空冷机组低位能分级混合加热供热技术的应用及经济性分析

Application of Heat Supply Technology of Cascade Mixing Heating Using Low-grade Energy for Air-cooled Unit and Economic Analysis of the Whole Power Plant

针对某电厂空冷机组,提出采用“空冷机组低位能分级混合加热供热技术”进行供热改造。介绍了该供热技术改造方案及热力系统布置,并对空冷机组低位能分级混合加热供热技术与传统抽汽供热技术经济性进行了比较分析。结果表明:初末期(次寒期)的空冷机组低位能分级混合加热供热技术比传统抽汽供热技术的供热焓值低646.78kJ/kg(4号机)、574.58kJ/kg(1号机),每供1GJ热量消耗的平均标煤低19.75kg/GJ(4号机)、20.49kg/GJ(1号机)。严寒期的空冷机组低位能分级混合加热供热技术比传统抽汽供热技术的供热焓值低391.98kJ/kg(4号机)、319.78kJ/kg(1号机),每供1GJ热量消耗的平均标煤低12.45kg/GJ(4号机)、13.19kg/GJ(1号机)。运行表明该低位能分级混合加热供热技术改造的热力系统稳定可靠,经济效益显著,节能减排效果明显,具有广阔的推广应用前景。

In view of an air-cooled unit in a power plant,"heat supply technology of cascade mixing heating using low-grade energy for air-cooled unit"is put forward to improve the heat supply of air-cooled unit.This paper introduces the technical reform scheme of the cascade mixing heating system and the arrangement of the thermal system,and analyses the econnmy of the air-cooled unit with the traditional extraction steam heating technology with the heat supply technology of cascade mixing heating using low-grade energy.The results show that:the enthalpy of heating of the heat supply technology of cascade mixing heating using low-grade energy for air-cooled unit is 646.78 kJ/kg(unit4),574.58 kJ/kg(unit1)lower than that of the traditional extraction steam heating technology,the average standard coal consumed per 1GJ of heat of the heat supply technology of cascade mixing heating using low-grade energy for air-cooled unit is 19.75 kg/GJ(unit4),20.49 kg/GJ(unit1)lower than that of the traditional extraction steam heating technology at the begining and end of the period(sub-cold period).The enthalpy of heating of the heat supply technology of cascade mixing heating using low-grade energy for air-cooled unit is 391.98 kJ/kg(unit4),319.78 kJ/kg(unit1)lower than that of the traditional extraction steam heating technology,the average standard coal consumed per 1GJ of heat of heat supply technology of cascade mixing heating using low-grade energy for air-cooled unit is 12.45 kg/GJ(unit4),13.19 kg/GJ(unit1)lower than that of the traditional extraction steam heating technology at the severe cold period.The operation shows that this thermal system is stable and reliable with remarkable economic benefit and obvious effect of energy saving and emission reduction,so it has a broad application prospect in the field of the cascade mixing heating system.