大型联合钢铁企业低中热值煤气发电综合利用的优化分析

大型联合钢企的副产品低、中热值煤气不是洁净高能燃料,由此建成的煤气蒸汽联合循环机组要比天然气机组效率低8%-10%,排放特性与BTG型机组类似,且有较高投入、较高维护成本、较低可用率及不能适应变负荷运行等,难以满足电网AGC的要求。分析了可燃用低中热值的各种常规容量下的BTG类型与GTCC类型发电机组的经济特性与技术特性,根据东南沿海燃料价格高昂的实际情况,认为对低热值煤气BFG,以350 MW以上大型混烧BTG方式发电是较优的,高炉煤气放散可以接近零、安全可靠、成本较低、排放较少、对各种波动的煤气流量适应性更强,有利于投资方与当地电网。对COREX工艺大型联合钢企,以GTCC为主力是较好的方案。对天然气价格较低、COG/LDG富余较多的地方,结果不同。建议大型联合钢企副产品低、中热值煤气发电,要因地置宜,要根据煤气富余量、燃料价格、用电需求、环境与气候、投资与维护、综合实际供电成本等诸方面综合论证,以得出理性的优化方案。

Optimization of power generation with low or medium calorific gas in large integrated iron and steel works

Low or medium calorific gas,a kind of by-product of large integrated iron and steel works,is not a clean and high energy fuel.Based on the fuel gas,a gas-turbine combine cycle(GTCC) power unit could be built.It is 8%-10% less efficient than the natural gas unit(NG-GTCC).Its emission characteristic is similar to that of the boiler-turbine-generator(BTG) type unit and it needs higher investment,higher maintenance cost and has lower availability.It is for the variable load operation and difficult to meet the g...