掺烧高炉煤气锅炉的热力计算研究

Research of Thermodynamic Calculation for Boiler Bended with Blast Furnace Gas

高炉煤气与煤粉混烧发电供热是利用高炉煤气的主要方式。对一台300 MW煤粉锅炉掺烧高炉煤气,在不同掺烧比例下的热力计算结果表明,随着高炉煤气掺烧比例的增加,炉膛辐射换热减少,烟道对流换热增加,锅炉热效率降低。当高炉煤气掺烧比例为20%时,炉膛辐射平均热负荷减少12.22%,烟道对流换热量增加24%,锅炉热效率降低2.74%。

Blending the blast furnace gas （BFG） with coal to generate power and heat is the main usage of BFG in our country. Blending BFG to a 300 MW boiler, the thermodynamic calculation in the condition of different blending ratio of BFG shows that with the blending ratio of BFG increasing, the radiation heat transfer of the furnace decreases, the convection heat transfer of the flue increases, the boiler thermal efficiency decreases. When the blending ratio of BFG is 20%, the radiative average heat load of the furnace decreases by 12. 22%, the convection heat transfer of the flue increases by 24%, the boiler thermal efficiency decreases by 2. 74%.