分离器性能对循环流化床锅炉启动过程中床料动态平衡的影响

Effects of Separator Performance on Dynamic Balance of Bed Material During Startup of CFB Boilers

通过建立循环流化床(CFB)锅炉启动过程中床料的动态平衡模型,研究了分离器效率、临界粒径d99和切割粒径d50对床料粒径动态分布、启动时间和平衡后床料粒径分布的影响.结果表明:d50和d99越小,分离器对不同粒径颗粒的分离效率越高,床料越细,床料质量越高;d50减小,床料动态平衡时间会延长;d99对床料动态平衡的影响反映在初始床料中粒径范围为d99到循环灰颗粒粒径上限的质量分数上,此质量分数越大,则动态平衡时间越短.

A dynamic model was set up for bed material balance in CFB boilers during startup process,so as to study the influence of separator efficiency,critical size d99and cut size d50on the bed material size distribution during and after dynamic balancing period,as well as on the startup time.Results show that the smaller the d50and d99,the higher the separation efficiency for particles of different sizes,the finer the bed material,the higher the quality of bed material;the dynamic balancing time increases with the reduction of d50.The effect of d99on dynamic balance of bed material is reflected by the mass fraction of particles in initial bed materials with the size ranging fromd99to the upper limit of circulating ash particles;the larger the mass fraction,the shorter the dynamic balancing time.