Production and use of sulfur dioxide

Claim 1

A PROCESS FOR THE PRODUCTION OF ELEMENTAL SULFUR FROM HYDROGEN SULFIDE BY REACTION OF A GASEOUS STREAM CONTAINING THE SAME WITH A GASEOUS STREAM CONTAINING SULFUR DIOXIDE PRODUCED BY COMBUSTION OF SULFUR WHICH COMPRISES: PRODUCING THE SECOND-NAMED GASEOUS STREAM SUBSTANTIALLY FREE OF MOLECULAR OXYGEN AND HAVING LOW ELEMENTAL SULFUR CONTENT BY (1) REACTING TO SUBSTANTIALLY COMPLETE CONSUMPTION OF ITS OXYGEN CONTENT WITHIN A POOL OF LIQUID SULFUR MAINTAINED AT AUTO-INGITION TEMPERATURE BELOW 700* F. A STREAM OF OXYGEN-CONTAINING GAS ADMITTED TO SAID POOL AND (2) MAINTAINING SAID POOL AT THE AFORESAID TEMPERATURE BY CONTINUOUSLY WITHDRAWING LIQUID SULFUR FROM THE POOL, COOLING THE LIQUID SULFUR WITHDRAWN TO BELOW AUTO-IGNITION TEMPERATURE, RETURNING THE COOLED SULFUR TO SAID POOL, AND EFFECTING SAID WITHDRAWAL AND RETURN OF SULFUR AT RATE IN EXCESS OF ABOUT 25 TIMES THE RATE OF SULFUR COMBUSTION TO ABSORB AT LEAST A MAJOR PORTION OF THE HEAT OF COMBUSTION; COOLING THE COMBUSTION PRODUCTS BY DIRECT CONTACT OF THE SAME WITH A STREAM OF CIRCULATING COOLED LIQUID SULFUR TO CONDENSE FROM SAID COMBUSTION PRODUCTS SUBSTANTIALLY ALL OF THE SULFUR VAPORS CONTAINED THEREIN; REACTING THE FIRST- AND SECOND-NAMED GASEOUS STREAMS UNDER CONDITIONS TO FORM A GASEOUS PRODUCT CONTAINING ELEMENTAL SULFUR; COOLING SAID GASEOUS PRODUCT AND EXTRACTING ELEMENTAL SULFUR THEREFROM BY CONTACT WITH A STREAM OF CIRCULATING COOLED LIQUID SULFUR; AND WITHDRAWING AS THE SULFUR PRODUCT OF THE OPERATION A PORTION OF THE CIRCULATING COOLED LIQUID SULFUR.