Self Scouring On Flue Gas Hmmidification And Flexible Electrode Experimental Study Of Wet Electrostatic Precipitator

The PM2.5 pollution is very serious in recent years and the atmospheric haze phenomena occurs frequently, coal-fired boiler of fine particulate matter is one of the main causes of the pollution. After the desulfurizer, the Coal-fired boiler flue gas can generate new particles. Plus the no removal of ultrafine particles in the front, the actual emissions of pollutants may exceed the current emission standard or fail to reach the ultra clean emissions. As a terminal control installation, wet electrostatic precipitator can effectively solve this problem. But the widely used wet electrostatic precipitator have large water consumption, difficult water treatment, uneven water film and some other problems. To solve these problems, this article adopted the way of flexible electrode, flue gas humidification and self-scouring wet electrostatic precipitator, then the removal process of fine particulate matter was studied.This article designed and built a lab-scale system of wet electrostatic precipitator that was characterized by flexible electrode, flue gas humidification and self-scouring. Then the wet electrostatic precipitator was debugged systematically and the effects of collecting plate and system operation parameters on collection efficiency of PM10, PM2.5 and total dust were studied.On the basis of predecessors’ study, this system added a venturi tube section in front of the wet electrostatic precipitator inlet duct and a twin fluid nozzle in its throat area for atomization hμmidification. Under the high-speed airflow, the mist were further atomized and evenly dispersed. The dust were trapped with droplet collsion in the process of droplet acceleration and the condensation rate increased gradually in diffusion section. Finally, the dust-droplets of large diameter formed and added the advantageous to the subsequent capture of wet electrostatic precipitator.Secondary voltage, wind speed, the amount of dust, collecting plates, volume of spray had influences on the total dust removal efficiency. With the increases of feeding quantities and wind speed, total dust removal efficiency was on the decline; With the increases of the secondary voltage and volume of spray, total dust removal efficiency was on the rise; The performance of collection plate 840A(polypropylene fiber) was slightly better than the collection plate 3927(terylene); Then through the analysis of the total dust removal efficiency formula under different situations, I found that the total dust removal efficiency was related to the number Deutsch number.Finally, the removal efficiencies of PM10, PM2.5 and grade removal efficiency were tested in this article. The minimums of removal efficiency had been found in 0.2 ~0.5μm and 2μm; The increase of wind speed added the number of removal efficiency of PM10 and PM2.5, but decreased the quality of removal efficiency; With the increase of the amount of dust, the removal efficiency of PM10, PM2.5 and grade removal efficiency increased in the beginning and then decreased. With the increases of the amount of spray and secondary voltage, the removal efficiencies of PM10 and PM2.5 and grade removal efficiency had gradually rising trends.