Process for low sulfide chemical recovery
Abstract
Abstract A PAPER PULPING AND CHEMICAL RECOVERY PROCESS IS DESCRIBED WHICH IS PARTICULARLY ADAPTED TO PULPING WITH HIGH SULFIDITY LIQUORS SUCH AS THOSE USED IN THE POLYSULFIDE PROCESS. THE SULFIDITY OF THE BLACK LIQUOR IS REDUCED BY REACTION WITH SODIUM BICARBONATE SLURRY TO RELEASE HYDROGEN SULFIDE FOR REUSE EITHER DIRECTLY OR INDIRECTLY IN THE PULPING PROCESS. THE RESULTING LOW SULFIDITY BLACK LIQUOR IS THEN BURNED IN THE NORMAL MANNER TO PROVIDE GREEN LIQUOR. SODIUM CARBONATE IS CRYSTALLIZED FROM THE GREEN LIQUOR AND USED TO PRODUCE THE SODIUM BICARBONATE WHICH IS REACTED WITH THE BLACK LIQUOR. THE REMAINING GREEN LIQUOR IS TREATED IN THE CONVENTIONAL MANNER TO PROVIDE FRESH COOKING LIQUOR.
Inventors
- 👤 Hugh Wharton Nelson
- 👤 Carl R Bozzuto
Bibliographic Details
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