LCA Of Desulfurization Technologies Applied In Coal-fired Power Plants

SO2is a main pollutant in the flue gas exhausted from fossil fuel combustion in power station, which is removed by desulfurization equipment. In order to control SO2, the process will bring potential issues of material consumption, energy consumption and environment impact. In this study, wet limestone-gypsum and circulatory suspension type semidry de-SO2technologies were analyzed using the technique of life cycle assessment (LCA) to identify the environmental impact potential, with It SO2as a functional unit.The two de-SO2technologies were quantified over two life cycle phases: construction and operation in the paper. Firstly, construction process was analyzed. By using gabi software, lists of databases during the raw material acquisition, production and transportation processes were analyzed. In the same way, lists of operation process could be acquired. Summarizing the relevant lists, raw materials (iron ore, mineral resources, coal, oil and nature gas etc), water resource and air pollutants(CO2s CO、NOx、SO2)were identified.The paper used evaluation system EDIP97and EDIP2003to link the lists to environmental impact potential. We considered impact category of global warming, acidification, nutrient enrichment, photochemical ozone formation, waste water and solid waste.We found that by using the de-SO2technologies, acidification was well controlled. The environmental impact potential of construction process was much smaller than that of operation process. On the energy consumption and environment impact, circulatory suspension type semidry technology was better, because of wet limestone-gypsum’s high energy and water consumptions. And on the material consumption, wet limestone-gypsum technology was better, because of semidry technology’s higher Ca/S and the conversion efficiency of CaCO3to slaked lime.So, the technologies should take steps to reduce environment burden at relevant stages.