【摘要】 采用k-ε双方程湍流模型和离散相模型对循环流化床烟气脱硫(CFB-FGD)一体化除尘器内气固两相流动进行了数值模拟,分析了气流均布板、气室结构形式和锅炉负荷等对改进前后一体化除尘器的流场分布、处理风量、阻力特性及颗粒相流动状况的影响规律。模拟结果表明,渐扩型滤袋室和一定开孔率的气流均布板可很好地改善除尘器内流场分布的均匀性,与一体化除尘器原型相比,改进型除尘器内的颗粒流动更加均匀,同时灰斗积灰对颗粒相均匀分散有一定的改善作用。不考虑粉尘堆积情况下,改进型一体化除尘器总阻力损失与锅炉负荷满足二次函数关系。更多还原

【Abstract】 This paper reports on a numerical simulation of two-phase(gas-solid)flow characteristics in an integrated bagfilter with circulating fluidized bed flue gas desulphurization(CFB-FGD). The two-equation turbulence model and discrete phase model(DPM) are used in this numerical study,in which the effects of flue gas distributor,chamber structure and boiler load on flow filed distribution,handling capacity,resistance properties,particle flow trajectory of original and modified integrated bag-filters are analyzed. Results of the simulation indicate that the uniformity of flow field distribution in the integrated bag-filter can be improved by diverging inlet flue gas duct and flue gas distributor with a certain opening ratio; the particle flow in the modified integrated bag-filter is more uniform compared with that in the original one,and fly ash deposition in the bag-filter’s hopper can enhance the particle flow distribution in the modified integrated duster;and the resistance loss of modified integrated bag-filter and the boiler load conform with the quadratic function when ash deposition on the surface of the filter-bags is not considered.更多还原