脱硫废水蒸发脱除PM_(2.5)试验研究

Experimental Study on PM_(2.5) Removal with Evaporation of Desulfurized Wastewater

提出一种促进燃煤烟气PM_(2.5)团聚长大及脱硫废水处理的新方法。采用燃煤热态实验系统,在静电除尘器入口烟道进行脱硫废水蒸发试验,考察脱硫废水蒸发对飞灰物性、电除尘性能的影响,以及添加化学团聚剂、喷嘴的粒径对脱硫废水蒸发脱除PM_(2.5)的影响。结果表明:脱硫废水蒸发后,烟气细颗粒物粒径由0.15增加到1.0μm左右;典型工况下,电除尘前蒸发脱硫废水提高PM_(2.5)脱除效率约10%;脱硫废水加入团聚剂,电除尘出口PM_(2.5)脱除效率提高25%以上;降低喷嘴粒径、增加团聚剂添加量均有利于PM_(2.5)团聚长大。

A PM2.5 agglomeration technique was developed to control PM2.5 emission and treat desulfurized wastewater. The removal of PM2.5 by electrostatic precipitator （ESP） with evaporation of desulfurized wastewater was investigated experimentally based on a coal-fired thermal system. Effects of wastewater evaporation on fly ash, electric performance were analyzed, and chemical agglomerants and nozzle diameter were considered as two affecting factors. The results show that the average particle diameter increases from 0.15 to 1.0μm after evaporating desulfurized wastewater. The PM2.5 concentration at ESP outlet decreases by more than 10% under typical conditions. With the addition of agglomerants, PM2.5 concentration at ESP outlet decreases by more than 25%. Raising temperature, reducing nozzle diameter and increasing chemical agglomerant amount have a positive effect on PM2.5 removal.