双流化床送风特性对循环流率影响的试验研究

Experimental Study of the Effects of Air Supply Characteristics on Solids Circulation Rate in a Dual Circulating Fluidized Bed

颗粒循环流率是双循环流化床气化装置性能优化的重要因素,而给风特性是影响颗粒循环流率的主要参数之一。自行设计并搭建了双循环流化床冷态试验台,试验研究了两床给风特性对颗粒循环流率的影响,重点分析了提升管二次风特性对颗粒循环流率的影响。试验表明:物料固定粒径、固定静床高时,颗粒循环流率随着两床风速的增大而增加,二次风速超过一定值后,颗粒循环流率增加的趋势趋于平缓;提升管径向给入二次风比切向给入二次风时颗粒循环流率大;颗粒循环流率对二次风口高度变化敏感,二次风口布置在距布风板15 cm时比20 cm时颗粒循环流率明显增加;颗粒循环流率随着风口数目的增加稍有增加。

Solids circulation rate is an important factor in performance optimization of a dual circulating fluidized bed（DCFB） gasifier,and air supply characteristic is one of its influencing parameters.This paper designed and set up a DFCB cold-state test bed,and studied the effects of air supply characteristics on solids circulation rate,emphatically the effects of riser＇s secondary air characteristics.It is tested that in the case of a fixed material particle size and a fixed static bed height,solids circulation rate rises with the two beds air velocity increasing,and the increase of solids circulation rate tends to flatten when secondary air velocity surpasses a certain speed;the increase is larger when the riser supplies air radially than tangentially;solids circulation rate is sensitive to the secondary air outlet height change： it increases more remarkably when the height is at 15cm from the air distribution plate than at 20 cm;it also rises slightly with the increased number of air outlets.