INTERNAL CIRCULATION TYPE FLUIDIZED BED BOILER AND METHOD OF CONTROLLING SAME.

摘要

An internal circulation type fluidized bed boiler in which a fluidized bed primary combustion chamber is formed by providing above the portion of an air distributing plate from which the air having a higher mass velocity is ejected an inclined partition wall which is adapted to intercept an upward flow of the fluidization air ejected from this air ejection portion, and turn this upward flow of the air toward the position above the portion of the air distributing plate from which a gas having a low mass velocity is ejected, with a heat recovery chamber formed between the inclined partition wall and a furnace wall. The inclined partition wall is formed so as to have an angle of inclination of 10 DEG -60 DEG with respect to a horizontal plane, and a horizontal projection length of 1/6-1/2 of the horizontal length of the furnace bottom. The method of controlling this fluidized bed boiler consists of the steps of controlling the quantity of heat recovered from the heat recovery chamber in compliance with the request by the users of recovered heat by suitably regulating the flow rate of the air ejected from a diffuser for the heat recovery chamber, and controlling the feed rate of the fuel supplied to the fluidized bed primary combustion chamber, on the basis of the temperature of the fluidized bed primary combustion chamber.