| Pyrolysis of coal in an electric arc plasma to produce organic,, matters (main for acetylene) is an important subject with respect to using coal efficiently, clearly and deeply, the scientists all over the world proceed to this study one after another since the 60's of twenty's centuries. Because this process has the latent industry application foreground, with consideration to the fact of our country's lack of oil but rich in coal, producing acetylene from coal (as the main raw material) has important strategy meaning to our country and even to the world. State Key Laboratory of Cl Chemistry and Technology in Taiyuan University Of Technology and thermal energy department of Tsinghua University cooperate to proceed this subject efficiently as a key subsidizing item of national natural science fund, its breakthrough will changing the situation of coal using as resource.Based on the pyrolysis experiments of different coal under arcplasma jet, this text mainly investigate the effect of several process factors on the pyrolysis results, these factors include acetylene yield, gaseous gross yield( conversion rate), acetylene selectivity in hydrocarbons, competition of acetylene and carbon monoxide , Specific energy consume of acetylene. Several coals having higher conversion and acetylene yield been selected to do experiment further, the concentrations of gaseous products along reactor beendetermined, the best position of quenching been picked, theinfluence of specific coal enthalpy and quenching on the acetylene yield and the selectivity are investigated respectively. Then the experiment had been further done through the changing of operation conditions (power, atmosphere), the improving of the reactor structure and thermal efficiency. The rules of gaseous products of coal pyrolysis under electric arc plasma and main influencing factors been summarized, the fact that the quality and quantity of coal's volatiles affect not only acetylene yield but also the process of coking is been pointed out. Not only the carbon in low molecular hydrocarbon but also aromatic carbons participated the reactions of producing acetylene. The reactions of acetylene compete with those of carbon monoxide, the quenching and improvement of hydrogen fraction in the plasma atmosphere benefit to the acetylene yield. Thermal efficiency of the Process is key tototal system, but the process of heat transferred to the coal particlesis a control step for the mechanism of coal pyrolysis in arc plasma for acetylene, this step is influenced by the operational conditions, therefore improve the reactor structure and heat efficiency can increase acetylene yield and decrease cokes on the reactor wall. Considering the composition of volatiles, several model compounds were selected and studied, it discovered that both the carbon in low molecular hydrocarbons and the aromatic carbons participated the formation of acetylene and coking, but their functions are differently.In order to increase acetylene yield, it is ultimately important to select the suit coal, it is primarily important to keep the reaction system on the high levels of temperature and Specific Coal Enthalpy, it is key to have hydrogenous active species participate the process. Decrease and conversion of coke ensured the continuity of the process. Coagulate of aromatics is a very important path to forming soot in pyrolysis of coal under plasma torch. The active species, which produced by pyrolysis of coal under plasma, react each other. When the polymerization rate of coke precursors in the gas was high enough, the molecular became large and could not stayed in the gas, thus forming the soot, when the rate was low the molecular had enough time to diffuse toward the reactor wall,thus foming the coke. Whether to form soot brought out system or coke deposited on the reactor wall is a actual problem of control theappearance and character of solid products. If operation conditions are controlled or reactor structure improved so that greatly decrease carbons depos...
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