Separation of solid substances from liquids

Claim 1

A CONTINUOUS ROTARY FILTERING DEVICE COMPRISNG IN COMBINATION A RELATIVELY LARGE DIAMETER CYLINDER OF FILTERING MATERIAL DEFINING A CYLINDRICAL FILTERING CHAMBER; A CASING SURROUNDING SAID FILTERING MATERIAL CYLINDER AND DEFINING THEREWITH A DRAINAGE SPACE; A LIQUID DISCHARGE OUTLET COMMUNICATING WITH SAID DRAINAGE SPACE; AND INLET AT ONE END OF SAID CHAMBER FOR INGRESS, UNDER PRESSURE, OF MATERIAL TO BE FILTERED; A CONCENTRATE DISCHARGE OUTLET AT THE OPPOSITE END OF SAID CHAMBER; A CYLINDRICAL BODY DISPOSED CONCENTRICALLY OF SAID FILTERING CHAMBER AND CMOUNTED THEREIN FOR ROTATIONAL MOVEMENT AT A SPEED EXCLUDING CENTRIFUGAL ACTION UPON THE MATERIAL PASSING THROUGH THE FILTERING CHAMBER; THE DIAMETER OF SAID BODY APPROACHING THE INTERNAL DIAMETER OF SAID FILTERING MATERIAL CYLINDER TO AN EXTENT SUCH AS TO PROVIDE SUBSTANTIALLY ONLY RUNNING CLEARANCE BETWEEN SAID BODY AND SAID FILTERING MATERIAL CYLINDER; AND A PLURALITY OF AXIALLY JUXTAPOSED BUT CLOSELY ADJOINING PARALLEL, HELICAL FLUTES EXTENDING ON THE CYLINDRICAL SURFACE OS SAID BODY THROUGH THE AXIAL EXTENT THEREOF, SAID FLUTES HAVING A SUBSTANTIALLY EQUAL AND CONSTANT WIDTH NOT EXCEEDING ABOUT ONE TWENTIETH PART OF THE DIAMETER OF SAID BODY AND A SUBSTANTIALLY EQUAL AND CONSTANT WIDTH NOT EXCEEDING ABOUT ONE TENTH PART OF SAID DIAMETER, WHEREBY MATERIAL ENTERING SAID INLET UNDER PRESSURE IS MOVED BY SAID FLUTES DURING ROTATION OF SAID BODY IN A PLURALITY OF SEPARATED NARROW AND SHALLOW HELICAL FLOWS TO SAID CONCENTRATE DISCHARGE OUTLET AND IS COMPRESSED BETWEEN THE SURFACE OF SAID FLUTES AND THE INNER SURFACE OF SAID FILTERING MATERIAL CYLINDER TO FORCE THERETHROUGH LIQUID FROM THE MATERIAL INTO SAID ANNULAR DRAINAGE SPACE; MEANS FORMING A RELATIVELY SMALLER DIAMETER SUBSTANTIALLY CYLINDRICAL COLLECTING CHAMBER EXTENDING COAXIALLY FROM THE DISCHARGE END OF SAID FILTERING CHAMBER; SAID CYLINDRICAL BODY HAVING A SMALLER DIAMETER CYLINDRICAL EXTENSION DISPOSED IN SAID COLLECTING DIAMETER CHAMBER AND FORMED WITH A PLURALITY OF AXIALLY JUXTAPOSED, PARALLEL AND RELATIVELY SHALLOW HELICAL GROOVES ON ITS CYLINDRICAL SURFACE AND EACH EXTENDING THROUGH THE AXIAL EXTENT THEREOF; SAID CONCENTRATE DISCHARGE OUTLET COMMUNICATING WITH THE AXIALLY OUT END OF SAID COLLECITNG CYLINDRICAL CHAMBER.