Improved method of regenerating sulphurous acid and waste heat from sulphite cellulose boilers

摘要

179,150. Zellstofffabrik Waldhof. April 27, 1921, [Convention date]. Pulp, preparation of.-In regenerating the waste heat and sulphurous acid from a system of sulphite cellulose boilers A, B-Y, Z, valves leading by conduit 4 to the tank 14 are opened and the pressure thus reduced to about 2 atmospheres. These valves are then closed, valves a' to z3 and 8 are opened, and cold fresh lye from a tank 7 flows along a conduit 5 and absorbs the remaining steam and sulphurous acid evolved by the boilers A, B-Y, Z, and is collected in the tank 14, where it is finally saturated to the desired degree with sulphurous acid. The lye may run by gravity from the tank 7, or may be forced from a lower tank 9 by a pump 11.