DESULFURIZING METHOD FOR INSIDE OF FURNACE IN SOLID COMBUSTION FURNACE

摘要

PURPOSE:To enable to perform an efficient desulfurization even when applied to combustion exhaust gas, containing dust in a high concentration, of a solid fuel, by supplying a solid desulfurizing agent to a secondary combustion area of a reducing atmosphere. CONSTITUTION:Primary fuel and primary air are fed to the inside of a furnace from a burner 7, secondary air is fed from an air casing 8 to bring an air ratio to 1.0 or more, and a high-temperature primary combustion area (a) of an oxidation atmosphere is formed at the front part of the inside of the furnace. Secondary fuel is supplied to the inside of the furnace through a secondary fuel nozzle 9 to bring the air ratio to 1.0 or less, a slow reducing combustion is conducted to form a secondary combustion area (b) of a reducing atmosphere with temperature of 900-1,300 deg.C at the rear flow side of the primary combustion area (a), and in the area (b), a desulfurizing agent is fed to the inside of the furnace to conduct a desulfurization of the inside of the furnace. Moreover, tertiary air is supplied through a tertiary air nozzle 10 to form a tertiary combustion area (c) where residual fuel is burnt.