旋风-布袋复合除尘器优化和除尘效率的数值模拟

针对燃煤工业锅炉烟尘超低排放的要求，采用数值模拟方法，研究了旋风除尘器(A)和内部滤袋前无导流板(B)、有导流板(C)或开孔挡板(D)的几种旋风-布袋复合除尘器的流场。结果表明：除尘器C的流场较均匀，较高风速时压降低于除尘器B、D。进一步模拟了除尘器A、C的分级效率，发现对于粒径低于15 μm的颗粒，除尘器A去除率低于60%，除尘器C去除率高于97.8%。且复合除尘器占地小，滤袋寿命长，具有广阔的应用前景。上述数值模拟结果可为复合除尘器的优化设计提供参考。

Optimization of cyclone-bag composite dust collector and numerical simulation of dust removal efficiency

For the ultra-low emission of flue gas and dust from coal-fired industrial boilers, a numerical simulation method was used to study the flow fields of cyclone dust collector (A) and several kinds of cyclone-bag composite dust collectors without baffle (B), with baffle (C) or perforated baffle (D) in front of inner filter bag. The results showed that the flow field of cyclone-bag composite dust collector C was more uniform than others, and its pressure drop was lower than cyclone-bag composite dust collectors of B and D at a higher inlet velocity. The grading efficiencies of cyclone-bag composite dust collectors of A and C were further simulated, it was found that for particles smaller than 15 micrometers, the corresponding removal efficiency by cyclone-bag composite dust collector A was lower than 60%, while the corresponding removal efficiency by cyclone-bag composite dust collector C was higher than 97.8%. Moreover, with advantages of less space, lower filter bag load and longer cleaning cycle, the new composite dust collector has a broad application prospect. The results of above numerical simulation provide guidelines for the design and optimization of the composite dust collector.