Patent ID: 8133397

Claim:
A method of separating particulate matter from a slurry, comprising; providing a filter apparatus comprising a pressure vessel having a first end, a second end, and a substantially cylindrical wall portion defining a longitudinal axis of said filter apparatus, said pressure vessel defining an internal space; providing a first annular filter and a second annular filter within said internal space, said second annular filter surrounding said first annular filter, said first annular filter and said second annular filter defining an annular particulate collection volume therebetween, directing a flow of said slurry into said particulate collection volume under sufficient pressure to force fluid to flow in a substantially radial direction through said first annular filter and through said second annular filter and any of said particulate matter blocking a filtering surface of said first annular filter and said second annular filter to substantially fill said particulate collection volume with particulate; moving said first annular filter with respect to said second annular filter in a direction of said longitudinal axis upon completion of a filter cycle to allow said particulate to be emptied from said particulate collection volume.