Process and apparatus for recovery of powdered materials such as carbon black

Claim 2

A PROCESS FOR PELLETING CARBON BLACK COMPRISING PASSING POWDERED BLACK TO A PELLETING MILL AND PELLETING SAME; RECOVERING A PORTION OF THE EFFLUENT PELLET AS PRODUCT AND RECYCLING ANOTHER PORTION TO THE FEED END OF SAID MILL; PASSING AT LEAST A PORTION OF THE RECYCLED PELLETS, PRIOR TO INTRODUCTION TO SAID MILL, INTO AN UPPER SECTION OF A CARBON BLACK RECOVERY ZONE AND MAINTAINING A FLUIDIZED BED OF SAID PELLETS THEREIN; SPRAYING A LIQUID COMPRISING WATER INTO THE UPPER SECTION OF SAID BED SO AS TO WET SAID PELLETS; PASSING A GASEOUS SUSPENSION OF POWDERED CARBON BLACK UPWARDLY INTO THE BOTTOM OF SAID BED OVER ITS ENTIRE CROSS SECTION AND UPWARDLY THERETHRU SO AS TO MAINTAIN SAID BED IN FLUIDIZED CONDITION AND DEPOSIT POWDERED CARBON BLACK ON THE MOIST SURFACES OF SAID PELLETS; WITHDRAWING A STREAM OF THE SUSPENDING GAS FROM THE UPPER SECTION OF SAID RECOVERY ZONE; WITHDRAWING PELLETS FROM THE BOTTOM OF SAID RECOVERY ZONE AND PASSING SAME TO SAID MILL AS RECYCLE; SEPARATELY RECOVERING DUST FROM THE RECYCLED PELLETS FED TO SAID RECOVERY ZONE; AND INTRODUCING THE RECOVERED DUST TO THE FEED END OF SAID MILL.