燃煤超细颗粒物团聚促进机制的实验研究

Experimental study on agglomeration of submicron particles from coal combustion

煤粉燃烧排放大量超细颗粒物对大气环境和人类健康造成了严重的危害。提出一种燃后区烟尘团聚促进新方法,通过在燃后区烟道喷射团聚促进剂,利用絮凝理论,增加超细颗粒之间的液桥力和固桥力,促使超细颗粒物团聚长大,进而被现有除尘装置捕获,减少超细颗粒的排放。在自行设计搭建的团聚实验台上进行了系统的实验研究,分析了团聚促进剂溶液的pH值、流量、浓度,团聚室的温度以及模拟烟气中粉尘浓度等因素对超细颗粒物团聚效率的影响。结果表明,化学团聚对于超细颗粒物的脱除具有显著的作用,喷入团聚促进剂后的烟尘排放浓度远比无团聚和喷水的情况要低;团聚促进剂的高分子链对超细颗粒的吸附絮凝作用促进超细颗粒团聚,显著降低烟尘排放浓度,实现超细颗粒物经济高效脱除,达到国家新的烟尘排放标准。

The emission of submicron particles from coal combustion has caused serious damage to the environment and human health. A novel submicron particle agglomeration technique was developed to control the emission of submicron particle. The submicron particles were agglomerated by an agglomerant solution which was sprayed into the inlet of electrostatic precipitator （ESP）, thus, the agglomerated submicron particles could be captured by the dust collecting equipment. Systematic experiments of submicron particle agglomeration were conducted, and the influence factors including pH value, flow rate, and concentration of agglomerant solutions were analyzed. In addition, the influence of temperature and particles concentration in the simulated flue gas was also discussed. With the addition of the agglomerant solution, the particle emission concentration in flue gas decreased significantly. The submicron particles agglomeration technology whose cost is cheaper can control the emissions of submicron particles and decrease the opacity of flue gas obviously without changing the operation parameters of the ESP. The particle agglomeration technique is a useful and promising method to control the emission of submicron particles from coal combustion.