飞灰循环流化床燃烧研究及其工业应用

Investigation of the Fiuidized Bed Combustion with Flyash Recycle and Its Industrial Applications

针对国内外流化床燃烧技术发展现状,提出了飞灰循环底饲回燃利用劣质煤的有效途径。在截面为285mm×285mm流化床燃烧试验装置上燃用京西无烟煤和常州贫煤的试验结果表明,采用飞灰循环技术后燃烧效率提高10％以上,Ca/S(摩尔比为)1.8时,脱硫效率达88％,随着循环倍率提高,燃烧效率和脱硫效率提高,床温和流化速度对燃烧效率的影响减弱,调节特性大为改善。文中还介绍了研制的35t/h无烟煤飞灰循环流化床锅炉的技术特色,并对其关键技术作了剖析。

An effective approach for utilizing low grade coals,fluidized bed combustion with flyash underbed recycle is recommended based on analyzing the state of the art of fluidized bed combustion.Experimental results firing western Beijing anthracite and Changzhou lean coal in a fluidized bed test rig of 285mm×285mm in cross section show that combustion effi- ciency increases by more than 10%,desulfurization efficiency reaches 88% for Ca/S mol ra- tio of 1.8,and that as recycle ratio increases both combustion efficiency and desulfurization efficiency increase,effects of bed temperature and fluidizing velocity on combustion efficiency are weakened,thus controllability is improved when flyash is recycled into the combustor. Specifications and technical features of the newly developed 35t/h FBC boiler firing anthra- cite with flyash recycle are given,and some key technical issues are analyzed.