Waste disposal process for spent wood-pulping liquors
Abstract
Abstract WASH WATER AND DIGESTER LIQUOR FROM A WOOD PULPING OPERATION ARE HEATED AT A TEMPERATURE IN THE RANGE OF 450*F. TO 700*F. UNDER AUTOGENEOUS PRESSURES OF ABOUT 1000 TO ABOUT 3000 P.S.I.G. FOR A PERIOD OF 0.5 MINUTE TO 6 HOURS TO FORM COKE AND A PURIFIED EFFLUENT. THE COKE IS SEPARATED FROM THE EFFLUENT AND DEWATERED. LIQUID FROM THIS DEWATERING STEP IS COMBINED WITH THE EFFLUENT AND DEPRESSURED TO FLASH VAPORIZE AND CONCENTRATE THE COMBIMED STREAM TO A SOLUBLE CHEMICALS CONCENTRATION SUITABLE FOR RECONSTITUTION AND RECYCLE TO THE PULPING OPERATION. COKE PRODUCED IN THE PROCESS MAY BE BURNED AS PLANT FUEL AND THE ASH RECOVERED AND WORKED FOR CHEMICAL VALUES. THE LIQUID STREAM IS RECONSTITUTED FOR PULPING PURPOSES BY THE ADDITION THERETO OF PULPING CHEMICALS DERIVED, IN PART, BY BURNING THE COKE PRODUCED IN THE PROCESS.
Inventors
- 👤 William F Franz
- 👤 Howard V Hess
- 👤 Edward L Cole
Bibliographic Details
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