openings; a first sealing gasket supported by said first plate and having a pluraltiy of openings aligned with said openings in said first plate and located between portions of said filter baskets and said first plate, portions of said first sealing gasket also being located between said plurality of filter baskets; a second plate spaced from said first plate, but located next to each of said upper portions of said plurality of filter baskets, and mounted in said vessel for relative longitudinal movement in said vessel and having a plurality of openings aligned with said openings in said first plate; a second sealing gasket spaced from said first sealing gasket and having a plurality of openings aligned with said openings in said first sealing gasket and located between portions of said filter baskets and said second plate, each of said openings in said second sealing gasket being less in size than said filter element openings; and means for applying a force tending to move said second plate toward said first plate to effect a seal between said filter baskets and said first plate and between said filter baskets and said second plate.