燃煤及其替代发电方案的生命周期评价

Life cycle assessment of coal-fired power generation and its alternatives

采用生命周期评价(LCA)方法对不同发电方案的环境性能进行了评价.从生命周期各阶段各污染物排放和环境影响潜值分析对比常规的燃煤发电(C-F)、整体煤气化联合循环(IGCC)和天然气联合循环(NGCC)发电系统的环境负荷.结果表明,针对要提高发电系统的环境性能问题,对燃烧发电阶段的PM,NOx和SOx的减排是C-F的有效途径;加强能源开采阶段的CH4和VOC的排放控制是NGCC和IGCC的有效途径;从环境影响指标酸化作用潜值(AP)和全球变暖潜值(GWP)来看,NGCC的环境效益最好;IGCC在酸性气体排放控制较C-F有明显改善,对IGCC扩展CO2回收工段实现温室气体减排,可明显改善全球变暖问题.综合考虑我国的能源结构状况,IGCC是适合我国的洁净燃煤发电方案.

Life cycle assessment （LCA） method was applied to analyze the environmental impacts of power generation scenarios. Environmental impact potentials of life cycle phases and emissions were calculated to compare conversional Coal-Fired （ C - F） to its alternatives Integrated Gasification Combined Cycle （IGCC） and Natural Gas Combined Cycle （NGCC）. Acidification Potential （AP） and Global Warming Potential （GWP） were taken as the environmental impact indicators. The results indicate that emission control should be taken in PM, NOx, SOx in fu- el combustion phase for C - F, and CH4, VOC control in fuel production phase for IGCC and NGCC ; for environmental impacts, NGCC performs the best, and IGCC performs better in AP than C - F; expending CO2 capture storage unit in IGCC can reduce GWP; IGCC is a clean coal power generation alternative in China.