转底炉烟气脱硫脱硝技术路线的选择

Selection of Technical Route For Desulfurization and Denitrification of Flue Gas in Rotary Hearth Furnace

随着国家对大气环境保护的越发重视,钢铁行业超低排放的不断深入,转底炉项目污染物排放限值的要求也将进一步收紧。结合转底炉生产情况,分析其燃料特性和烟气污染物的生成机理,阐述了转底炉烟气处理的必要性、难点以及推动超低排放的合理化建议。基于对传统的烟气污染物控制技术进行综述,介绍了湿法脱硫、半干法脱硫、干法脱硫、选择性催化还原法和选择性非催化还原法等主流的烟气脱硫脱硝技术,从技术、投资和运行等多方面进行了对比探讨,为转底炉烟气脱硫脱硝新形势下超低排放技术路线的选择提供了一定的借鉴。转底炉烟气处置技术路线首选为“低氮燃烧器+SNCR+余热锅炉+SDS干法脱硫+布袋除尘器”,次选为“低氮燃烧器+余热锅炉+SDS干法脱硫+布袋除尘器+SCR”技术路线。

With the increasing attention of the state to atmospheric environmental protection and the deepening of ultra-low emissions in the steel industry,the requirements of pollutant emission limits for rotary hearth furnace projects will also be further tightened.Based on the production situation of rotary hearth furnace,the fuel characteristics and the formation mechanism of flue gas pollutants are analyzed,and the necessity and dfficulty of flue gas treatment of rotary hearth furnace are expounded.Based on the review of traditional flue gas pollution control technologies,the main flue gas desulfurization and denitrification technologies,such as wet desulfurization,semi-dry desulfurization,dry desulfurization,selective catalytic reduction and selective non-catalytic reduction,were introduced.The technology,investment and operation were compared and discussed.It provides some reference for the selection of ultra-low emission technical route under the new situation of flue gas desulfurization and denitrification of rotary hearth furnace.The flue gas disposal technical route of rotary hearth furnace is the first choice of"low nitrogen burner+SNCR+waste heat boiler+SDS dry desulfurization+bag dust collector",and the second choice is the technical route of"low nitrogen burner+waste heat boiler+SDS dry desulfurization+bag dust collector+SCR".