Characteristics Of Plasma Generation In Glow Discharge Of Laminated Electrodes And Research In Air Purification

With the continuous development of social economy,the problem of air pollution is becoming more and more serious.Plasma air purification technology generates a large number of free radicals,strong oxidizing particles,high-energy electrons,etc.by ionizing the air.It does not require consumables and has no secondary pollution.It can remove a variety of pollutants at the same time,and has high research value.In this thesis,a novel electrode structure is proposed to form a large-area glow discharge under atmospheric pressure air by constructing a stacked microelectrode.A variety of stacked microelectrode structures are proposed,and compared and optimized by electric field simulation.An indoor air purifier based on two stacked electrodes was developed,and the fluid simulation analysis and discharge experiment were carried out.An indoor air purification experimental platform was built to explore the effects of ozone catalyst and discharge module on the air purification effect.First of all,combined with the principle of micro-discharge,this study designs a linear laminated electrode,a mesh laminated electrode,and a foam metal laminated electrode.The electric field distribution of each electrode structure is simulated and analyzed to explore the difference and connection between the electric field distributions.Change their respective electrode parameters for electric field simulation analysis,and select the best parameters.The research on the metal foam laminated electrode found that,compared with the wire and mesh electrodes,the metal foam electrode not only has a high field strength area around the contact surface between the electrode and the insulating layer,but also has a longitudinal direction on the metal wire far from the contact surface.The high-field-strength region,that is,the high-field-strength region,is three-dimensionally distributed,which greatly increases the plasma generation area.Secondly,the overall design of the indoor air purifier is carried out.It mainly includes six parts: fan,primary filter module,air duct device,plasma discharge module,ozone treatment layer,and power module.Among them,two kinds of multi-electrode array discharge modules of wire-foam metal and plate-foam metal are designed.The velocity vector distribution fluid simulation of the airflow in the discharge module is simulated,and the optimal arrangement method is selected to achieve a good contact effect between the airflow and the electrode.The physical construction of the discharge module was completed,and a large area of the blue-violet light with good dispersion was generated at 1600 V,and the discharge current was at the milliamp level.In addition,an ozone treatment layer with supported manganese-based composite metal oxide as catalyst and modified porous activated carbon material as carrier was designed.Under the same voltage,comparing the change of ozone concentration before and after using the treatment layer,the ozone decreased by 81.7% for the wire-foam nickel electrode within two minutes;the ozone content for the plate-foam nickel electrode decreased by 89.7% within 10 minutes,reaching the better processing effect.Finally,an indoor air purification experimental platform was built,and the performance testing experiment of the purifier was completed.The formaldehyde and TVOC self-attenuation experiments were completed,and the attenuation was 5.97% and20.8% respectively in 60 minutes,which verified that the sealing effect of the purification chamber was good.The effect of ozone catalyst on the treatment effect was discussed,and it was found that the effect of glow discharge synergistic ozone catalyst in removing formaldehyde and TVOC was the best,the formaldehyde removal rate reached 100%,and the TVOC removal rate reached more than 90%.The treatment effect is second,and the treatment effect by the ozone catalyst alone is the second.This shows that the ozone treatment layer can improve the treatment efficiency of plasma decomposition of formaldehyde and TVOC,and the ozone removal method is feasible.The aldehyde removal effect of the two purifiers under the three treatment methods was compared,and it was found that the wire-foam nickel electrode had better effect and could achieve better treatment effect in a faster time.