Based on thermodynamics and physical chemistry theory,the theoretical energy consumption (TEC) of the typical separating processes of Al,Ca and Mg has been calculated and analyzed.This paper attempts to prove that the...Based on thermodynamics and physical chemistry theory,the theoretical energy consumption (TEC) of the typical separating processes of Al,Ca and Mg has been calculated and analyzed.This paper attempts to prove that the thermal method is more reasonable than the electrolytic methods to separate Al,Ca and Mg under the domestic circumstances of the low efficiency of coal-firing power plant at present.展开更多
The theoretical energy consumption(TEC)analytical methods and the calculated models for the electrolytic and thermal reduction metal separation processes have been put forward based on thermodynamics and physical chem...The theoretical energy consumption(TEC)analytical methods and the calculated models for the electrolytic and thermal reduction metal separation processes have been put forward based on thermodynamics and physical chemistry principles,providing theoretical foundation for choosing the optimum metal separation methods.Based on the models,the TECs of the Mg separation processes are taken as an example,and have been calculated and analyzed contrastively,including the MgCl_2 electrolytic method,the MgO electrolytic method with inert electrode and with carbon anode,and the silicothermic method.It is shown that the thermal method is more reasonable than the electrolytic methods to separate Mg under low efficiency of coal power generation.展开更多
Theoretical minimum and actual specific energy consumptions （SEC） of typical manufacturing process （SMP） were studied. Firstly, a process division of a typical SMP in question was conducted with the theory of SEC ...Theoretical minimum and actual specific energy consumptions （SEC） of typical manufacturing process （SMP） were studied. Firstly, a process division of a typical SMP in question was conducted with the theory of SEC analysis. Secondly, an exergy analysis model of a subsystem consisting of several parallel processes and a SEC analysis model of SMP were developed. And finally, based on the analysis models, the SEC of SMP was analyzed by means of the statistical significance. The results show that the SEC of typical SMP comprises the theoretical minimum SEC and the additional SEC derived from the irreversibility~ and the SMP has a theoretical minimum SEC of 6.74 GJ/t and an additional SEC of 19.32 GJ/t, which account for 25.88% and 74.12% of the actual SEC, respectively.展开更多
Based on the stoichiometric method and the free energy minimization method,an ideal model for the reduction of iron oxides by carbon and hydrogen under blast furnace conditions was established,and the reduction effici...Based on the stoichiometric method and the free energy minimization method,an ideal model for the reduction of iron oxides by carbon and hydrogen under blast furnace conditions was established,and the reduction efficiency and theoretical energy consumption of the all-carbon blast furnace and the hydrogen-rich blast furnace were compared.The results show that after the reduction reaction is completed at the bottom of the blast furnace,the gas produced by reduction at 1600℃still has a certain excessive reduction capacity,which is due to the hydrogen brought in by the hydrogen-rich blast as well as the excess carbon monoxide generated by the reaction of the coke and the oxygen brought in by the blast.During the process of the gas with excessive reduction capacity rising from the bottom of the blast furnace and gas reduction process,the excessive reduction capacity of the gas gradually decreases with the increase in the dydrogen content in the blast.In the all-carbon blast furnace,the excess gas reduction capacity is the strongest,and the total energy consumption per ton of iron reduction is the lowest.This shows that,for the current operation mode of the blast furnace,adding hydrogen in the blast furnace cannot reduce the consumption of carbon required for reduction per ton of iron,but rather increases the consumption of carbon.展开更多
文摘Based on thermodynamics and physical chemistry theory,the theoretical energy consumption (TEC) of the typical separating processes of Al,Ca and Mg has been calculated and analyzed.This paper attempts to prove that the thermal method is more reasonable than the electrolytic methods to separate Al,Ca and Mg under the domestic circumstances of the low efficiency of coal-firing power plant at present.
文摘The theoretical energy consumption(TEC)analytical methods and the calculated models for the electrolytic and thermal reduction metal separation processes have been put forward based on thermodynamics and physical chemistry principles,providing theoretical foundation for choosing the optimum metal separation methods.Based on the models,the TECs of the Mg separation processes are taken as an example,and have been calculated and analyzed contrastively,including the MgCl_2 electrolytic method,the MgO electrolytic method with inert electrode and with carbon anode,and the silicothermic method.It is shown that the thermal method is more reasonable than the electrolytic methods to separate Mg under low efficiency of coal power generation.
基金Item Sponsored by Fundamental Research Funds for the Central Universities of China(N090602007)National Key Technology Research and Development Program in 11th Five-Year Plan Project of China(2006BAE03A09)
文摘Theoretical minimum and actual specific energy consumptions （SEC） of typical manufacturing process （SMP） were studied. Firstly, a process division of a typical SMP in question was conducted with the theory of SEC analysis. Secondly, an exergy analysis model of a subsystem consisting of several parallel processes and a SEC analysis model of SMP were developed. And finally, based on the analysis models, the SEC of SMP was analyzed by means of the statistical significance. The results show that the SEC of typical SMP comprises the theoretical minimum SEC and the additional SEC derived from the irreversibility~ and the SMP has a theoretical minimum SEC of 6.74 GJ/t and an additional SEC of 19.32 GJ/t, which account for 25.88% and 74.12% of the actual SEC, respectively.
基金The author are thankful for the support from the National Natural Science Foundation of China(Nos.U1560203,51704021,and 51274031)Beijing Key Laboratory of Special Melting and Preparation of High-End Metal Materials.
文摘Based on the stoichiometric method and the free energy minimization method,an ideal model for the reduction of iron oxides by carbon and hydrogen under blast furnace conditions was established,and the reduction efficiency and theoretical energy consumption of the all-carbon blast furnace and the hydrogen-rich blast furnace were compared.The results show that after the reduction reaction is completed at the bottom of the blast furnace,the gas produced by reduction at 1600℃still has a certain excessive reduction capacity,which is due to the hydrogen brought in by the hydrogen-rich blast as well as the excess carbon monoxide generated by the reaction of the coke and the oxygen brought in by the blast.During the process of the gas with excessive reduction capacity rising from the bottom of the blast furnace and gas reduction process,the excessive reduction capacity of the gas gradually decreases with the increase in the dydrogen content in the blast.In the all-carbon blast furnace,the excess gas reduction capacity is the strongest,and the total energy consumption per ton of iron reduction is the lowest.This shows that,for the current operation mode of the blast furnace,adding hydrogen in the blast furnace cannot reduce the consumption of carbon required for reduction per ton of iron,but rather increases the consumption of carbon.
