350MW超临界机组凝汽器分区供热技术的经济性分析

Analysisof Economy on Partition Heating Technology of the Condenser for 350MW Supercritical Unit

为了提高高背压供热技术的适应性,针对某电厂350MW超临界机组供热需求,提出采用"凝汽器分区供热技术"进行改造的研究方案,介绍了该技术的供热系统布置,并与改造前的常规抽汽方案进行了详细的经济性计算对比。结果表明:严寒期,在额定工况且相同的供热负荷下,发电负荷由改造前的273.4 MW升高到306.11 MW,增加了32.71 MW,1 GJ供热量消耗的标煤由改造前的21.16 kg/GJ降至12.12 kg/GJ,降低了9.04 kg/GJ,发电煤耗率由改造前的225.47 g/(kW·h)降至201.36 g/(kW·h),降低了24.11 g/(kW·h);非严寒期,在额定工况且相同的供热负荷下,发电负荷由改造前的296.99 MW升高到329.66 MW,增加了32.67 MW,1 GJ供热量消耗的标煤由改造前的21.34 kg/GJ降至8.28 kg/GJ,降低了13.06 kg/GJ,发电煤耗率由改造前的248.58 g/(kW·h)降至224.81 g/(kW·h),降低了23.77 g/(kW·h)。

In order to improve the adaptability of heating technology of high back pressure,to satisfy the heating requirement on 350MW supercritical unit of a ceration power plant,a research scheme of"partition heating technology of the condenser"was proposed.An introduction to the arrangement of heating supply system in this novel technology was presented,while a comparison of economy was made between the conventional before transformation and the proposed heat supply mode based on detailed calculation.The results showed that:the generation load increased from 273.4 MW before the transformation to 306.11 MW,an increase of 32.71 MW,the standard coal consumed per 1 GJ of heat decreased from 21.16 kg/GJ before the transformation to 12.12 kg/GJ,a decrease of 9.04 kg/GJ,and the coal consumption for power generation decreased from 225.47 g/(kW·h)before the transformation to 201.36 g/(kW·h),a decrease of 24.11 g/(kW·h),in the same heating load under rated condition at the severe cold period.The generation load increased from 296.99 MW before the transformation to 329.66 MW,an increase of 32.67 MW,the standard coal consumed per 1 GJ of heat decreased from 21.34 kg/GJ before the transformation to 8.28 kg/GJ,a decrease of 13.06 kg/GJ,and the coal consumption for power generation decreased from 248.58 g/(kW·h)before the transformation to 224.81 g/(kW·h),a decrease of 23.77 g/(kW·h),in the same heating load under rated condition at the non-frigid period.