化学团聚促进燃煤细颗粒物脱除的试验研究

Experimental Research on Fine Particles Removal from Flue Gas by Chemical Agglomeration

采用燃煤热态试验系统,进行了分别在电除尘器和脱硫塔入口烟气、脱硫液中添加化学团聚剂促进电除尘、湿法烟气脱硫系统脱除细颗粒物的试验研究;试验考察了团聚剂添加前后细颗粒物浓度及其粒度分布的变化,以及团聚剂类型、浓度、添加点烟温等对细颗粒物脱除效果的影响。结果表明:化学团聚技术可使细颗粒物平均粒径增大约4倍,数浓度降低40%以上;在电除尘器和脱硫塔入口烟气、脱硫液中添加化学团聚剂均可有效提高细颗粒物的脱除效果,其中在烟气中添加团聚剂的作用效果与添加点处烟温存在密切关系,高温烟气(250℃)中试验采用的有机团聚剂容易失效,而无机团聚剂仍能维持相同效果。

Experiments were conducted on an experimental coal-fired thermal system to study the removal of fine particles by electrostatic precipitator（ESP） and wet flue gas desulfurization（WFGD） system.Agglomerant solutions were added into flue gas and desulphurizing agents at the inlets of electrostatic precipitator（ESP） and desulphurization scrubber,respectively.Changes of number concentration and diameter distribution of particles were tested before and after the agglomeration,and the influences of species and concentration of agglomerant solutions,and the temperature of flue gas at the point of addition were analyzed.The results show that chemical agglomeration can increase the average size of particles by four times and decrease the number concentration of particles by 40%.Both the two addition sites of agglomerants have a positive effect on improving the removal of fine particles,and the performance of agglomerants added into flue gas has a close relationship with the temperature of flue gas.Organic agglomerant solutions have low efficiency in high-temperature（250℃） flue gas while inorganic ones can keep excellent performance.