Abstract: Comparative analyses were made on the strategies and technologies adopted by the industrialized countries for PM_2.5 emissions control during industrial development period.It is particularly recommended for China to take the experiences of 50% PM emission reduction as the target set by the Netherlands based on sufficient investigations of cost-effective strategies, corresponding to a concentration limitation of 9 mg穖^-3 waste gas from industrial sources.The emitted particulate matters, from the five highest emitting sectors of basic metal, refineries, chemicals, building materials and food processing, present the peak characteristics of PM_1.0 size distribution.Correspondingly the prior technologies for emission reduction are considered to be wet electrostatic precipitators or Wet-ESP alike.However they may not be a cost-effective option for China presently during the stage of basic industrial development in large scale.A novel approach of PM_2.5 removal through a temperature swing array of waste-gas and waste-water multi-phase cross-flow was proposed, employing fields of velocity, temperature and concentration generated in gas phase by heat and mass transfer crossing water columns to drive micron-particle moving towards gas-liquid interfaces.Each single water column became an independent PM_2.5 collection unit, which was regularly arranged in a series-parallel structure possessing high total efficiency of PM_2.5 collection.An experiment set-up, consisting of a cross-flow array with unit number n=200, was examined in site of a drilling rig to collect soot PM_2.5 from exhausts (4906 kg穐^-1 dry mass) of a 810 kW heavy duty diesel.The total collection efficiency was 91.4% as the model predicted, while the measured efficiency was slightly over 80%.It was proven, both by theory and practice, this approach of "waste-employed waste treatment" is highly cost-effective.

Key words: PM_2.5 emission reduction, wet collection, technology advances, temperature swing multi-phase flow, cross-flow array

摘要： 分析对比了工业化国家应对工业增长控制PM_2.5排放的策略与技术措施,特别是荷兰在充分的技术经济性研究基础上制定50% PM减排目标、相当于9 mg·m^-3工业尾气颗粒物允许排放浓度标准,值得我国借鉴。工业源颗粒物排放占比前5的冶金、石油加工、化工、建材和食品加工业颗粒排放物呈现PM_1.0的粒度分布峰值特征,应首选湿法静电沉降类(Wet-ESP)减排技术,但其经济性未必适合我国大规模基础工业发展阶段。提出废气-废水多相交叉流阵列变温脱除PM_2.5的新方法,利用气流横掠液柱传热传质产生的速度场、温度场和浓度场推动微粒向气液界面运动,使所有单液柱均成为独立的PM_2.5分离单元,其串-并联组合结构使阵列具有很高的PM_2.5分离总效率。模型预测单元数n=200的交叉流阵列用于810kW大功率钻井柴油机(排气量4906 kg·h^-1干气)尾气碳烟PM_2.5减排的效率为91.4%,现场模型试验实测值略大于80%,理论与实践均表明该方法以废治废、经济可行。

关键词: PM_2.5减排, 湿法除尘, 技术进展, 变温多相流, 交叉流阵列