液固循环流化床换热器中颗粒分布板分布性能的实验研究

The Performance Research of Distributor in Liquid-solid Circulating Fluidized Bed Heat Exchanger

设计了两种用于液固循环流化床换热器中的颗粒分布板,利用CCD图形采集与处理系统对液固循环流化床中的两相流动特性进行了研究.讨论了有无分布板、分布板开孔率、安装高度及操作条件对颗粒分布的影响.实验结果表明:在换热器下管箱安装颗粒分布板,当循环流速较高时,能有效的改善固体颗粒在床层中的不均匀分布;分布板的开孔率越小,固体颗粒径向分布的不均匀度越小,但床层颗粒浓度也变小;随着循环液速的增加,粒径的减小以及颗粒加入量的增加都会减小颗粒径向分布的不均匀度.

Two distributors in vessel in low of liquid-solid circulating fluidized bed heat exchanger were designed, two-phase flow propertied of liquid-solid circulating fiuidized bed was studied by CCD image measurement and data processing system. The influence about heterogeneous pores in distributor and fixing position to particles distribution was researched. The solid holdup and solid velocity in the tubes of the liquid-solid fluidized bed under different operating conditions and particle size were studied. Experimental results show that heterogeneous pores distributor can effectively improve the nonuniform distribution of particles in the pipe bundle under high flow rate. The nonuniform decreases by decreasing the mount of pore by the fixing position of the heterogeneous but the solid holdup decreases too. The particles distribution was influenced pores distributor.