| 摘要 |
PROBLEM TO BE SOLVED: To prevent corrosion of a heat transfer body by raising the entrance air temperature of an air preheater by mixing boiler exhaust gas with the entrance air of the air preheater. SOLUTION: A boiler device comprises a boiler 1 for generating vapor by combusting a fuel, a regenerative air preheater 2 for conducting heat exchange between an exhaust gas at a boiler exit and a combustion air of the boiler and a recirculating gas passage for feeding the exhaust gas to a boiler furnace. In the device, the entrance air temperature of the regenerative air preheater is controlled by mixing 6 the exhaust gas in the recilculating gas passage with the entrance air supplied to the regenerative air preheater. Furthermore, a fan 3 for raising pressure is provided to the recirculating gas passage so as to mix the exhaust gas at the fan exit side with the entrance air of the regenerative air preheater. |
