Theoretical And Experimental Study On Pulsed Corona Discharge Wet Compound Precipitation

With the development of the economy,coal,oil and other petrochemical energy consumption has shown a rapid growth trend.A large number of dust particles are generated after burning,and meanwhile the rapid development of the construction industry and the suppression of dust work ineffective also has brought a lot of building dust,causing serious environmental problems.The content of dust in the air soars,seriously damaging the physical and mental health of human beings,so the environmental pollution control work is imminent.In order to solve the problem of particulate removal matter in the air,this paper has developed a pulse corona discharge wet compound dust removal technology to combine the pulse corona discharge dust and wet dust removal technology,explored the internal mechanism of action of compound precipitation,and the factors of influencing the efficiency of dust removal were studied and analyzed.In this paper,the working mechanism of pulsed corona discharge wet dust removal is studied,and the movement behavior of water mist and dust particles in four stages:gas ionization,dust charge,directional movement and dust removal are analyzed.At the same time,the mechanism of pulsed corona discharge,the charging mechanism of particulate matter and the charging mechanism of water mist are analyzed and discussed respectively.The origin of electrons is explored and the origin is divided into four categories: Class 1: ionization of gases caused by relatively high velocity molecules;Class 2: emission electrons caused by photoionization;Class 3: Sub-electron emission;Class 4: electrons produced by field emission.According to whether the influencing factors in wet dust removal are controlled by human beings,the influencing factors are divided into controllable external factors and uncontrollable internal factors.Among them,the external factors include pulse voltage and water pressure,and the effect of water mist and ionic wind of uncontrollable internal on the process of dust collection and discharge is respectively discussed and analyzed in detail.According to the needs of the experiment,the wet electric dust test bench is designed and developed.The main components include power supply,spray,polarmatching and other test bench module,which can facilitate the controlling and changing of controllable external factors,while the measurement methods of measuring the wind speed by using Pitot tube and tilt and of calculating the dust removal efficiency by using weighing method are designed,which can realize the accurate measurement of the experimental results under different experimental parameters.The experimental process of the experimental study on controllable external experiment and comparative experimental study are designed.The flow field of the precipitator was simulated by using the software Fluent.The flow field distribution in these two cases(when the entrance wind speed is 15m/s and 20m/s)was studied.The simulation results show that the air flow velocity in flow field of the precipitator is in the scope of 0-3m/s,and velocity distribution is fairly uniform in most regional of the flow field.In the pulsed power supply mode,the experimental study on the controllable external factors such as water spray pressure,pulse voltage,dust volume and wind speed in dust removal is carried out respectively.The changing curves of dust removal efficiency under different controlled external factors are obtained,and the law of curve changing is studied.The optimum operating parameters are obtained as follows:the spray pressure is 0.4MPa,the supply voltage 60 KV,and the wind speed0.8m/s-1.2m/s.In this paper,the variation of dust removal efficiency under pulsed power supply and DC power supply is studied.Under the DC power supply mode,the changing curves of dust removal efficiency when changing the spray pressure DC voltage and wind speed is obtained,and the comparative experimental study with the changing curves under pulsed power supply mode is performed respectively.The experimental results show that the efficiency of pulsed power supply is always higher than that of DC power supply under different working conditions,which fully demonstrates the charging advantages of dust particles in pulsed power supply state,and the optimum operating parameters are the same in these two power supply modes.In addition,in order to further explain the effect of introducing wet dust in pulsed dust removal in improving the dust removal efficiency,this paper designed the comparative experimental study of wet electrostatic precipitator and dry electrostatic precipitator when pulsed power supply.The results show that the dust removal efficiency of wetelectrostatic precipitator is about 10% higher than that of dry electrostatic precipitator,fully illustrating the advantages of compound precipitation.