生物质直燃发电大气污染物超低排放技术路线分析

Analysis of technical route for ultra-low emission of air pollutants in biomass direct-fired power plants

总结了生物质燃料与煤的元素含量的差异,分析了生物质锅炉积灰、结渣、腐蚀的机理,梳理了生物质锅炉的烟气特点,并对选择性非催化还原脱硝技术、选择性催化还原脱硝技术、湿法脱硫技术在生物质电厂应用的局限性进行了讨论和总结。结果表明:固态高分子脱硝和催化剂脱硝脱硫均需特殊催化剂或脱硝剂,属于专利产品,运行成本高;氧化脱硝技术属于氧化吸收反应,产生易溶于水的硝酸盐,部分地区禁止采用该技术;陶瓷催化滤管一体化脱除技术运行维护简单,锅炉过氧燃烧可提高燃烧效率,延长空气预热器使用寿命,而且没有脱硫废水、烟囱防腐、白色烟羽等相关问题,适用于生物质锅炉硫、尘、硝超低排放。

The difference of element content between biomass fuel and coal is summarized,the mechanisms of ash accumulation,slagging and corrosion of biomass boilers are analyzed,and the characteristics of flue gas of biomass boilers are combed.Moreover,the limitations of selective non-catalytic reduction technology,selective catalytic reduction technology and wet flue gas desulfurization technology in the application of biomass power plants are discussed and summarized.The results show that,both the solid-state polymer NCR denitrification and sulfurnitrogen integrated removal using catalyst require special catalysts or denitrification agents,which are patented products and have high operating costs.The oxidation denitrification technology is oxidation absorption reaction,which produces nitrates that is soluble in water,this technology is prohibited in some areas.The ceramic catalytic filter tube integrated removal technology is simple to operate and maintain,of which the over-oxygen combustion of the boiler can improve the combustion efficiency and prolong the service life of air preheater.Moreover,there is no desulfurization wastewater,chimney corrosion,white plume and other related issues.Therefore,it is a more suitable for ultra-low emission of biomass boilers.