US Patent 8142667 Manure separation for digester method and apparatus

A method and apparatus for removing settleable solids and unsettleable solids from a partially closed flush system in a dairy milking operation whereby a first processing tank bottom removes settleable solids contained therein where the net current flow vertically in the process tank is less than the settling rate of the settleable solids contained therein. The process tank batch feeds a plurality of thickening tanks that are each allowed to settle for a period of time before transferring fluid is to a second separator. The method and apparatus uses the solids for feeding a digester.