Filtration system including a back washable pre-filtration apparatus

Abstract

A filtration system for filtering particulate matter from a liquid, the filtration system comprises a pre-filtration apparatus and a main filtration apparatus. The pre-filtration apparatus comprises a vessel having a fluid inlet, a fluid outlet, and a back-washing outlet, and a filtering medium disposed in the vessel and capable of filtering large particulate matter from the liquid and passing fine particulate matter. The fluid inlet and the fluid outlet are positioned such that liquid flowing therebetween is passed through the filtering medium. The fluid outlet and back-washing outlet are positioned such that liquid flowing therebetween is passed through the filtering medium. The main filtration apparatus comprises a vessel having a fluid inlet, a fluid outlet, and a filtering medium disposed in the vessel and capable of filtering fine particulate matter from the liquid. The fluid inlet and the fluid outlet are positioned such that liquid flowing therebetween is passed through the filtering medium. A pump is fluidly connected between the pre-filtration apparatus and the main filtration apparatus. The pump has a suction side and a discharge side. A pre-filter control assembly is fluidly connected between the pre-filtration apparatus and the pump. The pre-filter control assembly has a normal operation setting wherein the fluid outlet of the pre-filtration apparatus is fluidly connected to the suction side of the pump to draw liquid sequentially through the fluid inlet of the pre-filtration apparatus, and the filtering medium of the pre-filtration apparatus. The pre-filter control assembly is also provided with a back wash operation setting wherein the fluid outlet of the pre-filtration apparatus is fluidly connected to the discharge side of the pump to force liquid sequentially through the fluid outlet of the pre-filtration apparatus, the filtering medium of the pre-filtration apparatus, and the fluid outlet of the pre-filtration apparatus.

Dependencies are inferred from the claim text.