百万燃煤机组烟气污染物超低排放改造费效评估

Economical assessment of ultra-low pollutants emission technology innovation for coal-fired power plants

随着我国火电厂大气污染物排放标准的日趋严格,燃煤发电企业陆续开展环保装备升级改造工作,其中部分燃煤电厂已完成大气污染物超低排放改造工作。目前,针对超低排放改造后的成本效益,仍缺乏系统性的分析及评估。基于大量电厂运行DCS及CEMS数据,以某百万燃煤机组烟气污染物超低排放技术改造的情况为实际案例,采用费用-效益分析的方法,对其展开超低排放技术运行经济性评估及研究。同时,结合情景分析,研究负荷、含硫量及年发电时间等关键影响因素变化对污染物脱除成本的影响。结果表明:改造后,污染物(SO_2、NO_x及PM)脱除成本比改造前增加约13~20元·(MWh)-1,约占上网电价的2.8%~4.4%。改造后,该电厂SO_2、NO_x及PM排放绩效分别达到0.048、0.109及0.007 g·(k Wh)-1,每年可产生环境效益约1 344万元。此外,提升机组运行负荷能显著降低污染物脱除装备运行成本从实际运行平均负荷(66%负荷)提高到满负荷运行,FGD、SCR脱硝及ESP+WESP除尘单位发电量运行成本分别可下降约30.5%、32.1%和38.1%。

As China is increasingly tightening the limits on the emissions of air pollutants from thermal power plants,several coal-fired power plants have been reconstructed with ultra-low emission technology. However,there is currently a lack of theoretical studies on how to apply cost-benefit appraisal analysis to ultra-low pollutant emission technology for coal-fired flue gas. Based on cost-benefit analysis,considering the influence of load,sulfur content,and annual generating hours to pollutant-removal rate,a modelwas constructed to evaluate the economic performance of a 1000 MW coal-fired power plant with pollutant control facilities that have been upgraded to ultra-low pollutant emission technology. The results show that the pollutant（ SO_2,NO_x,and PM）-removal cost increased by about 13—20 yuan·（ MWh）^-1,accounting for about 2. 8% —4. 4% of electricity prices. After technical updates,the environmental benefit clearly improved,since the pollutant emissions of SO_2,NO_x,and PM were reduced by 0. 048,0. 109 and 0. 007 g·（ k Wh）^-1due to technological,respectively. Therefore,the environmental benefit is 1. 344 million yuan per year. In addition,when the operating load of the unit is increased from 66% to 100%,then the operating costs of Flue Gas Desulfurization,Selective Catalytic Reduction,and Electronic Stability Program together with Wet Electro Static Precipitator would be reduced by 30. 5%,32. 1%,and 38. 1%,respectively.