Electroslag remelting(ESR) gives a combination of liquid metal refining and solidification structure control.One of the typical aspects of liquid metal refining during ESR for the advanced steel and alloy production i...Electroslag remelting(ESR) gives a combination of liquid metal refining and solidification structure control.One of the typical aspects of liquid metal refining during ESR for the advanced steel and alloy production is desulfurization.It involves two patterns, i.e., slag–metal reaction and gas–slag reaction(gasifying desulfurization).In this paper, the advances in desulfurization practices of ESR are reviewed.The effects of processing parameters, including the initial sulfur level of consumable electrode, remelting atmosphere, deoxidation schemes of ESR,slag composition, melting rate, and electrical parameters on the desulfurization in ESR are assessed.The interrelation between desulfurization and sulfide inclusion evolution during ESR is discussed, and advancements in the production of sulfur-bearing steel at a high-sulfur level during ESR are described.The remaining challenges for future work are also proposed.展开更多
Sulfides in the high-sulfur bauxite lead to serious steel equipment corrosion and alumina product degradation via theBayer process,owing to the reactions of sulfur and iron-containing phases in the sodium aluminate so...Sulfides in the high-sulfur bauxite lead to serious steel equipment corrosion and alumina product degradation via theBayer process,owing to the reactions of sulfur and iron-containing phases in the sodium aluminate solution.The effects ofiron-containing phases on the transformation of sulfur-bearing ions(S2?,223S O?,23SO?and24SO?)in sodium aluminate solutionwere investigated.Fe,Fe2O3and Fe3O4barely react with23SO?and24SO?,but all of them,particularly Fe,can promote theconversion of223S O?to23SO?and S2?in sodium aluminate solution.Fe can convert to3Fe(OH)?in solution at elevatedtemperatures,and further react with S2?to form FeS2,but Fe2O3and Fe3O4have little influence on the reaction behavior of S2?insodium aluminate solution.Increasing temperature,duration,dosage of Fe,mole ratio of Na2Ok to Al2O3and caustic sodaconcentration are beneficial to the transformation of223S O?to23SO?and S2?.The results may contribute to the development oftechnologies for alleviating the equipment corrosion and reducing caustic consumption during the high-sulfur bauxite treatment bythe Bayer process.展开更多
The concentrations of S2O3 2- and SO3 2- were measured in gold leaching systems,including thiosulfate system,polysulfide system and the modified lime sulfur synthetic solution(ML)system in the process of chemical reac...The concentrations of S2O3 2- and SO3 2- were measured in gold leaching systems,including thiosulfate system,polysulfide system and the modified lime sulfur synthetic solution(ML)system in the process of chemical reaction.The interactions among S2O3 2- ,SO3 2-and S 2-were discussed.The behavior mechanism of sulfur-bearing reagents was proposed to describe the process reactions and their Gibbs free energy.The proper quantity oxygen and SO3 2- reduce decomposition of S2O3 2-and react with sulfur derived from the decomposition of SX 2- .So,SO3 2-ions have action to stabilize sulfur-bearing system and are favorable to leach gold.展开更多
基金financially supported by the National Natural Science Foundation of China (Nos.51874026 and 52074027)the Fundamental Research Funds for the Central Universities (No.FRF-TP-18-004A3)the State Key Laboratory of Advanced Metallurgy of China (No.41619019)。
文摘Electroslag remelting(ESR) gives a combination of liquid metal refining and solidification structure control.One of the typical aspects of liquid metal refining during ESR for the advanced steel and alloy production is desulfurization.It involves two patterns, i.e., slag–metal reaction and gas–slag reaction(gasifying desulfurization).In this paper, the advances in desulfurization practices of ESR are reviewed.The effects of processing parameters, including the initial sulfur level of consumable electrode, remelting atmosphere, deoxidation schemes of ESR,slag composition, melting rate, and electrical parameters on the desulfurization in ESR are assessed.The interrelation between desulfurization and sulfide inclusion evolution during ESR is discussed, and advancements in the production of sulfur-bearing steel at a high-sulfur level during ESR are described.The remaining challenges for future work are also proposed.
基金Project(51604309)supported by the National Natural Science Foundation of ChinaProject(201509048)supported by the Environmental Protection’s Special Scientific Research for Chinese Public Welfare IndustryProject(2015CX001)supported by the Innovation-driven Plan in Central South University,China
文摘Sulfides in the high-sulfur bauxite lead to serious steel equipment corrosion and alumina product degradation via theBayer process,owing to the reactions of sulfur and iron-containing phases in the sodium aluminate solution.The effects ofiron-containing phases on the transformation of sulfur-bearing ions(S2?,223S O?,23SO?and24SO?)in sodium aluminate solutionwere investigated.Fe,Fe2O3and Fe3O4barely react with23SO?and24SO?,but all of them,particularly Fe,can promote theconversion of223S O?to23SO?and S2?in sodium aluminate solution.Fe can convert to3Fe(OH)?in solution at elevatedtemperatures,and further react with S2?to form FeS2,but Fe2O3and Fe3O4have little influence on the reaction behavior of S2?insodium aluminate solution.Increasing temperature,duration,dosage of Fe,mole ratio of Na2Ok to Al2O3and caustic sodaconcentration are beneficial to the transformation of223S O?to23SO?and S2?.The results may contribute to the development oftechnologies for alleviating the equipment corrosion and reducing caustic consumption during the high-sulfur bauxite treatment bythe Bayer process.
基金Project(2007ZDGC-11) supported by "13115" Science and Technique Innovation Program of Shaanxi Province, ChinaProject(09JK561) supported by Educational Commission of Shaanxi Province of China
文摘The concentrations of S2O3 2- and SO3 2- were measured in gold leaching systems,including thiosulfate system,polysulfide system and the modified lime sulfur synthetic solution(ML)system in the process of chemical reaction.The interactions among S2O3 2- ,SO3 2-and S 2-were discussed.The behavior mechanism of sulfur-bearing reagents was proposed to describe the process reactions and their Gibbs free energy.The proper quantity oxygen and SO3 2- reduce decomposition of S2O3 2-and react with sulfur derived from the decomposition of SX 2- .So,SO3 2-ions have action to stabilize sulfur-bearing system and are favorable to leach gold.
