Ammonium sulfate production

Claim 1

A PROCESS FOR THE PRODUCTION OF AN IMPROVED GRANULAR AMMONIUM SULFATE WHICH COMPRISES INTRODUCING AN AMMONIUM SULFATE SOLUTION TO A SUBMERGED FLAME EVAPORATION ZONE, INTRODUCING COMBUSTIBLE MATERIAL TO SAID EVAPORATION ZONE, BURNING SAID COMBUSTIBLE MATERIAL IN SAID ZONE BELOW THE LIQUID LEVEL OF SAID AMMONIUM SULFATE AND THEREBY CAUSING THE REMOVAL OF WATER FROM SAID SOLUTION AND THE FORMATION OF SMALL CRYSTAL NUCLEI OF AMMONIUM SULFATE OF A LENGTH IN THE RANGE OF 1 TO 50 MICRONS, SAID CRYSTAL NUCLEI AND SAID SOLUTION FORMING A MAGMA, REMOVING A PORTION OF SAID MAGMA TO A THICKENING ZONE WHEREIN A PORTION OF THE SOLUTION IN REMOVED FROM THE CRYSTALS, RECYCLING THE SEPARATED SOLUTION TO SAID EVAPORATION ZONE FOR FURTHER EVAPORATION, REMOVING ANOTHER PORTION OF SAID MAGMA FROM SAID EVAPORATION ZONE AND COMBINING THEREWITH THE PREVIOUSLY THICKENED MAGMA TO FORM A CRYSTAL MAGMA OF HIGH CRYSTAL SOLIDS CONTENT, PASSING SAID MAGMA OF HIGH CRYSTAL SOLIDS CONTENT TO A MIXING ZONE WHEREIN IT IS ADMIXED WITH RECYCLE DRY AMMONIUM SULFATE IN SUCH QUANTITIES THAT THE MOISTURE CONTENT OF THE ADMIXTURE IS NOT MORE THAN 1 TO 10 WEIGHT PER CENT, THE CRYSTALS OF SAID MAGMA AND THE DRY AMMONIUM SULFATE ADHERING TO ONE ANOTHER IN SAID MIXING ZONE IN THE FORM OF GRANULES, PASSING SAID GRANULES FROM SAID MIXING ZONE TO A DRYING ZONE WHEREIN THEY ARE CONTACTED WITH A DRYING GAS TO REMOVE THE MOISTURE THEREFROM, SAID CRYSTALS BECOMING CEMENTED TO SAID RECYCLE AMMONIUM SULFATE BY THE REMOVAL OF SAID MOISTURE AND THE CRYSTALLIZATION OF THE AMMONIUM SULFATE FROM WHICH SAID MOISTURE IS REMOVED, PASSING SAID DRYING GAS TO A SEPARATION ZONE WHEREIN ENTRAINED AMMONIUM SULFATE FINES ARE REMOVED, PASSING SAID FINES TO SAID MIXING ZONE AS RECYCLE AMMONIUM SULFATE, SEPARATING SAID AMMONIUM SULFATE GRANULES FROM SAID DRYER AND SELECTING GRANULES OF A DESIRED SIZE, RECYCLING GRANULES OF TOO SMALL A SIZE TO SAID MIXING ZONE, PASSING GRANULES OF TOO LARGE A SIZE TO A CRUSHING ZONE AND CRUSHING SAME TO SMALLER SIZE, RECYCLING SAID CRUSHED AMMONIUM SULFATE GRANULES TO SAID MIXING ZONE, AND RECOVERING THE GRANULES OF DESIRED SIZE.