| The pollution and control techniques of odors are received increasing attention with the industrial developing and the living quality required more and more highly, especially the sulfide odors are with lower odor threshold value and larger toxicity. Pulsed corona(non-thermal plasma) technique is of focus on the treatment of sulfide odors,which has high destruction efficiency,simply installed and widely applicable. In this paper,serial and parallel reactors,activated carbon fibers(ACF) adsorption are used to treat H2S.And we studied to decompose the dimethyl sulfide and ethanethiol in DBD reactor,discussed the byproduces decomposition mechanisms and kinetics. The main conclusions of this work are drawn:1.The peak voltage decreases,pulse rise time becomes slower and pulse width increases at the same of discharge voltage with serial and parallel reactors compared with single reactor.At low discharge voltage(＜9 kV),the impedance ratio decreases from 4.5 to 2.9,and energy yield improves about 10%with serial and parallel modes. H2S removal efficiency reaches nearly 100%at discharge voltage 13 kV and 14 kV with serial modes and parallel modes,respectively,while H2S removal efficiency is only 88%and 91%at the same discharge voltage with single mode.When the removal amounts of H2S is 200 mg/m3,the energy consumption index is 43 J/L,51 J/L,68 J/L with single,parallel and serial modes,respectively.O3 concentration increases at the same of discharge voltage with serial and parallel modes.2.Decomposition of H2S was carried out by the combination of pulse corona and ACF.The addition of ACF improves effectively H2S removal efficiency,the EC value reduces and EY value increases at the same of discharge voltage.Compared to single ACF adsorption,the breakthrough time of ACF for H2S is prolonged the most of 16 times with pulsed corona,the adsorption and decomposition capacity improves 4.2 times for H2S and 1.6 times for O3 at 6 kV,During pulse corona reactor,the byproducts,such as O3,SO2,NOx can be controlled and aren't detected before the breakthrough time of ACF for H2S.3.The H2S removal efficiency is up to 88%,and improves 15%at 6 kV in synergetic system of pulse corona and ACF adsorption compared with single pulsed corona,which is equivalent with single pulse corona at 7 kV.The EC value reduces 21 eV/molecules and EY value increases 1.7 mg/kJ,the energy consumptionm at 6 kV reduces 26.5%. 4.The removal efficiencies of CH3SCH and C2H5SH increase with the pulsed frequency and peak voltage increasing in DBD reactor,and can reach 100%at appropriate conditions.But the energy yields are the most and achieve 0.338 mg/kJ, 0.223 mg/kJ at 100 pps,respectively.When the initial concentrations and flow rate increase,the removal efficiencies of CH3SCH and C2H5SH decrease at the same peak voltage.However,the absolute removal amounts and energy yield rise.The gas humidity has great effect on the CH3SCH3 removal efficiency;furthermore the removal efficiency improves effectively with the humidity increasing.The CH3SCH3 achives to remove completely and EY gets 2.87 mg/kJ at the critical corona voltage when the gas humidity exceeds 30%.When the O2 content is 5%,the CH3SCH3 removal efficiency reaches the most and the energy yield is the most of 0.295 mg/kJ at the same voltage.The energy yield reduces when the O2 content both increases and decreases.5.The O3,NOx,concentration decrease and SO2 concentration increases with CH3SCH3 initial concentration increasing,but the SO2 selectivity(SB) slows down. The gas humidity is 6%and 14%,which promotes the production of O3 and has little effect on NOx.The SO2 concentration improves with initial concentration increasing, but SO2 selectivity becomes lower.At the same peak voltage,O2 content improves the production of SO2,the SO2 selectivity increases because the S element is oxidized relatively completely.6.By means of products analysis,the decomposition mechanisms of CH3SCH3 and C2H5SH are considered that the free radical reaction is major intermediate process. Through the kinetics model fitting of CH3SCH3 decomposition,it is considered that CH3SCH3 decomposition conforms to no significant radical terminations model.
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