A high-temperature reduction roasting method was used to achieve metallic iron and zinc recovery from blast furnace gas ash(BFA).The reduction processes for Zn-containing and Fe-containing oxides were analyzed in deta...A high-temperature reduction roasting method was used to achieve metallic iron and zinc recovery from blast furnace gas ash(BFA).The reduction processes for Zn-containing and Fe-containing oxides were analyzed in detail by using ther-modynamic equilibrium calculation and the principle of minimum free energy.The results showed that the main reaction in the system is the reduction of ZnFe_(2)_(4)and iron oxides.Over the full temperature range,iron oxides were more easily reduced than zinc oxides.Regardless of the amount of CO contained in the system,the reduction of ZnO to Zn was difficult to proceed below the boiling point(906℃)of Zn.When the reduction temperature is below 906℃,the reduction process of zinc ferrate was ZnFe_(2)_(4)→ZnO;when the reduction temperature is above 906℃,its reduction process becomed ZnFe_(2)_(4)→ZnO→Zn(g).The metallization and dezincification rates of the BFA gradually increased with increasing reaction temperature.As the C/O ratio increased,the metallization and dezincification rates first increased and then decreased.The effect of reduction time on BFA reduction was similar to that of reaction temperature.展开更多
To solve the problem of low reduction extraction rate of zinc from blast furnace dust,the effects of CacO3 addition,reduction temperature,and reduction time on self-reduction zinc extraction were studied through high-...To solve the problem of low reduction extraction rate of zinc from blast furnace dust,the effects of CacO3 addition,reduction temperature,and reduction time on self-reduction zinc extraction were studied through high-temperature reduction experiment,and the mechanism of how CaCO_(3) addition promotes zinc ferrite reduction was analyzed.The zinc removal rate can reach 98.82%when the blast furnace dust is reduced at 1000℃ for 25 min by adding 10 mass%CaCO_(3).At low temperature,CaCO_(3) can enhance the reduction and decomposition of ZnFe_(2)O_(4)(which is difficult to reduce)into ZnO and low-valent iron oxides.After CaCO_(3) is decomposed at high temperature,CO_(2) is produced to undergo gasification reaction with carbon in blast furnace dust,and co is generated to provide more reducing agents for the whole reduction system.CaO generated by decomposition can also catalyze the gasification reaction of carbon,thus improving the removal rate of zinc in the reduction process of dust.展开更多
某高炉瓦斯灰粒度较细、成分较复杂,主要成分有氧化钙、赤铁矿、方解石、氧化锌、炭等,铁、锌、碳含量分别为27.44%、8.76%、13.51%,主要含锌矿物为氧化锌,含铁矿物为赤铁矿,碳主要以焦炭的形式存在。为确定硫酸浸取锌的合适硫酸浓度、...某高炉瓦斯灰粒度较细、成分较复杂,主要成分有氧化钙、赤铁矿、方解石、氧化锌、炭等,铁、锌、碳含量分别为27.44%、8.76%、13.51%,主要含锌矿物为氧化锌,含铁矿物为赤铁矿,碳主要以焦炭的形式存在。为确定硫酸浸取锌的合适硫酸浓度、液固比和浸出时间,进行了3因素3水平正交试验。结果表明,硫酸浓度对锌浸出率影响最显著,其次是液固比;在硫酸浓度为0.6 mo L/L、液固比为7 m L/g、浸出时间为25 min情况下硫酸浸锌,锌浸出率达97.03%。展开更多
基金This work was supported by the National Natural Science Foundation of China(Grant No.51704021)Key Research and Development Projects of Sichuan Province(021YFG0114)+1 种基金Key Research and Development Projects of Shandong Province(2021CXGC010209)the Joint Funds of the National Natural Science Foundation of China(U1560203).
文摘A high-temperature reduction roasting method was used to achieve metallic iron and zinc recovery from blast furnace gas ash(BFA).The reduction processes for Zn-containing and Fe-containing oxides were analyzed in detail by using ther-modynamic equilibrium calculation and the principle of minimum free energy.The results showed that the main reaction in the system is the reduction of ZnFe_(2)_(4)and iron oxides.Over the full temperature range,iron oxides were more easily reduced than zinc oxides.Regardless of the amount of CO contained in the system,the reduction of ZnO to Zn was difficult to proceed below the boiling point(906℃)of Zn.When the reduction temperature is below 906℃,the reduction process of zinc ferrate was ZnFe_(2)_(4)→ZnO;when the reduction temperature is above 906℃,its reduction process becomed ZnFe_(2)_(4)→ZnO→Zn(g).The metallization and dezincification rates of the BFA gradually increased with increasing reaction temperature.As the C/O ratio increased,the metallization and dezincification rates first increased and then decreased.The effect of reduction time on BFA reduction was similar to that of reaction temperature.
基金support by Nat-ural Science Basic Research Plan in Shaanxi Province of China(No.2019JLM-35)National Natural Science Foundation of China(No.51774224)Key Laboratory of Ecological Metallurgy of Mul-timetlie Mineral(Northeastem University)of Ministry of Education.
文摘To solve the problem of low reduction extraction rate of zinc from blast furnace dust,the effects of CacO3 addition,reduction temperature,and reduction time on self-reduction zinc extraction were studied through high-temperature reduction experiment,and the mechanism of how CaCO_(3) addition promotes zinc ferrite reduction was analyzed.The zinc removal rate can reach 98.82%when the blast furnace dust is reduced at 1000℃ for 25 min by adding 10 mass%CaCO_(3).At low temperature,CaCO_(3) can enhance the reduction and decomposition of ZnFe_(2)O_(4)(which is difficult to reduce)into ZnO and low-valent iron oxides.After CaCO_(3) is decomposed at high temperature,CO_(2) is produced to undergo gasification reaction with carbon in blast furnace dust,and co is generated to provide more reducing agents for the whole reduction system.CaO generated by decomposition can also catalyze the gasification reaction of carbon,thus improving the removal rate of zinc in the reduction process of dust.
文摘某高炉瓦斯灰粒度较细、成分较复杂,主要成分有氧化钙、赤铁矿、方解石、氧化锌、炭等,铁、锌、碳含量分别为27.44%、8.76%、13.51%,主要含锌矿物为氧化锌,含铁矿物为赤铁矿,碳主要以焦炭的形式存在。为确定硫酸浸取锌的合适硫酸浓度、液固比和浸出时间,进行了3因素3水平正交试验。结果表明,硫酸浓度对锌浸出率影响最显著,其次是液固比;在硫酸浓度为0.6 mo L/L、液固比为7 m L/g、浸出时间为25 min情况下硫酸浸锌,锌浸出率达97.03%。
