Process for the mild oxidation of carbonaceous solids

Claim 1

IN THE MILD OXIDATION OF CARBONACEOUS SOLIDS WITH AN OXIDIZING GAS AT TEMPERATURES LOWER THAN THE TEMPERATURES AT WHICH THE COMBUSTIBLE CONSTITUENTS OF SAID SOLIDS BURN TO A SUBSTANTIAL DEGREE TO THEIR ULTIMATE COMBUSTION PRODUCTS, THE IMPROVEMENT WHICH COMPRISES MAINTAINING A SERIES OF DENSE TURBULENT BEDS OF SAID SOLIDS FLUIDIZED BY A GAS, SAID BEDS BEING POSITIONED AT SUCCESSIVELY LOWER LEVELS, CONTACTING THE SOLIDS IN EACH BED WITH THE OXIDIZING GAS AT SAID LOWER TEMPERATURE, INTRODUCING FRESH SOLIDS INTO THE UPPERMOST BED, REMOVING OXIDIZED SOLIDS FROM THE FIRST BED AT A POINT SUBSTANTIALLY ABOVE THE BOTTOM OF THE BED AND FLOWING THEM DOWNWARDLY INTO EACH LOWER BED IN SUCCESSION, REMOVING OXIDIZED SOLIDS FROM THE LOWERMOST BED COOLING A PORTION OF SAID WITHDRAWN SOLIDS BELOW SAID LOWER TEMPERATURE AND RETURNING SOLIDS SO COOLED TO ONE OF SAID BEDS POSITIONED ABOVE SAID LOWERMOST BED.