Filter system with external scrubber

A filter system for removing contaminants from a liquid flowing through the system comprising a filter vessel having an inlet into which a contaminated liquid flows and an outlet through which filtered liquid exits said vessel;

• a filter screen supported adjacent said filter vessel outlet and within said vessel;
• a relatively large quantity of particulate filter media in said vessel and supported against said filter screen for normal filter operation wherein contaminants are captured by said particulate filter media and filtered liquid exits through said filter screen and said outlet;
• a closed loop flow circuit for scrubbing the media having a nozzle in said filter vessel directed toward said filter screen, an intermittently operable scrubber apparatus supported exteriorly of said filter vessel having a fluidized media inlet, a cleaned media outlet, and a scrub water discharge, and further including a pump means in said closed loop having a suction inlet in said filter vessel for receiving flow of liquid from the interior of said vessel;
• said nozzle being aligned with said filter screen in a manner such that the media is fluidized when the pump means provides a flow therethrough;
• a scrubing and cleaning screen in said scrubber apparatus through which liquid and removed contaminants can flow while filter media is substantially precluded from flowing therethrough, a scrub water discharge chamber formed contiguous to said scrub screen and connected to discharge contaminants and liquid from said discharge chamber through said scrub water discharge;
• the flow of fluidized media into said scrubber apparatus is separated into a cleaned fluidized media and a dirty water stream and said dirty water stream is discharged therefrom while the cleaned fluidized media is returned to the filter vessel;
• whereby, liquid containing contaminants scrubbed from said particulate filter media can flow through said pump, through said scrub and cleaning screen, into said discharge chamber, and from said scrubber apparatus by means of said scrub water discharge.

A method by which contaminants are removed from a liquid flowing through a filter vessel having an inlet for providing a contaminated liquid flow into one end thereof and an outlet through which filtered liquid can exit said vessel, according to the following steps;

• supporting a filter screen adjacent said filter vessel outlet and within said filter vessel and supporting a relatively large quantity of particulate filter media in said filter vessel and on said filter screen for normal filter operation;
• and, capturing contaminants in said particulate filter media by flowing contaminated liquid through said inlet while filtered liquid exits through said filter screen and said outlet;
• forming a closed loop flow circuit for fluidizing said media and cleaning said media externally of said filter vessel by flowing contaminated liquid from said one end and along a closed loop flow path that includes a nozzle in said filter vessel and a scrubber vessel externally of said filter vessel;
• mounting said nozzle respective to the media on said filter screen to fluidize the media while concurrently flowing the fluidized media along said closed loop;
• forming a fluidized media inlet, a cleaned media outlet, and a scrub water discharge for said scrubber vessel,
• supporting a scrub and separator screen in said scrubber vessel through which removed contaminants can flow while the filter media is substantially precluded from flowing through the scrub and separator screen;
• forming said scrub water discharge chamber contiguous respective to said scrub water screen and connected to discharge contaminants and liquid from said discharge chamber through said scrub water discharge;
• flowing fluidized media along said closed loop circuit by a pump means having a suction inlet in said vessel for receiving flow of liquid from the interior of said vessel;
• and directing said nozzle in said vessel toward said screen means, aligning said nozzle such that said particulate filter media fluidized in the liquid assumes a flow path which scrubs the particulate filter media and translocates removed contaminants from the particulate filter media into the liquid;
• whereby, liquid containing contaminants scrubbed from said particulate filter media is separated therefrom as the fluidized media flows through said scrubber vessel, with the last said liquid flowing into said discharge chamber, and away from said scrub vessel while the media is returned to the nozzle in the filter vessel.

A filter apparatus by which contaminants are removed from a liquid flowing therethrough, comprising:

• a vessel having an inlet for providing a contaminated liquid flow into one end thereof and an outlet through which filtered liquid can exit said vessel;
• a screen means supported upstream of said outlet and within said vessel;
• a quantity of particulate filter media in said vessel and supported by said screen for normal filter operation wherein contaminants are captured by said particulate filter media and filtered liquid exits through said screen means and said outlet;
• a scrubber apparatus connected exteriorly of said vessel and including pipe means connecting the interior of said scrubber to the interior of said vessel by which said particulate filter media can be fluidized and the fluidized media circulated between said vessel and said scrubber apparatus;
• said scrubber apparatus including:
• a housing having a scrubber inlet and an outlet, a scrub screen means mounted within said housing through which liquid and removed contaminants can flow while the filter media is substantially precluded from flowing therethrough, a pump means for moving contaminated liquid from the interior of said vessel to transfer fluidized media to the scrubber inlet;
• a nozzle in said vessel directed toward said scrub screen means, said nozzle being aligned in a manner such that said particulate filter media fluidized in said liquid assumes a flow path which scrubs the particulate filter media and translocates removed contaminants from the particulate filter media into the liquid;
• and discharge means for removing liquid containing contaminants scrubbed from said particulate filter media from said housing by flowing the liquid containing contaminants through said screen means and said discharge means.