公开(公告)号：US3841961A

公开(公告)日：1974-10-15

申请号：US21278671

申请日：1971-12-27

Applicant: TAMPELLA OY AB

Inventor： SAIHA E

IPC: D21C11/00 ,  D21C11/06

CPC classification number: D21C11/0071 ,  Y10S423/03

Abstract: REACTIONS IN THE RANGE OF ABOUT 25* TO 40*C.; REMOVING CARBONATED SOLUTION FROM THE TOWER.
1. A METHOD FOR THE CARBONATION OF SULPHIDE-CONTAINING GREEN LIQUOR SOLUTIONS OBTAINED FROM THE RECOVERY SYSTEMS OF PULP MILLS USING SODIUM BASE DIGESTION COMPRISING PASSING GREEN LIQUOR SOLUTION THROUGH AN ABSORPTION TOWER COUNTER-CURRENTLY TO A FLOW OF CARBONATION GAS CONTAINING AT LEAST TWICE THE AMOUNT OF CARBON DIOXIDE THAT THE GREEN LIQUOR IS CAPABLE OF ABSORBING FEEDING SAID CARBONATION GAS INTO A LOWER PORTION OF SAID TOWER PACKED WITH CONTACT SURFACE INCREASING PACKING, CONTACTING SAID CARBONATION GAS WITH SAID GREEN LIQUOR IN SAID LOWER PORTION, SAID AMOUNT OF GAS BEING SUFFICIENT TO CONVERT THE SULPHITE CONTENT OF SAID SOLUTION TO BISULPHIDE, CARBONATE AND BICARBONATE WHILE LIBERATING A MINOR PORTION ONLY OF SAID SULPHIDE CONTENT AS HYDROGEN SULPHIDE ALLOWING UNABSORBED CARBON DIOXIDE AND SAID LIBERATED HYDROGEN SULPHIDE TO PASS UPWARD INTO AN UNPACKED UPPER PORTION OF SAID TOWER, SPRAYING FURTHER FRESH GREEN LIQUOR SOLUTION FROM ABOVE SO THAT FINE DROPLETS OF GREEN LIQUOR SOLUTION CONTACT THE GASES RISING IN THE UNPACKED UPPER TOWER PORTION, SELECTIVELY REABSORBING SUBSTANTIALLY ALL OF SAID HYDROGEN SULPHIDE IN SAID FRESH GREEN LIQUOR SOLUTION AS BISULPHIDE; MAINTAINING A TEMPERATURE FAVOURABLE TO THE