超声雾化增湿降温强化高比电阻粉尘静电收尘效果

The Effect of Humidifying and Cooling the High-resistivity Dust by Ultrasonic Atomization for Removing Dust in Electrostatic Precipitator

为了考查烟气温度及其水汽含量对静电除尘器除尘效果的影响,采用超声雾化对模拟气体加湿及电加热调控气体温度的方法进行了实验。实验测定气体工况条件下的流化床锅炉飞灰的比电阻。实测粉尘比电阻结果表明:当模拟气体温度在100~150℃区间变化时,水汽含量为23.73%条件下的粉尘比电阻值比水汽含量为5.21%条件时的比电阻值明显降低,尤其是在气体温度低于120℃时,比电阻值降幅更大,水汽含量为23.73%时对应的比电阻值可降低到10^(10)Ω·cm数量级;保持气体温度为150℃,增加气体中的水汽含量,粉尘的比电阻值虽然相应下降,但水蒸气含量增大为23.73%时,比电阻仍然超过1011Ω·cm。除尘效率测试结果表明:将模拟气体水汽含量增加到23.73%,气体温度低于120℃时,除尘效率显著提高。研究结果证实,通过烟气加湿及维持适宜的气体温度能够有效改善高比电阻粉尘的净化效率。

In order to investigate the effect of temperature and moisture content in the flue gas when removing dust by using electrostatic precipitator,experiments were processed by using ultrasonic atomization to humidify simulate gas and electric heating to control the gas temperature.The specific resistance of fly ash of fluidized bed boiler and the efficiency of dust removal has been tested in gas working conditions.The measured specific resistance of dust shows that when the temperature of gas at range of 100℃ to 150℃,the specific resistance of dust is lower when the air moisture is at 23.73%than which is at 5.21%,especially when the gas temperature is below 120℃,the specific resistance of dust reduce more,and it can reach the orders of magnitude at 10^10Ω·cm at the moisture of 23.73%;then keep the temperature at 150℃and make the moisture increased,the specific resistance of dust is decreased,however it is still more than 10^11Ω·cm when the moisture is increased up to 23.73%.The test result of the efficiency of dust removal indicated that：when we make the moisture increased to 23.73%and the gas temperature below 120℃,the efficiency of dust removal shows a significant increase.The results confirmed that we can improve the purification efficiency of high resistivity dust through flue gas humidification and proper temperature maintain.