Process and apparatus for the removal of finely divided solid carbonaceous particles from fluidized carbonizers

Claim 1

IN A PROCESS FOR THE LOW TEMPERATURE CARBONIZATION OF COAL COMPRISING PREOXIDIZING FLUIDIZED FINELY DIVIDED COAL, CARBONIZING SAID PREOXIDIZED COAL IN A FIRST FLUIDIZED BED TO PRODUCE CHAR AND A STREAM OF GASEOUS HYDROCARBONS CONTAINING ENTRAINED SOLIDS, CONVEYING CHAR FROM SAID FIRST BED TO A SECOND FLUIDIZED BED, BURNING A PORTION OF THE CHAR IN SAID SECOND FLUIDIZED BED TO HEAT THE UNBURNED CHAR AND PRODUCE A STREAM OF GASEOUS PRODUCTS OF COMBUSTION CONTAINING ENTRAINED SOLIDS AND CONVERYING SAID HEATED UNBURNED CHAR FROM SAID SECOND BED TO SAID FIRST BED; THE IMPROVEMENT WHICH COMPRISES REMOVING AT LEAST A MAJOR FRACTION OF THE ENTRAINED SOLIDS FROM SAID GASEOUS HYDROCARBON STREAM AND RETURNING THEM TO SAID FIRST BED, REMOVING A MAJOR FRACTION, BUT A FRACTION SUBSTANTIALLY LESS THAN SAID FIRST-NAMED FRACTION, OF ENTRAINED SOLIDS FROM SAID GASEOUS PRODUCTS OF COMBUSTION STREAM AND RETURNING THEM TO SAID SECOND BED, WHILE RETAINING ENTRAINED IN SAID GASEOUS PRODUCTS OF COMBUSTION STREAM SOLIDS HAVING A SUBSTANTIALLY GREATER PARTICLE SIZE THAN THE SMALLEST PARTICLES REMOVED FROM SAID GASEOUS HYDROCARBONS, AND REMOVING THE PARTICLES RETAINED IN SAID GASEOUS PRODUCTS OF COMBUSTION FROM THE PROCESS.