炉膛漏风对富氧煤粉燃烧锅炉烟气压缩系统运行特性的影响

Influence on Flue Gas Compression System Operating Characteristics of Oxy-coal fired Boiler from Furnace Air Leakage

以300 MW富氧煤粉燃烧锅炉烟气压缩系统为研究对象,计算和分析不同炉膛漏风系数的条件下,烟气压缩系统主要运行参数的变化规律。结果表明:随着炉膛漏风系数的增加,烟气压缩系统出口烟气中CO2的摩尔份额减少,增加了CO2捕集回收的能耗和难度;各级烟气冷却器出口烟温的增幅较小,系统中总析水量有所减少;烟气压缩机的流动损失增大,等熵效率下降,压缩功率增加,增加了烟气压缩系统运行的能耗。另外,炉膛漏风使烟气压缩机的压比增大,出口压力上升。

The flue gas compression system in a 300MW oxy-coal fired boiler unit was taken as an object of study. The change laws of main operation parameters in flue gas compression system were calculated and analyzed under the condition of different furnace air leakage coefficient. The results show that with the increase of furnace air leakage coefficient, the reduce of CO2 molar ratio of outlet flue gas in the flue gas compression system leads to the increase of energy consumption and the difficulty of CO2 capture and recovery; The increase amplitudes of all stages gas coolers outlet temperature are weak, but the total water breeding Mwater decreased in the system. The energy consumption of the flue gas compression system increases for the drop of the isentropic efficiency and the increase of the compressor power. In addition, the rise of the compressor pressure ratio leads to the rise of its outlet pressure.