As a result of shortage supply of oil resources, the process for the alternative coal-based fuel, dimethyl ether （DME）, has emerged as an important process in chemical engineering field. With the laboratory experime...As a result of shortage supply of oil resources, the process for the alternative coal-based fuel, dimethyl ether （DME）, has emerged as an important process in chemical engineering field. With the laboratory experiment data about DME synthesis and separation, the production process for DME with high purity is proposed when one-step synthesis of DME in slurry bed reactor from syngas is adopted. On the basis of experimental research and process analysis, the proper unit modules and thermophysical calculation methods for the simulation process are selected. Incorporated the experimentally determined parameters of reaction dynamic model for DME synthesis, regression constants of parameters in non-random two-liquid equation （NRTL） model for binary component in DME separation system with built-in properties model, .the process flowsheet, is.developed and simulated on the Aspen Plus platform. The simulation results coincide well with data obtained in laboratory experiment. Accordingly, the accurate simulation results offer useful references to similar equipment design and process operation optimization.展开更多
Mathematical simulation was performed on tube-shell reactor for dimethyl ether （DME） synthesis from coal-based syngas. The model was established based on kinetics of dimethyl-ether synthesis from syngas over a bifun...Mathematical simulation was performed on tube-shell reactor for dimethyl ether （DME） synthesis from coal-based syngas. The model was established based on kinetics of dimethyl-ether synthesis from syngas over a bifunctional catalyst, which is mixed by methanol synthesis catalyst and dehydration catalyst as 1：1 mass ratio. Methanol synthesis from CO and CO2 and methanol dehydration were selected as three-independent reactions, CO, CO2, and DME as key components to estab- lish the one-dimensional mathematical model of the reactor. The gas concentration and temperature profiles inside the reactor tubes were obtained. The operating conditions affecting DME synthesis were also discussed based on the model. The simula- tions indicate that higher pressure and lower temperature at the inlet and rich hydrogen in the reactant are favorable in direct DME synthesis in fixed-bed process, and the temperature of boiling water affect the reactor performance seriously.展开更多
With life cycle assessment(LCA) methodology,a life cycle model of coal-based vehicle fuels(CBVFs) including coal-based dimethyl ether(CBDME) and coal-based diesel(CBD) is established.Their primary energy consumption(P...With life cycle assessment(LCA) methodology,a life cycle model of coal-based vehicle fuels(CBVFs) including coal-based dimethyl ether(CBDME) and coal-based diesel(CBD) is established.Their primary energy consumption(PEC) and global warming potential(GWP) from well to wheel including feedstock extraction,fuel production,fuel consumption in vehicle and energy transportation are calculated and compared.Results show that the life cycle PEC and GWP of CBD pathway are 1.17 and 1.34 times as CBDME pathway.Based on the above results,CBDME will become a choice with great potential to replace conventional petroleum-based diesel (CPBD) in China.展开更多
基金Supported by the National Technology Support Program of China(2006BAE02B02)the National Basic Research Program of China (2005CB221205)
文摘As a result of shortage supply of oil resources, the process for the alternative coal-based fuel, dimethyl ether （DME）, has emerged as an important process in chemical engineering field. With the laboratory experiment data about DME synthesis and separation, the production process for DME with high purity is proposed when one-step synthesis of DME in slurry bed reactor from syngas is adopted. On the basis of experimental research and process analysis, the proper unit modules and thermophysical calculation methods for the simulation process are selected. Incorporated the experimentally determined parameters of reaction dynamic model for DME synthesis, regression constants of parameters in non-random two-liquid equation （NRTL） model for binary component in DME separation system with built-in properties model, .the process flowsheet, is.developed and simulated on the Aspen Plus platform. The simulation results coincide well with data obtained in laboratory experiment. Accordingly, the accurate simulation results offer useful references to similar equipment design and process operation optimization.
文摘Mathematical simulation was performed on tube-shell reactor for dimethyl ether （DME） synthesis from coal-based syngas. The model was established based on kinetics of dimethyl-ether synthesis from syngas over a bifunctional catalyst, which is mixed by methanol synthesis catalyst and dehydration catalyst as 1：1 mass ratio. Methanol synthesis from CO and CO2 and methanol dehydration were selected as three-independent reactions, CO, CO2, and DME as key components to estab- lish the one-dimensional mathematical model of the reactor. The gas concentration and temperature profiles inside the reactor tubes were obtained. The operating conditions affecting DME synthesis were also discussed based on the model. The simula- tions indicate that higher pressure and lower temperature at the inlet and rich hydrogen in the reactant are favorable in direct DME synthesis in fixed-bed process, and the temperature of boiling water affect the reactor performance seriously.
文摘With life cycle assessment(LCA) methodology,a life cycle model of coal-based vehicle fuels(CBVFs) including coal-based dimethyl ether(CBDME) and coal-based diesel(CBD) is established.Their primary energy consumption(PEC) and global warming potential(GWP) from well to wheel including feedstock extraction,fuel production,fuel consumption in vehicle and energy transportation are calculated and compared.Results show that the life cycle PEC and GWP of CBD pathway are 1.17 and 1.34 times as CBDME pathway.Based on the above results,CBDME will become a choice with great potential to replace conventional petroleum-based diesel (CPBD) in China.
