COMBUSTION DEVICE OF COAL IGNITING BOILER

摘要

PROBLEM TO BE SOLVED: To provide a combustion device capable of performing a superior combustion of fine powder coal even when a boiler load is low. SOLUTION: There is a combustion device of a coal-igniting boiler comprising a longitudinal extended boiler for igniting fine powder coal acting as crushed fuel in an air stream; a plurality of burners installed at the boiler so as to inject the fine powder coal within the boiler; a heat exchanger installed at a heat transmitting section of a rear part of the boiler above the burners; a suction port arranged at the heat transmitting section of the rear part of the boiler to suck a part of combustion gas; a crusher for crushing fuel coal supplied to the burners; and a fine powder coal supplying line for transferring fine powder coal crushed by the crusher to the burners with the combustion gas. The burners are arranged in a vertical direction and, when there are many loads of the boiler, the fine powder fuel is supplied to the burners arranged from the upper side to the lower side. In turn, when a load of the boiler is low, the fine powder coal fuel is supplied to the burners arranged at the upper side.