COMBUSTION OF BLACK LIQUOR AND PROCESSING OF LIME SLUDGE IN A RECOVERY BOILER

摘要

A method of modifying the course of combustion when evaporated black liquor is burnt in the furnace cavity of a recovery boiler is described. The method implies that lime sludge is supplied to the furnace cavity whereby the course of combustion is modified so that the temperature in the furnace cavity is raised. Also use of a recovery boil er for simultaneous combustion of black liquor and processing of lime sludge is described. In one embodiment of this use is disclosed that the processing of lime sludge is performed so that increased formation of calcium sulphide in the smelt of inorganic chemicals, which is formed in the recovery boiler, is obtained and/or so that the lime sludge is calcined.