摘要
为进一步提高介质阻挡放电降解甲醛的效率,并控制副产物的生成量,论文采用正负高压双脉冲电源对同轴式介质阻挡反应器供电,系统地研究了脉冲电压、脉冲重复频率、放电间隙、气体流量及初始质量浓度等影响因素对甲醛降解率及臭氧生成量的影响。实验结果表明,升高脉冲电压有利于甲醛的降解,当电压达到19kV时,电压继续升高对降解率的影响不大,而臭氧生成量随着电压的增加不断增大;放电间隙对甲醛的降解率有很大的影响,随着放电间隙的减小降解率增大,但放电间隙过小时,臭氧生成量较大;随着流量的增大,甲醛降解率降低;随着脉冲重复频率的增大,甲醛降解率增大,当脉冲重复频率达到60Hz时,继续增加脉冲重复频率,降解率增大不明显;在一定实验条件下,甲醛的初始浓度越大,降解率降低,而甲醛降解量增大并趋近于反应器的最大处理量。
To further improve the efficiency of formaldehyde degradation and controlling byproducts generation in dielectric barrier discharge,coaxial dielectric barrier reactor was powered by dual positive and negative high voltage pulse power,the experiment systematic studied pulse voltage,pulse repetition frequency,discharge gap,gas flow and the initial concentration influence on formaldehyde degradation rate and ozone generation.The results showed that elevated pulse voltage conducive to formaldehyde degradation,when pulse voltage U=19k V,little effect on the degradation rate with voltage continued to rise,while ozone generation increased with the increased voltage;Discharge gap had a great influence on formaldehyde degradation rate,degradation rate increased with the decreased of discharge gap,but discharge gap was too small,a large amount of ozone generation;As the flow increased,degradation rate decreased;The pulse repetition frequency increased,formaldehyde degradation rate increased,when the pulse repetition frequency was60Hz,continue to increase the pulse repetition frequency,the degradation rate of increase was not obvious;Under certain experimental conditions,the greater initial concentration,the lower degradation rate,while the amount of formaldehyde degradation increased and close to the maximum capacity of the reactor.
引文
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