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A three-dimensional geometric model was set up for the oxidative coupling of methane(OCM) fixed bed reactor loaded with Na_3PO_4-Mn/SiO_2/cordierite monolithic catalyst,and an improved Stansch kinetic model was established to calculate the OCM reactions using the computational fluid dynamics method and Fluent software.The simulation conditions were completely the same with the experimental conditions that the volume velocity of the reactant is 80 ml·min~(-1) under standard state,the CH_4/O_2 ratio is 3 and the temperature and pressure is800 ℃ and 1 atm,respectively.The contour of the characteristic parameters in the catalyst bed was analyzed,such as the species mass fractions,temperature,the heat flux on side wall surface,pressure,fluid density and velocity.The results showed that the calculated values matched well with the experimental values on the conversion of CH4 and the selectivity of products(C_2H_6,C_2H_4,CO,CO_2 and H_2) in the reactor outlet with an error range of±4%.The mass fractions of CH_4 and O_2 decreased from 0.600 and 0.400 at the catalyst bed inlet to 0.445 and0.120 at the outlet,where the mass fractions of C_2H_6,C_2H_4,CO and CO_2 were 0.0245,0.0460,0.0537 and 0.116,respectively.Due to the existence of laminar boundary layer,the mass fraction contours of each species bent upwards in the vicinity of the boundary layer.The volume of OCM reaction was changing with the proceeding of reaction,and the total moles of products were greater than reactants.The flow field in the catalyst bed maintained constant temperature and pressure.The fluid density decreased gradually from 2.28 kg·m~(-3) at the inlet of the catalyst bed to 2.18 kg·m~(-3) at the outlet of the catalyst bed,while the average velocity magnitude increased from 0.108 m·s-1 to 0.120 m·s~(-1).
A three-dimensional geometric model was set up for the oxidative coupling of methane (OCM) fixed bed reactor loaded with Na_3PO_4-Mn / SiO_2 / cordierite monolithic catalyst, and an improved Stansch kinetic model was established to calculate the OCM reactions using the computational fluid dynamics method and Fluent software. The simulation conditions were completely the same with the experimental conditions that the volume velocity of the reactant is 80 ml · min -1 under standard state, the CH_4 / O_2 ratio is 3 and the temperature and pressure is800 ℃ and 1 atm, respectively. The contour of the characteristic parameters in the catalyst bed was analyzed, such as the species mass fractions, temperature, the heat flux on side wall surface, pressure, fluid density and velocity. The results showed that the calculated values matched well with the experimental values on the conversion of CH4 and the selectivity of products (C_2H_6, C_2H_4, CO, CO_2 and H_2) in the reactor outlet with an error range of ± 4%. mass fractions of CH 4 and O 2 decreased from 0.600 and 0.400 at the catalyst bed inlet to 0.445 and 0.120 at the outlet, where the mass fractions of C 2 H 6, C 2 H 4, CO and CO 2 were 0.0245, 0.0460, 0.0537 and 0.116, respectively. D to the existence of laminar boundary layer, the mass fraction contours of each species bent upwards in the vicinity of the boundary layer. volume of OCM reaction was changing with the proceeding of reaction, and the total moles of products were greater than reactants. flow field in the catalyst bed maintained constant temperature and pressure.The fluid density gradually gradually from 2.28 kg · m -3 at the inlet of the catalyst bed to 2.18 kg · m -3 at the outlet of the catalyst bed , while the average velocity magnitude increased from 0.108 m · s-1 to 0.120 m · s -1.