Study On Purification Of Exhaust Gas From Spray Paint Process By Plasma Combined With Catalysis

In this paper,the research progress on the treatment of flue gas from painting is reviewed,including the pretreatment technology of paint mist and the purification of volatile organic compounds(VOCs).The paint mist pretreatment mainly includes wet process and dry processing method,VOCs purification technology includes traditional purification techniques,such as absorption,condensation and combustion methods,new purification technique,such as membrane separation,photocatalytic method,biological method,plasma purification method,describes the purification mechanism and processing technology and characteristics.In this paper,the theory of plasma technology,the technology of plasma coordinates catalysis and its reaction mechanism are introduced.In this study,we used a self-made dielectric barrier discharge(DBD)to produce non-thermal plasma.The DBD reactor was used to adsorb benzene,toluene and xylene.Firstly,a single treatment of low temperature plasma technology on simulated exhaust gas,including discharge voltage,current frequency,gas flow rate,inlet concentration of three benzene waste degradation rate;Secondly,different types of catalyst in the DBD reactor,relation of catalyst type and the degradation rate of organic waste gas;Last we perform the inspection of the cooperative the effect of catalyst and low temperature plasma of three benzene waste gas purification.Research shows that both the single use of plasma technology,and plasma assisted catalytic composite technology,the rate of degradation of benzene in the exhaust gas decreased with the increasing of inlet air flow rate and initial gas concentration and increased with increasing of applied voltage and discharge frequency;The purification efficiency of plasma synergistic catalytic composite technology is better than that of single plasma technology.The experimental results show that when the gas flow rate is 1.0L/min,the initial gas concentration is 207.9ppm,the applied voltage is 35kV,the discharge frequency is 110Hz,the energy utilization rate is up to 0.30mg/kJ.The addition of a certain amount of catalyst plays an important role in the degradation of waste gas,and the degradation effect of γ-Al2O3 is better than that of ceramic particles and 13X-molecular sieve.In the simulation of plasma assisted catalytic purification lacquering experiment,the waste degradation rate of three largest benzene can reach 95.04%under the condition of the optimization of inlet flow rate 1.0L/min,the gas concentration of 202.3ppm,applied voltage 35kV,discharge frequency 130Hz.