Apparatus for pressure reduction on a flowing slurry

Claim 1

IN APPARATUS COMPRISING A VESSEL ADAPTED TO CONTAIN UNDER PRESSURE A SLURRY OF PARTICULATE SOLIDS SUSPENDED IN LIQUID MEDIA, SAID VESSEL HAVING AN INLET AND OUTLET, AND A CONDUIT CONNECTED TO SAID OUTLET, MEANS FOR CONTROLLING THE RATE OF FLOW OF SAID SLURRY THROUGH SAID CONDUIT COMPRISING, IN COMBINATION, A FIXED RESTRICTION IN SAID CONDUIT, A FULL OPENING VALVE IN SAID CONDUIT BETWEEN SAID RESTRICTION AND SAID VESSEL, A REPEATING CYCLE TIMING MECHANISM CONTROLLING THE OPERATION OF SAID VALVE EXCLUSIVELY IN FULLY OPEN AND FULLY CLOSED POSITIONS, AND AUTOMATIC CONTROL MEANS OVERRIDING SAID TIMING MECHANISM FOR FULLY OPENING AND FULLY CLOSING SAID VALVE IN RESPONSE TO HIGH AND LOW VALUES RESPECTIVELY OF ONE OF TEH VARIABLES IN SAI VESSEL DIRECTLY AFFECTED IN INVERSE PROPORTION TO THE FLOW RATE OF MATERIAL FROM SAID VESSEL.