内分离循环沸腾床分离器的试验研究

本文提出了一种新型内分离循环床装置,其特点是在炉内直接分离循环,分离效率较高,阻力小,可用或不用专设循环道.并介绍了有风板面积为360×360mm~2,悬浮段截面为500×500mm~2的冷态试验台上18种模型的试验结果.推荐了合理的结构参数数据.当试料为沸腾炉悬浮段飞出的飞灰时,其分离效率最高可达92%左右,压降一般小于4mmH_2O.现已投入工业性试验.本文还介绍了该装置的流场与粒子浓度场的测定结果和用电子计算机进行数值解所求得的该装置所能分离颗粒的中位直径的结果.

Experimental Study on Internal Separator of Circulating Fluidized Bed Combustor

A new type of internal separator for circulating FBB system is described in this paper. The main advantages of the separator are high separation efficiency and low pressure drop. It can be put to use with or without a special circulating passage. Without any sealing device the particles separated from the separator can return easily to the lean phase or to the dense phase through a circulating passage. Experimental results of eighteen sets of model installed in two bench scale facilities at cold condition are described. The cross sections of the bed and the freeboard of one facility are 360 × 360mm2 and 500× 500mm2 respectively. Another facility with a cylindrical combustion chamber of inside diameter φ300mm was also used in the experiments. When the bed material used is flyash from the freeboard of a bubbling bed boiler, the separation efficiency may reach up to 92-97%, while the pressure drop is usually lower than 4mm H2O. Recently, a full scale internal separator has been put into test in a Fluidized Bed Boiler. It has been shown that there is a good prospect for this separator to be used to improve combustion efficiency. Typical axial, tangential and radial velocity profiles measured by a probe and the fields of particle concentration determined by optical , fibre devices above this separator in the freeboard are described in this paper. Computers are used to calculate the critical particle diameter.