| Industrial malodors pollution is receiving more and more concern and attention.Traditional malodors control methods are limited technically and economically,especially for high volume low concentration malodors emissions. DC corona radicalshower technique is regarded as a promising technique for malodors control, whichcan greatly reduce the complexity of operating and investment costs of stenchremoval.Firstly, in this dissertation, the applied study of simulated actual refinerymalodors was investigated systelnatically. Based on this, the plasma-absorption jointtreatment malodors pilot plant was designed. The maximum output voltage of DCpower supply was 60 kV, and total gas-flow rates of the experiment were between0.06 and 10 m3·h-1. The goals of the experiments were to conduct the large-scaleindustrial application design and supply the experimental datas and theoretical basisfor process control.The conclusion shows:1) Experiments of the removal of hydrogen sulfide, the representativemalodorant of refinery industry, by direct current corona plasma were investigated.Dynamic and static deodorizing experiments in an oxidative atmosphere and the staticremoval of hydrogen sulfide in a reductive atmosphere were studied. Operationalparameters, such as peak voltage, applied power, residence time, initial concentration,gas temperature, humidity and oxidative and reductive atmosphere, were discussed.The results showed that increasing the peak voltage and residence time can improvethe removal efficiency; increasing the concentration and tempreture of waste gas willweaken the removal efficiency; when humidity reached beyond RH=56%, removalefficiency would be decreased; the most important factor in the removal process is theoxygen content. Only 40.87% of hydrogen sulfide was removed in the reductiveatmosphere with hydrogen and nitrogen. When 10% volume fraction oxygen wasadded in the reductive atmosphere, the removal efficiency considerably increased to80%. In the oxidative atmosphere with nitrogen, hydrogen and 10%-20% volumefraction oxygen, sulfide could be decomposed completely with increasing time. Theincrease of the oxygen content can improve the removal efficiency of hydrogen sulfide.2) Based on the previous experiments, a large-scale plasma reactor was designed,which could produce waste gas between 1,000 m3 h-1 and 2,500 m3 h-1. Theplasma-absorption joint industrial odor control technology was discussed, thesieve-plate column and packed tower were calculated and the sieve-platecolumn-packing tower-plasma reactor three small pilot plant were schemed. Thesieve-plate column can absorb malodors so effective that it can be used as apretreatment for plasma reactor.3) The validity and economic quality of the thchnology were analyzedpreliminary. The energy consumption of plasma reactor, which can deal with gas-flowrate between 1000～2500 m3·h-1, is calculated corresponding the method of linearextrapolation. The technical and economic index of the DC corona plasma reactor,pulsed corona plasma reactor and catalytic combustion was compared elementarily,which proved a highly technical superiority of DC plasma technology.4) The by-products were analysed under diferent conditions(oxidative andreductive atmosphere). Based on the product and literature analyse, the decompositionmechanisms of H2S were discussed.A dynamics model was proposed to describe the relation of the removalefficiency with energy density, and initial concentration. The decomposition rateconstants of H2S were 0.0781 J·m-3.
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