生物质直燃炉排炉运行问题分析与燃烧调整

Analysis of Operation Problems and Firing Regulation of A Biomass Direct-Fired Grate Furnace

某130 t/h生物质直燃联合炉排炉存在引风机出力不足、燃烧状况不佳、灰渣可燃物含量高等问题,现场测试表明引风机出力不足是由于一次风空气预热器和布袋除尘器烟气阻力增大引起。分析表明一次风空气预热器阻力偏大主要系烟气在受热面结露黏灰以及程控激波吹灰顺序不当除灰效果差所致,应调整激波吹灰器程控吹灰的投运顺序。对热一次风再循环提升风温能力不足,可进行热二次风加热冷一次风的技术改造。对入炉燃料掺配质量比例、配风方式、炉膛氧量和料层厚度及均匀性等进行调整,灰渣可燃物含量大幅降低,烟气中CO浓度显著下降,锅炉燃烧状况改善,效率提高。

A 130 t/h biomass direct-fired combined grate furnace had such problems as insufficient induced draft fan output,poor combustion,high mass content of unburned carbon in ash and slag,and so on.Field tests showed that the insufficient output of the induced draft fan was caused by the increase of flue gas resistance of the primary air preheater and the cloth bag collector.The high resistance of the primary air preheater was caused mainly by condensation of flue gas and dust deposition on the heater surface,and it was also caused by the poor dust removal effect of the program-controlled shock wave soot blowing sequence.The program-controlled shock wave soot blowing sequence should be regulated.Current hot primary air recirculation of the boiler was not enough to improve cold air temperature.The retrofit of the hot secondary air heating the cool primary air can be conducted.By regulating the mass ratio of fuels,air distribution,oxygen content of the furnace,the thickness and uniformity of fuels on the grate,etc.,the combustible contents in ash and slag and CO concentration in flue gas have been greatly reduced,the boiler efficiency has been improved.