300MW循环流化床机组供热节能方案对比分析

Comparison Analysis of Energy-Saving Heat Supply Scheme for 300MW Circulating Fluidized Bed Power Units

为了应对近年来北方供热需求的不断增加,提出对现有300MW亚临界直接空冷机组进行供热改造。基于高背压乏汽供热和吸收式热泵这2种火力发电厂余热利用技术,通过对原有抽凝供热机组采用这2种余热利用方案进行热经济性计算与分析,确定了适合该电厂空冷机组的余热利用改造方案。结果表明,高背压供热和吸收式热泵这2供热改造方案节能效果显著,总煤耗量降低;且对比同一发电负荷下,高背压供热节标煤量比吸收式热泵供热的节标煤量多,最大供热面积和最大供热负荷更大。如在最大供热负荷下,高背压供热和吸收式热泵供热分别将供电煤耗降至168.9、197.2g/(kW·h);而在同一发电负荷下,高背压供热最大供热负荷比热泵供热多73.6MW,最大供热面积多133.8×10~4 m^3。

The heat supply retrofitting is carried out on existing 300 MW sub-critical direct air cooling units to meet the increasing heating demand in northern China.Two waste heat utilization technologies for power plants were introduced,namely high back pressure heat supply and absorption heat pump heat supply.Based on the economic analysis of two waste heat utilization schemes,the proper solution was determined for the direct air-cooling power unit.The results show that high back pressure heat supply and absorption heat pump heat supply both have remarkable energy-saving effect,decreasing the total coal consumption.For given load,the coal rate of high back pressure heat supply is even lower than that of absorption heat pump heating with the maximum heating area and heating load.Specifically,under the maximum heating load,the coal rate is reduced to 168.9g/(kW·h)and 197.2g/(kW·h)through high back pressure and absorption heat pump heat supply.Under the same power load,the maximum heating load and heating area of high back pressure heat supply are 73.6MW and 133.8×10~4 m^2 higher than those of absorption heat pump heating.