Abstract: The effects of reaction temperature and pressure on the equilibrium of CO₂ and CO methanation reaction systems were studied during the methanation process of high-temperature coal gasification, and the reactant conversion rate, CH₄ yield, and reaction were obtained.The equilibrium constant and the dynamics of the dynamic equation.Studies have shown that: within 900-1 200 ℃,the conversion rate of CO and CO₂ and the yield of CH₄ during their methanation alone decrease with increasing temperature and increase with increasing pressure.When the reaction conditions was that the pressure is 0.1 MPa and temperature is 900 ℃,the theoretical conversion rates of CO and CO₂ in separate methanation reactions were 5.107% and 7.738%,the yield of CH₄ were 9.741% and 7.099%,respectively.When the volume ratio of H₂,CO and CO₂ is 7∶1∶1,the theoretical conversion of CO₂ and CO in CO and CO₂ mixed methanation reactions.The rates were 81.062% and-80.620%,respectively, the yield of CH₄ were 5.432%.When the reaction temperature rises to 1 200 ℃ and the pressure is 0.1 MPa, the theoretical conversion rates of methanized CO and CO₂ alone were 0.449% and 0.390%,the yield of CH₄ were 0.170% and 0.597%,respectively.The theoretical conversions of CO₂ and CO were 88.791% and-88.791%,respectively, and the yield of CH₄ were 0.205%.Finally, the kinetic equation expression of CO₂ and CO methanation in the temperature range of 900-1 200 ℃ was obtained through calculated.The rationality of the kinetic equation was analyzed and verified by Aspen Plus.