Scrubbing backwash filter

A method of filtering contaminants from contaminated fluid and exchanging heat comprising:

• a) flowing contaminated fluid into a vessel containing media, the contaminated fluid entering the vessel through an input positioned near a base of the vessel;
• b) passing the contaminated fluid through a cyclone positioned within the vessel for separating heavy and light contaminants in the contaminated fluid;
• c) agitating the contaminated fluid using a mixer positioned above the cyclone;
• d) passing the contaminated fluid radially outward through the media to trap the contaminants therein until a predetermined differential pressure is detected across the media, and by a heat exchanger positioned within the vessel, wherein the heat exchanger receives cold clean fluid from a fluid source and moves the cold clean fluid in a direction generally opposite to the direction of movement of the contaminated fluid to cool the contaminated fluid;
• e) passing the cooled decontaminated fluid through an effluent screen positioned vertically proximate a side of the vessel for discharging the decontaminated fluid from the vessel;
• f) once the predetermined differential pressure across the media is detected, scrubbing the contaminated media and a surface of the heat exchanger by forming a slurry of the contaminated media by activating a mixer extending downwardly from the top of the vessel and comprising first and second propellers rotatable on a drive shaft, the first and second propellers increasing flow of the slurry through the effluent screen;
• wherein a liquid portion of the slurry containing the contaminants is drawn through the effluent screen for discharge from the vessel while the media is retained in the vessel, the effluent screen thereby separating the contaminants from the media and the slurry, and
• g) repeating process (f) until the contaminants are removed from the media and the surface of the heat exchanger.