国外烟气脱硫技术应用进展

烟气脱硫是控制大气污染物排放、防止酸雨形成的重要措施。世界发达国家烟气脱硫技术成熟,应用较广。论述了常用的炼厂催化裂化装置烟气和热电厂锅炉烟气脱硫工艺的技术特点和应用情况。通过对炼厂催化裂化烟气脱硫常用的EDV技术、WGS技术、动力波逆喷塔技术等进行对比分析,认为EDV湿法洗涤技术压力降较小,对催化装置的各种事故工况有较强的适应性,能够实现长周期运行,预留的脱硝系统运行成本较高,建设周期短,占地面积小。WGS技术工艺建设周期短,占地面积小,由于需要大功率的循环浆液泵产生喷射流对烟气增压,在催化烟气携带大量催化剂等不正常工况下,对催化装置影响较大。动力波技术具有总投资费用和运行费用低,污水排放量少,占地面积小等优势。目前,在电厂烟气脱硫中技术较为成熟、应用业绩较好的脱硫工艺,主要有石灰石-石膏湿法、炉内喷钙法、半干法、氨法技术等,石灰石-石膏湿法脱硫工艺是最为成熟的烟气脱硫技术,国内外已有数百套装置投入商业运行,任何煤种均可采用这种脱硫方式,脱硫率高,单塔处理量大,对高硫煤、大机组更具有适用价值。

The Advances in Application of Flue Gas Desulfurization Technologies in Foreign Countries

Flue gas desulfurization is an important approach to controlling air pollutant emission and prevent- ing acid rain.In developed countries,flue gas desulfurization is a proven technology with wide applications.This article describes the technical characteristics and applications of commonly used technologies for removing sul- fur in the flue gas from catalytic crackers in oil refineries as well as flue gas from boilders in thermal pow- er plants.By comparing the EDV,WGS,and Dyna Wave inverse spray tower technologies,which are commonly used by refineries to remove sulfur in flue gas from catalytic crackers,the article thinks that the EDV wet washing technology has reletively low pressure drop,strong adapatability to various accident conditions of catalytic units,and enables long-term operation of the units.In addition,the reserved denitration system re- quires relatively high operating costs ,but the construction period of such system is short and the footprint of the system is small.The process construction period for the WGS technology is short and the system using this technology also has small footprint.As it requires the use of a high-power slurry circulating pump to produce a spraying jet to pressurize the flue gas ,under abnormal working conditions ,such as when catalytic flue gas carries a large amount of catalyst,the WGS technology will have a dramatic influence on the perfor- mance of catalytic units.The Dyna Wave technology has many advantages such as low total capital investment and operating cost,low sewage discharge,and small footprint.The main proven desulfurization technologies that have produced good results when used for removing sulfur in power plant flue gas include the limestone- plaster wet method,the in-boiler calcium injection method,the semi-dry method,and the ammonia process.The limestone-plaster wet method is the most mature flue gas desulfurization technology.Hundreds of commercial units using this technology have been in operation worldwide.This technology is suitable for any type of coal and has a high rate of desulfurization,with a high single-tower processing capacity.It is especially suitable for large sets of units processing high-sulfur coal.