Sodium sulphite liquor recovery

Claim 1

THE PROCESS FOR REGENERATING SPENT LIQUOR FROM A SODIUM BASE SULPHITE TYPE WOOD PULPING PROCESS COMPRISING THE STEPS OF CONCENTRATING THE SPENT LIQUOR BY MULTIPLE EFFECT EVAPORATION TO AT LEAST SUBSTANTIALLY DOUBLE THE CENTRATING THE SPENT LIQUOR FROM SAID MULTIPLE EFFECT CONCENTRATING THE SPENT LIQUOR FROM SAID MULTIPLE EFFECT CONCENTRATING STEP TO A TOTAL SOLIDS CONTENT BETWEEN SUBSTANTIALLY 55% AND 7/% AND THEREAFTER BURNING THE FURTHER CONCENTRATED LIQUOR IN A FURNANCE TO OBTAIN CARBONATE AND SOAND SULFUR DIOXIDE CONTAINING FLUE GASES AND TO OBTAIN A FURNANCE SMELT WHICH INCLUDES SODIUM CARBONATE AND SODIUM SULFIDE, REMOVING SAID SMELT FROM SAID FURNANCE AND LEACHING SAID SMELT WITH WATER TO FORM GREEN LIQUOR, MIXING SAID GREEN LIQUOR WITH AN AQUEOUS SOLUTION OF SODIUM BICARBONATE TO FORM A HYDROGEN SULFIDE CONTAINING AQUEOUS SOLUTION OF SODIUM CARBONATE, STRIPPING THE HYDROGEN SULFIDE FROM SAID AQUEOUS SOLUTION OF SODIUM CARBONATE IN A TOWER BY CONTACTING CARBON DIOXIDE CONTAINING GASES DERIVED FROM SAID FLUE GASES THEREWITH AND THERAFTER PASSING THE STRIPPED HYDROGEN SULFIDE TO SAID FURNANCE, CONTACTING THE STRIPPED AQUEOUS SOLUTION OF SODIUM CARBONATE WITH CARBON DIOXIDE CONTAINING GASES IN ANOTHER TOWER TO FORM AN AQUEOUS SOLUTION OF SODIUM BICARBONATE RECYCLING A PORTION OF SAID AQUEOUS SOLUTION FOR SUCH MIXING WITH SAID GREEN LIQUOR, THERAFTER SULPHITING ANOTHER PORTION OF THE SODIUM BICARBONATE SOLUTION FORMED IN SAID OTHER TOWER BY CONTACTING SAID PORTION OF THE AQUEOUS