RECOVERY BOILER WITH ROTATING SECONDARY AIR BELOW AND A CONSTRICTION ABOVE THE LEVEL AT WHICH THE LIQUOR IS INJECTED

摘要

The invention relates to a recovery boiler for combusting spent liquour from cellulose cooking while at the same time recovering chemicals. The recovery boiler is constructed for so-called "rotafire" combustion and the speed of rotation of the secondary air has been increased by a constriction of the boiler being arranged at the tertiary air level (10). The invention also includes a process for using the boiler which is based on certain ports (11) through which the secondary air is blown in being provided with air which is at a higher pressure than that at the other ports on the same level, thereby achieving a higher inflow velocity than from the other ports.