系统燃气轮机变工况对气化岛性能的影响 -

采用Thermoflex软件建立200 MW级IGCC系统模型,简要地对气化岛设计参数进行了分析,并对燃气轮机在100%～40%负荷下的气化岛变工况进行计算,分析比较气化岛主要设备性能参数的变化。结果表明:燃气轮机负荷降低时,在氧碳比不变的条件下,入气化炉的煤浆量和氧气量都减小,空分系统等耗功减少;废锅出口合成气温度、压力降低,废锅吸热功率也同时减少,废锅蒸汽做功能力下降;脱硫系统吸收塔入口合成气温度降低;燃气湿饱和器出口合成气压力降低,导致合成气中H_2O的体积分数减小,不利于减少NO_x排放。 A system model of 200MW IGCC is established with the Thermoflex software.Briefly analyze the design parameters of the gasification island.Off-design characteristics of the gasification island are mainly analyzed when gas turbine load varies from 100% to 40%.The results show that with the reduction of gas turbine load,the gasifier inlet parameters fall at constant O/C ratio and the power consumption such as air separation system reduces;at the same time the syngas temperatures out of the radiation syngas cooler,convective syngas cooler and the high-pressure economizer fall;besides heat absorption power,steam pressure out of waste heat boiler and the entrance temperature of the absorption tower in the desulfurization system decrease;syngas pressure out of syngas saturator decreases which lead to decrease in volume fraction of H_2O,and the syngas heating value increases which is no help for keeping down the NO_x