填充床/沿面复合放电等离子体降解苯的研究

研究填充床/沿面复合放电等离子体反应器,用于对挥发性有机化合物(volatile organic compounds,VOCs)的降解.该反应器以置于石英介质管内的不锈钢弹簧为高压电极,以附着在有机玻璃管内壁的不锈钢网为低压电极,将石英介质管放于有机玻璃管中央,并于石英介质管外与低压电极间填充玻璃珠.采用交流高压电源供电,实现在石英介质管内发生沿面放电,同时在石英介质管外发生填充床放电.含污染物的气体首先通过沿面放电区域,然后经填充床放电区域排出.以苯为目标物,考察了高压电极弹簧外径、玻璃珠尺寸对苯降解的影响,通过引入MnO2/γ-Al2O3催化剂参与反应,进一步提高了苯的去除率.结果表明:在玻璃珠直径6 mm、高压电极弹簧外径12 mm、放电间距12 mm、放电电压27 kV、苯的初始体积分数为0.011 4%的条件下,苯的处理效率高达75%.MnO2负载量为MnO2/γ-Al2O3催化剂质量的10%,并填充于反应器底部,苯的降解率达85%,去除效果提高.

Benzene Degradation by Packed-bed/Gas Phase Surface Hybrid Discharge System Reactor

The degradation of volatile organic compounds,namely,benzene,by a packed-bed/gas phase surface discharge system reactor was investigated.A stainless steel spring closing to the wall of a quartz tube was used as high voltage electrode and low-field electrode was a piece of metal woven mesh which was close to the wall of an organic glass tube.In order to achieve gas phase surface discharge in the quartz tube as well as packed-bed discharge out of the quartz tube,the quartz tube was fixed in the center of organic glass tube and lots of glass beads were filled between quartz and metal woven mesh.High voltage alternating current power supply was used.Effects of diameter of high voltage electrode,glass beads and the MnO2/γ-Al2O3 catalyst were investigated.The results showed that removal efficiency of benzene was reached 75% under the conditions of using 6 mm glass beads,high voltage electrode diameter 12 mm,electrode distance 12 mm,voltage 27 kV and benzene initial volume fraction of 0.011 4 %.The degradation efficiency of benzene was further increased to 85% when adding MnO2/γ-Al2O3 loaded with 10%(mass fraction) MnO2 at the bottom of the reactor.