Catalytic combustion of CH4/air in monolith reactor is simulated using a commercial computational fluid dy-namic code. The user subroutines to describe the heterogeneous reaction at the channel wall in a single channe...Catalytic combustion of CH4/air in monolith reactor is simulated using a commercial computational fluid dy-namic code. The user subroutines to describe the heterogeneous reaction at the channel wall in a single channel and at the channel walls in the whole reactor are incorporated into the program. The correctness of the method is verified by com-paring the simulation results with the experimental data for the whole reactor. Furthermore, it is observed that the model based on the whole reactor is more reasonable than that based on a single channel. Therefore, using the former, the effects of operating conditions such as inlet gas velocity, temperature, concentration and catalyst loading on methane conversion are investigated.展开更多
This work is focused on the performance prediction of pilot scale catalytic reverse flow reactors used for combustion of lean methane-air mixtures. An unsteady one-dimensional heterogeneous model for the reactor was e...This work is focused on the performance prediction of pilot scale catalytic reverse flow reactors used for combustion of lean methane-air mixtures. An unsteady one-dimensional heterogeneous model for the reactor was established to account for the influence of the reactor wall on the heat transfer. Results of the simulation indicate that feed concentration, switch time and compensatory temperature impose important influence on the performance of the reactor. The amount of the heat extracted from the mid-section of the reactor can be optimized via adjusting the parameters mentioned above. At the optimal operating conditions, Le. switching time of 400 s, feed concentration of 1% （by volume）, and insulation layer temperature of 343 K, the axial temperature of the reactor revealed a comparatively symmetrical ＂saddle＂ distribution, indicating a favorable operating status of the catalytic reverse flow reactor.展开更多
A steady-state ID macro-homogeneous model is developed to illustrate the combustion process of methane with ozone in the reactor composed of Pd-exchanged zeolite X. The model is validated by comparing the predicted re...A steady-state ID macro-homogeneous model is developed to illustrate the combustion process of methane with ozone in the reactor composed of Pd-exchanged zeolite X. The model is validated by comparing the predicted results with the measured data. The methane conversion increases with decreasing the inlet methane concentration and gas space velocity and increasing the inlet ozone concentration and temperature. As the reactor length reduces, the methane conversion varies little if the reactor is too long but decreases when the reactor is too short. Therefore, the reactor should he properly designed to balance costs and the methane-conversion efficiency.展开更多
基金Supported by the National Natural Science Foundation of China (No.20136010 and No.20376005).
文摘Catalytic combustion of CH4/air in monolith reactor is simulated using a commercial computational fluid dy-namic code. The user subroutines to describe the heterogeneous reaction at the channel wall in a single channel and at the channel walls in the whole reactor are incorporated into the program. The correctness of the method is verified by com-paring the simulation results with the experimental data for the whole reactor. Furthermore, it is observed that the model based on the whole reactor is more reasonable than that based on a single channel. Therefore, using the former, the effects of operating conditions such as inlet gas velocity, temperature, concentration and catalyst loading on methane conversion are investigated.
基金Supported by the National High Technology Research and Development Program of China(2006AA030201)
文摘This work is focused on the performance prediction of pilot scale catalytic reverse flow reactors used for combustion of lean methane-air mixtures. An unsteady one-dimensional heterogeneous model for the reactor was established to account for the influence of the reactor wall on the heat transfer. Results of the simulation indicate that feed concentration, switch time and compensatory temperature impose important influence on the performance of the reactor. The amount of the heat extracted from the mid-section of the reactor can be optimized via adjusting the parameters mentioned above. At the optimal operating conditions, Le. switching time of 400 s, feed concentration of 1% （by volume）, and insulation layer temperature of 343 K, the axial temperature of the reactor revealed a comparatively symmetrical ＂saddle＂ distribution, indicating a favorable operating status of the catalytic reverse flow reactor.
基金supported by the Natural Science Foundation for Distinguished Young Scholars of Chongqing(CSTC2012JJJQ90003)the National Natural Science Foundation of China(51222603,51325602,51276208)+2 种基金the Fundamental Research Funds for the Central Universities(CDJZR12148801)the Program for New Century Excellent Talents in University(NCET120591)the RGC General Research Fund of HKSAR(City U114310)
文摘A steady-state ID macro-homogeneous model is developed to illustrate the combustion process of methane with ozone in the reactor composed of Pd-exchanged zeolite X. The model is validated by comparing the predicted results with the measured data. The methane conversion increases with decreasing the inlet methane concentration and gas space velocity and increasing the inlet ozone concentration and temperature. As the reactor length reduces, the methane conversion varies little if the reactor is too long but decreases when the reactor is too short. Therefore, the reactor should he properly designed to balance costs and the methane-conversion efficiency.
