| It is well known that methane is the second largest contributor to global warming after carbon dioxide, and it is21times more potent than carbon dioxide over a100-year timeframe in trapping heat in the atmosphere. The vetilation air methane (VAM) of coal mine is one of the primary industrial methane emission sources. The reduction of VAM will make outstanding contributions for reducing emissions that cause of global warming. Meanwhile, the main components of ventilation gas are methane, which is the high quality undefiled gas energy. According to the statistics, the gas emission to the atmosphere through ventilation air methane is about20billion m3, which is corresponding to25miliiion tons standard coal that can reduce emission270million tons equivalent carbon dioxide. Therefore; recovery and utilization of VAM has great environment protection and energy-saving significance.VAM is the most difficult source of methane to use as an energy source, as the air volume is large and the methane resource is dilute. At present, the thermal flow-reversal reactor is an effectively technology that realize recovery and utilization of VAM. Through theoretical analysis, numerical simulation and experiment, we made comprehensive research on the oxidation mechanism and characteristics of thermal reverse-flow oxidation of VAM:(l)The two relations about combustion wave and the highest combustion area temperature have been established that got the closed solution of combustion wave and combustion area. The simple theoretical solution about porous media thermal flow-reversal oxidation was also obtained.(2)The resistance mathematical model have been established in the cold and hot state of three honeycomb ceramics oxidation bed that influence by VAM intake velocity, honeycomb ceramics channel diameter (side length), gas viscosity and the temperature fields of oxidation bed that through theoretical analysis about the flowing process of the honeycomb ceramics thermal storage oxidation bed.(3)Based on secondary development on FLUENT, a one-dimensional mathematical mode was set up to simulate the thermal structures of the oxidation bed and the effect of operating condition parameters on the thermal structure, oxidation ratio of methane and outlet temperature, which includes flow velocity, methane concentration, half-period, thermal loss, honeycomb ceramics specific heat capacity and porosity.(4)According to the experiment system of VAM thermal flow-reversal oxidation made by self-designed; the comprehensive study to the VAM thermal flow-reversal oxidation hase been developed, which contains heat loss, temperature fields of hot-start, methane concentration, ventilation gas and honeycomb ceramics porosity.(5)Hexa-aluminate as coatings coat the surface of γ-alumina and load active components of noble metal have been used to make the honeycomb ceramics integral catalyst and use it in the VAM low concentration gas thermal flow-reversal oxidation and through single pipe fixed bed catalytic oxidation experiment testing the preparation catalyst about characterization, activity evaluation, thermal stability and sulfur poisoning ability.(6)Through the experiment of thermal flow-reversal catalytic oxidation of VAM, comparing with thermal flow-reversal without catalyst, it concluded that not only did the catalyst decrease the oxidation temperature of VAM, but also the conversation rate of catalyst enhanced obviously, at the same time, the catalyst improve the device's treatment capacity.(7)Taken the single station device treating50000m3/h VAM as research object, calculated the carbon emission reduction which produced by destroying methane with single station device per year and the quantity of hot water and steam, which were produced by the utilized heat, meanwhile, the CMD income and energy using income of single station device per year were evaluated, also, the rate of return was analyzed.
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