Removal Of CS₂ In The Industrial Tail Gas By DC Corona Plasma

In recent years,air pollution has become more and more serious,in which industrial exhaust pollution accounted for a large part of the proportion.Industrial exhaust gas not only contain Carbon disulfide(CS2),Nitrogen oxides(NOx),Hydrogen sulfide(H2S)and Carbonyl sulfide(COS),heavy metals,dust and other pollutants are also exist.CS2 was not only polluting the atmosphere and pose a threat to human health,but corrosion the equipment and impact the lifetime of the catalyst in subsequent production.Dust particle is one of the main culprit of air pollution.It’s not only impact on human health but also harm the machinery and equipment.The existing gas removal processes had removed the dust particles of the gas at first,and removed the different contaminants using the combined process.It’s necessary to research the method which can deal with CS2 and dust at the same time since that the separation process is costly and complicated.Treating the dust and CS2 through DC corona discharge,simulating reaction gas through the devices which configure gas and generate dust.The effect of the electrode type,reactor temperature and humidity,gas inlet concentration,oxygen concentration,gas residence time,discharge gap and dust concentration on the removal of CS2 were studied in the experiment.The mechanisms of removal of dust and CS2 by DC corona discharge were analyzed by product measurement and representation includes FTIR and XRD.The CS2 removal efficiency of jagged and stringed electrodes was far below the round steel electrode since that their curvature radius were too big.The removal efficiency of CS2 increased with the special input energy(SIE).The amount of CS2 removed was equivalent to the sum of COS,CO,and CO2,and the results show that the carbon kept balance in the experiment.In the same SIE,the removal efficiency of CS2 decreased with the increase of inlet concentration.The energy yield(EY)increased with the increase of inlet concentration.A part of SO2 was oxidized to SO3 and SO42-with the increase of the SIE.O2 was an electronegative gas and was ionized to produce oxygen free radicals in the reactor.There was higher the O2 concentration,the higher the O3 production rate was,the energy consumption was more,the removal efficiency of CS2 was lower.O3 had little effect on the removal of CS2.At the same voltage,the higher the reactor temperature was,the activity of particles in the electric field was greater,there was the higher the removal rate of CS2,but the breakdown voltage of reactor was lower.The larger the discharge gap of the reactor was,the lower the removal efficiency of CS2 was.The residence time of the mixture in the reactor was shorter,the energy required to achieve the same CS2 removal efficiency was less.After mixed CS2,H2S and COS into the reactor,in the same energy the concentration of COS was the highest and the concentration of H2S was the lowest at the outlet.In the experiment,corona discharge could simultaneously remove CS2 and dust particles.When the SIE was 60 J/L,the removal rate of CS2 was 70%and the SO2 production rate was 30.6%.After add the dust,the removal rate of CS2 was 75%and the SO2 production rate was 16%.The collected product after the addition of dust was analyzed by XRD.It also contains elemental sulfur and sulfate except for SiO2,CaF2 and AlPO4.It indicate that the sulfur element in CS2 was oxidized to sulfur,SO2 and sulfate in the experiment.Sulfur element maintains a balance.DC corona simultaneous purification of CS2 and dust is feasible and significant.