| 摘要 |
PURPOSE:To keep an air preheater in high efficiency by a method wherein the dirt removing device is controlled in accordance with the amount of leakage of combustion air in the air preheater. CONSTITUTION:An oxygen concentration detector 1 for exhaust gas at the outlet of the boiler, the oxygen concentration detector 2 at the outlet of the air preheater and an airflow amount detector 4 are provided in order to detect the amount of leakage of air, which leaks from an air duct 5 at the entrance of the air preheater to the side of a flue duct 10 in the air preheater 6. The amount of leakage is obtained by operating these amounts by an operator 11. The specified value of the amount of leakage of air is specified by a function genertor 13 by the amount of leakage obtained by the operator 11, a load detected by a load detector 12 or the signals of amount of air, amount of fuel or the like. When the specified value is exceeded, it is decided that the air preheater is dirtied and the control of start, stop and the like of the dirt removing device 15 for the air preheater may be effected efficiently. |
