关键词: 乏风瓦斯, 热逆流氧化, 数值模拟

Abstract: In this paper, an one-dimensional mathematical mode was set up, to investigate the thermal reverse-flow oxidation of ventilation air methane (VAM) in coal mine, and Fluent software was adopted to simulate the effects of the thermal structures of oxidation bed and the operating condition parameters on the thermal structure, oxidation ratio of methane and outlet temperature. The results indicate that: 1) The temperature field of oxidation bed presents trapezium distribution, and the high-temperature zone makes reciprocating movement periodically along the height direction of oxidation bed. 2) With the increase of methane concentration, the high-temperature zone widens, and the maximum temperature and the outlet temperature increase accordingly, while the oxidation ratio of methane increases slightly. 3) As the ventilation air volume increases, the peak temperature, reaction rate and outlet temperature all rise significantly, the reaction zone moves towards both ends of the oxidation bed, and the high-temperature zone widens, while the oxidation ratio of methane decreases. 4) With the extension of half cycle, the reaction zone and high-temperature zone move towards the center of oxidation bed, the
high-temperature zone narrows down, the outlet temperature increases, and the oxidation ratio of methane decreases slightly. 5) With the continuous increase of heat loss on wall, the peak temperature, the temperature in high-temperature zone, and the oxidation ratio of methane gas all decrease, the reaction rate also falls sharply, while the high-temperature zone narrows down distinctly.

Key words: ventilation air methane (VAM), thermal reverse-flow oxidation, numerical simulation