COMBUSTION AIR SYSTEM FOR RECOVERY BOILERS, BURNING SPENT LIQUORS FROM PULPING PROCESSES

摘要

An arrangement is disclosed for supplying an air jet form to the furnace of a recovery boiler, where the furnace has a front wall, a rear wall and side walls. Black liquor spraying devices are disposed on the furnace walls at one or several levels of the furnace. I addition a plurality of air ports are located on several horizontal levels for introducing air into the furnace from an air supply. In the arrangement for the secondary air flows two horizontal air levels at different elevations are arranged above the lowest air level or levels and below the black liquor spraying level or levels. Air is supplied from two opposite walls on said two levels and the air ports are located so that the air jets are introduced in an interlaced pattern having an even number of jets on one opposite wall and an uneven number of jets on the other opposite wall. The air jets of said at least two air levels are located substantially one above each other in substantially vertical rows.