温差对气液交叉流PM2.5去除效率影响

Influence of Temperature Difference on Gas-Liquid Cross Flow PM2.5 Removal Efficiency

针对过程工业尾气PM2.5污染问题,提出以废气废水构建交叉流界面,利用高温工业废气与低温废水之间形成温差发生传热捕集尾气中PM2.5。研究含PM2.5高温工业废气横掠错排降膜阵列的传热传质,分析气液温差对PM2.5去除效率的影响,理论推导PM2.5去除效率表达式,结果表明PM2.5去除效率随气液温差增加而增大。对直径3mm的降膜阵列,气体Reynolds数为140的实例计算显示,气液温差由20oC增加至80oC时,单排降膜阵列PM2.5去除效率由0.33%提高至0.66%,200排降膜阵列去除效率由48.5%提高至73.2%,由350排液柱群组成的分离通道整体去除效率可达到90%。对高温工业尾气横掠降膜阵列进行实验验证,理论分析与实验结果吻合良好。

For the process industry exhaust PM2. 5 pollution problem,this paper proposes to use waste gas and waste water to build cross-flow interface,by use of the temperature difference between the high temperature industrial waste gas and low temperature waste water to generate heat transfer to collect PM2. 5. The heat and mass transfer of high temperature industrial waste gas containing PM2. 5 that crosses staggered falling film array is studied. This paper analyzes the influence of gas-liquid temperature difference on PM2. 5 removal efficiency and derives the formula of PM2. 5removal efficiency in theory. The results show that the removal efficiency of PM2. 5 increases with the increasing of the temperature difference between gas and liquid. As to the staggered falling film array with the diameter of 3mm,the calculation for gas Renolds number of 140 shows when temperature difference between gas and liquid increased from 20 !C to 80 !C,the PM2. 5 removal efficiency of single-line falling film array is improved from 0. 33% to 0. 66%,and the PM2. 5 removal efficiency of200-line falling film array is improved from 48. 5% to 73. 2%,and the overall removal efficiency of separation channel composed of 350 lines liquid column group can reach 90%. The experiment test is performed for high temperature industrial exhaust crossing falling film array,and the experimental results are consistent with theoretical results.