Abstract: A two stage carbonizer places as much heat as possible into the gas streams entering the carbonizer to drive off volatile matter and reduce tars and oils by thermal cracking which is enhanced by the addition of sorbent. The carbonizer operates as a fluidized bed with a combustor providing flue gas as one fluidizing medium and preheated air as the other. This allows the coal to be devolatilized and the tars and oils to be thermally cracked due to the direct contact with the coal and hot flue gas. The device is designed to operate at high pressures from about 12-20 atmospheres.