Process and apparatus for evacuating heavy solids from a decanter

Claim 1

A COMBINATION OF A DECANTER FOR SEPARATING HEAVY SOLIDS FROM A LIQUID SUSPENSION AND APPARATUS FOR EVACUATING SAID HEAVY SOLIDS FROM THE DECANTER, SAID DECANTER INCLUDING A CIRCULAR TANK, MEANS FOR INTRODUCING A LIQUID SUSPENSION OF HEAVY SOLIDS INTO SAID TANK, MEANS ADJACENT THE TOP FOR WITHDRAWING SOLID-FREE LIQUID FROM SAID TANK AND MEANS AT THE CENTER OF THE BOTTOM OF SAID TANK FOR WITHDRAWING HEAVY SOLIDS, SAID EVACUATING APPARATUS INCLUDING A VERTICALLY DISPOSED SUPPORT MEANS MOUNTED FOR ROTATION ABOUT THE AXIS OF SAID TANK, A PLURALITY OF RADIAL ARMS SECURED TO SAID SUPPORT MEANS AND EXTENDING OUTWARDLY IN SPACED RELATION ABOVE THE BOTTOM OF SAID TANK, A SPIRAL SCREW CONVEYOR ROTATABLY MOUNTED UNDER AT LEAST ONE OF SAID ARMS IN CLOSE PROXIMITY TO THE UPPER SURFACE OF THE BOTTOM OF SAID TANK AND TERMINATING AT THE INNER END ADJACENT SAID WITHDRAWING MEANS, A FLUID PRESSURE OPERATED MOTOR COUPLED TO THE OTHER END OF SAID CONVEYOR FOR DRIVING SAID CONVEYOR, SEPARATE DRIVE MEANS FOR ROTATING SAID SUPPORT MEANS TO TRANSVERSE SAID CONVEYOR OVER THE ENTIRE BOTTOM SURFACE OF SAID TANK WHEREBY SOLIDS RESTING ON SAID BOTTOM WILL BE MOVED INWARDLY INTO SAID WITHDRAWING MEANS, AND AN UPWARDLY EXTENDING FRAMEWORK CARRIED BY EACH ARM, THERE BEING A PLURALITY OF VERTICALLY SPACED, RADIALLY EXTENDING, ANGULARLY DISPOSED VANES CARRIED BY SAID FRAMEWORK, WHEREBY UPON ROTATION OF SAID ARMS AND FRAMEWORK ABOUT THE VERTICAL AXIS OF SAID TANK SAID VANES WILL SERVE TO URGE SOLIDS IN SUSPENSION DOWNWARDLY THEREBY ACCELERATING SEPARATION OF SAID SOLIDS FROM SAID SUSPENSION.