润湿剂促进燃煤细颗粒声波团聚脱除的实验研究

在声波团聚室中研究了润湿剂液滴与细颗粒碰撞团聚脱除特性,提出了一种利用润湿剂促进细颗粒在声波场中捕集的新方法。结果表明,不同润湿剂溶液对细颗粒在声波场中的团聚脱除效果存在较大差异,采用JFC和FS-310润湿剂溶液时,细颗粒分级脱除效率与采用水时的分级脱除效率相近。而SDS和Silanol w22溶液,则可有效提高细颗粒在各粒径段的分级脱除效率。细颗粒在声波场中的脱除效率与润湿剂润湿性能具有很好的相关性,随润湿剂对细颗粒相对接触角增大而降低,在声压级为150 dB时,相对接触角由83°降低到0°,细颗粒脱除效率提高了18%,在无声场作用下,脱除效率仅提高了5%。细颗粒脱除效率随声压级的增大而提高,在低声压级条件下,添加润湿剂可有效提高细颗粒脱除效率,声压级在130 dB时,添加SDS溶液液滴后细颗粒脱除效率比声场单独作用时的脱除效率提高了25%。表明添加润湿剂可有效提高细颗粒在声波场中的团聚脱除效率,实现在低声压级条件下,获得高的细颗粒脱除效率。

Experimental study on promotion of coal combustion fine particles acoustic agglomeration removal by using wetting agents

The characteristics of agglomeration removal between wetting agent droplets and fine particles were investigated in an acoustic agglomeration chamber. A novel technique using wetting agents to promote the fine particle capture by acoustic agglomeration was presented. The experimental results show that the type of wetting agent has a significant effect on the acoustic agglomeration of fine particles. The particle stage removal efficiencies using JFC and FS-310 are similar to that using plain water droplets, but the removal efficiencies by SDS and Silanol w22 are much higher than that using water droplets. Fine particle removal efficiency in the acoustic field correlates well with the wettability of wetting agents, which decreases with increasing the relative contact angle of wetting agents. While the relative contact angle descends from 83° to 0°, the removal efficiency of fine particles with sound pressure level of 150 dB increases by about 18%. However, the removal efficiency of fine particle without acoustic effects only increases by about 5%. Higher sound pressure level can improve the particle removal efficiency that is extremely low when the sound pressure level is below 150 dB. However it can be improved with wetting agents addition to the atomization droplets. The capture efficiency can be increased by 25% with SDS adding than acoustic effect only under the sound pressure level of 130 dB. It indicates that the removal of fine particles is effectively improved by using wetting agents with acoustic wave agglomeration, and the high removal efficiency can be achieved at a low sound pressure level.