Experimental Study On Photocatalytic Oxidation Coupled With Bio-Trickling To Purify Malodorous Gases

The problem of odorous gas pollution in the living environment endangering human health has become increasingly prominent,and effective purification of malodorous gas has become one of the environmental problems to be solved urgently.The composition of pollutants in malodorous gases is complex,and a single purification method is often difficult to achieve the desired effect.Therefore,high-concentration,multi-component malodorous gases are combined with existing malodorous exhaust gas treatment technologies to develop efficient,economical and environmentally friendly New purification technology has become a hot issue in the field of air pollution prevention research.The test results show that:Photocatalytic oxidation process conditions,the selection of 185-254 nm double wavelength uv lamp as light source,homemade Fe3+/TiO2 catalyst to the stench gas purification effect is better than the standard commercial TiO2 catalyst,when the concentration of NH3 intake is 208-584 mg/m3,concentration of H2S gas inlet is 196-578 mg/m3,C2H5SH inlet cocentration of 5.2 to 40.1 mg/m3,the odour removal rate and decreased with inlet concentration increase,the stench gas residence time of 0.8 s to 2.4 s,odour removal rate with the extension of time,When the uv lamp power is 240w-960w,the odor removal rate increases with the increase of the uv lamp power.Under the condition of biotrickling filtration process,the dynamic film-hanging time of biotrickling filter is 25 days by adding glucose as co-metabolic matrix and gas-liquid phase combined membrane-hanging method.In the stable operation stage,the inlet concentration,residence time and gas-liquid ratio of odor gas have significant effects on the removal efficiency of odor.The optimum reaction parameters under the experimental conditions are NH3 inlet concentration 77.93-271.57 mg/m3 and H2S inlet concentration 114.64-423.76mg/m3,intake concentration of C2H5SH 63.7-313.42mg/m3,residence time 5s,gas-liquid ratio 277.8:1,spray pH 6.5-7.5,biotrickling filtration has better recovery performance and can cope with intermittent operation.Photocatalytic oxidation coupled biological filter process conditions,starts to hang membrane biological filter tower than single biological drops craft hang membrane filtration tower started days shorten by a third,Only 11 days,during the test,the coupling process of H2S,NH3,C2H5SH removal rate were 95%,97%and 87%,respectively,in the light catalysis and biological filter in residence time of 2 s and 2.4 s respectively the best operation parameters conditions,when the concentration of NH3 and H2S,C2H5SH intake were as high as 570 mg/m3,568 mg/m3 and 16.5 mg/m3,The removal rate of coupling process still reached 96.6%,97.1%and 88.7%.