循环流化床锅炉燃煤技术热电厂生命周期评价

Life cycle assessment of thermal power plant based on circulating fluidized bed combustion technology

运用生命周期评价方法,应用Gabi5.0软件对采用循环流化床锅炉燃煤技术的热电企业进行资源耗竭和环境影响分析,计算各生产单元生命周期清单的全球变暖潜值、酸化效应潜值、富营养化潜值、非生物资源耗竭潜值、人体毒性潜值以及光化学烟雾和臭氧生成潜值等主要环境影响类型,对燃煤发电过程进行生命周期评价。结果表明,全球变暖和非生物资源耗竭为发电运行过程中主要的环境影响因素,分别占53%和15.05%;锅炉燃烧阶段的环境影响最重,占整个生命周期影响值的77.12%,并且除生物耗竭潜值外的其他5项指标均为发电运行阶段各个单元中最高。采用SNCR脱硝技术减少燃烧过程中NOx的排放量,并对该技术方案进行生命周期评价,比较方案实施前后的环境影响。

Method of life cycle assessment(LCA) was applied to evaluate the resource depletion and environmental impact potential of a thermal power plant employing circulating fluidized bed(CFB) combustion technology.A life cycle assessment model was constructed using Gabi5.0 software to calculate global warming potential(GWP),acidification potential(AP),abiotic depletion potential(ADP),eutrophication potential(EP),human toxicity potential(HTP) and photochemical ozone creation potential(POCP).The results indicate that GWP and ADP are two main environmental impact factors in the power generation process,with the contribution proportion of 53% and 15.05%,respectively; environmental impact of boiler combustion is the highest among five units,occupying 77.12% of the whole life cycle impacts,with the highest value of GWP,AP,EP,HTP and POCP in all of the six indexes.SNCR can be used to reduce NOxemission of CFB boilers in the research and LCA theory is used to evaluate the environmental influence after using SNCR to compare with the former process.