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
The effect of H_2 gas content on the reduction of Panzhihua titanomagnetite concentrate pellets by carbon monoxide was investigated by isothermal reduction experiment using CO-N_2-H_2 gas mixtures in a vertical electr...The effect of H_2 gas content on the reduction of Panzhihua titanomagnetite concentrate pellets by carbon monoxide was investigated by isothermal reduction experiment using CO-N_2-H_2 gas mixtures in a vertical electric resistance furnace.The morphology and phase transformation of reduced samples obtained were detected by scanning electron microscopy,energy disperse spectroscopy analysis and X-ray diffractometry respectively.The results show that increasing H_2 content will enhance the initial stage of reduction rate apparently.There are two reasons responsible for this effect,one is that H_2 accelerates the chemical reaction,and the other is that the addition of H_2 gas can improve the porosity of pellet intensively.It is noteworthy that this effect is more obvious when the reduction temperature reaches 1473 K with sticking phenomenon happening.There are no crystalline phases which can be found such as ulvospinle,ilmenite,ferrous-pseudobrookite and any titanium oxide except titanomagnetite(TTM).The reduction progress is suggested as follows:1) Fe_2O_3→Fe_3O_4→FeO→Fe;2) Fe_2TiO_5→Fe_2TiO_4+Fe_3O_4→TTM.Element Al migrates and gets enriched in high titanium content iron ores,and eventually Al to Ti molar ratio is 1:3.Al is likely to dissolve in titanium iron oxides to form a kind of composite iron compound,which results in the restrain of reduction.展开更多
分析高炉喷吹焦炉煤气对炉内热量分布及冶炼参数的影响,结果表明高炉喷吹焦炉煤气有助于改善炉内间接还原,从而降低直接还原度、焦比和燃料比,在满足约束条件的前提下每喷吹1 m 3焦炉煤气可减少燃料约0.4 kg。焦炉煤气喷吹造成理论燃烧...分析高炉喷吹焦炉煤气对炉内热量分布及冶炼参数的影响,结果表明高炉喷吹焦炉煤气有助于改善炉内间接还原,从而降低直接还原度、焦比和燃料比,在满足约束条件的前提下每喷吹1 m 3焦炉煤气可减少燃料约0.4 kg。焦炉煤气喷吹造成理论燃烧温度下降,高炉下部热损失增加,高炉上部热损失逐步减小,高炉富氢量对炉内热量分配的影响应成为研究重点。在不富氧条件下,平均每喷吹10 m 3焦炉煤气,理论燃烧温度降低约9.5℃。展开更多
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.
基金Project (51134008) supported by the National Natural Science Foundation of ChinaProject (2012CB720401) supported by the National Basic Research Program of China
文摘The effect of H_2 gas content on the reduction of Panzhihua titanomagnetite concentrate pellets by carbon monoxide was investigated by isothermal reduction experiment using CO-N_2-H_2 gas mixtures in a vertical electric resistance furnace.The morphology and phase transformation of reduced samples obtained were detected by scanning electron microscopy,energy disperse spectroscopy analysis and X-ray diffractometry respectively.The results show that increasing H_2 content will enhance the initial stage of reduction rate apparently.There are two reasons responsible for this effect,one is that H_2 accelerates the chemical reaction,and the other is that the addition of H_2 gas can improve the porosity of pellet intensively.It is noteworthy that this effect is more obvious when the reduction temperature reaches 1473 K with sticking phenomenon happening.There are no crystalline phases which can be found such as ulvospinle,ilmenite,ferrous-pseudobrookite and any titanium oxide except titanomagnetite(TTM).The reduction progress is suggested as follows:1) Fe_2O_3→Fe_3O_4→FeO→Fe;2) Fe_2TiO_5→Fe_2TiO_4+Fe_3O_4→TTM.Element Al migrates and gets enriched in high titanium content iron ores,and eventually Al to Ti molar ratio is 1:3.Al is likely to dissolve in titanium iron oxides to form a kind of composite iron compound,which results in the restrain of reduction.
文摘分析高炉喷吹焦炉煤气对炉内热量分布及冶炼参数的影响,结果表明高炉喷吹焦炉煤气有助于改善炉内间接还原,从而降低直接还原度、焦比和燃料比,在满足约束条件的前提下每喷吹1 m 3焦炉煤气可减少燃料约0.4 kg。焦炉煤气喷吹造成理论燃烧温度下降,高炉下部热损失增加,高炉上部热损失逐步减小,高炉富氢量对炉内热量分配的影响应成为研究重点。在不富氧条件下,平均每喷吹10 m 3焦炉煤气,理论燃烧温度降低约9.5℃。
