Method and apparatus to control the temperature of a wet pellet dryer

Claim 1

APPARATUS FOR PELLETING CARBON BLACK COMPRISING, IN COMBINATION: AN ELONGATED HORIZONTAL CYLINDRICAL DRUM ROTATABLE ABOUT IS HORIZONTAL AXIS; A CONDUIT FOR ADDING FINELY DIVIDED CARBON BLACK TO SAID DRUM; A CONDUIT WITH RATE-OF-FLOW MEASURING DEVICE FOR ADDING AQUEOUS MOLASSES SOLUTION TO SAID DRUM; A CONDUIT T O PASS PELLETS FROM SAID DRUM TO THE INLET END OF A SECOND ELONGATED CYLINDRICAL DRUM HAVING AN INLET END AND AN OUTLET END AND ROTATABLE ABOUT ITS HORIZONTAL AXIS; A DEAD-TIME DELAY SIMULATOR TO RECEIVE A SIGNAL FROM SAID RATE-OF-FLOW MEASURING DEVICE WHICH IS PROPORTIONAL TO RATE-OF-FLOW OF AQUEOUS MOLASSES SOLUTION FLOWING INTO THE FIRST-MENTIONED DRUM; A LIMITING RELAY WITH PREDETERMINED HIGH AND LOW SET POINTS TO RECEIVE A SIGNAL FROM SAID DEAD-TIME DELAY SIMULATOR; AND A FLOW-RATE CONTROLLER RECEIVING A SIGNAL FROM A RATE-FLOW MEASURING DEVICE ON A CONDUIT FOR PASSING COMBUSTIBLE GAS TO BURNERS POSITIONED SO AS TO HEAT THE SECOND-MENTIONED DRUM ADJACENT ITS INLET END, SAID LIMITING RELAY BEING ADAPTED TO REGULATE THE SET POINT OF SAID FLOW-RATE CONTROLLER WHICH ACTUATES A FLOW CONTROL VALVE ON SAID CONDUIT FOR PASSING COMBUSTIBLE GAS TO SAID BURNERS; TEMPERATURE-MEASURING CONTROL MEANS FOR MEASURING THE TEMPERATURE ADJACENT SAID OUTLET END; AND MEANS FOR SUPPLYING SUFFICIENT HEAT TO SAID SECOND DRUM ADJACENT SAID OUTLET END CONTROLLED BY SAID TEMPERATURE-MEASURING CONTROL MEANS TO MAINTAIN THE TEMPERATURE OF THE DRIED PELLETS ADJACENT SAID OUTLET END AT A SUBSTANTIALLY CONSTANT PREDETERMINED TEMPERATURE.