荷电喷雾改善烟气脱硫效果的机理及试验  

Experiment and mechanism analysis on improving flue gas desulfurization efficiency by electrostatic spray

作　　者：王贞涛[1] 罗惕乾[1] 陈汇龙[1] 李庆利[1] 

机构地区：[1]江苏大学能源与动力工程学院,江苏镇江212013

出　　处：《排灌机械》2009年第6期403-408,共6页Drainage and Irrigation Machinery

基　　金：江苏高校自然科学基金资助项目(09KJD470001);江苏大学高级人才基金资助项目(09JDG067)

摘　　要：为了研究荷电喷雾对湿法烟气脱硫的增益作用,探讨荷电雾滴表面特性、荷电特性及运动特性与传质的关系,采用石灰浆荷电雾化的方法进行了荷电喷雾烟气脱硫试验,获得了不同液气比、Ca/S摩尔比和荷电电压下的烟气脱硫效率.结果表明:脱硫效率随着液气比、Ca/S摩尔比、荷电电压的增大而提高,且提高的趋势都在逐渐变缓,提高幅度最大为10%.高压静电场的存在改善了雾滴的表面吸收特性,增加了雾滴表面Ca2+的含量;荷电雾滴表面张力的减小降低了气体的传质阻力;雾滴带电及非过剩电荷感应极化作用,增加了雾滴吸收SO2的附加作用力;此外,高压静电作用下的二次雾化减小了雾滴粒径,增大了气液接触的总面积;带有同种电荷雾滴之间的相互排斥,雾滴在脱硫塔内部分布均匀.以上诸因素都有利于烟气脱硫效果的改善.In order to study the plus removal efficiency by electrostatic spray and discuss the relation of mass transfer and droplets surface, charge, and movement characteristics, the experimental investigation of flue gas desulfurization was carried out by electrostatic water and lime slurry spray. SO2 absorption efficien- cies with different liquid to gas ratios, Ca/S ratios and electrostatic voltages were obtained, and a maximum removal efficiency increment 10% was achieved. The results indicate that SO2 removal efficiency increases with the increasing of liquid to gas ratio, Ca/S ratio and electrostatic voltages adding, and the trend gradually becomes slower and slower. The high voltage field can improve the surface absorption characteristics and increase Ca2＋ concentration on the droplets surface. Droplets surface tension minishing can reduce the mass transfer resistance between the droplets and flue gas, and droplets electrification and non-excess charge polarization enhance the mass transfer impulse force of droplets absorption SO2. Moreover, the sec- ond atomization under high elestrostatic voltages can decrease the droplets diameter and add the reacting surface. The droplets can distribute uniformity in the tower for the droplets provided with the same polarity charge. SO2 absorption efficiency improvement is the complicated result from the above factors.

关 键 词：喷雾 荷电 烟气脱硫 脱硫效率 

分 类 号：TF054[冶金工程—冶金物理化学]