Gas-Based Direct Reduction of Hongge Vanadium Titanomagnetite-Oxidized Pellet and Melting Separation of the Reduced Pellet

In this study, high-purity iron with purity of 99.987 wt.% was prepared employing a process of direct reduction–melting separation–slag refining. The iron ore after pelletizing and roasting was reduced by hydrogen to obtain direct reduced iron (DRI). Carbon and sulfur were removed in this step and other impurities such as silicon, manganese, titanium and aluminum were excluded from metallic iron. Dephosphorization was implemented simultaneously during the melting separation step by making use of the ferrous oxide (FeO) contained in DRI. The problem of deoxidization for pure iron was solved, and the oxygen content of pure iron was reduced to 10 ppm by refining with a high basicity slag. Compared with electrolytic iron, the pure iron prepared by this method has tremendous advantages in cost and scale and has more outstanding quality than technically pure iron, making it possible to produce high-purity iron in a short-flow, large-scale, low-cost and environmentally friendly way.

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Research on the melt behavior of rare-earth-rich iron minerals by direct reduction

Metallurgical Research & Technology ◽

10.1051/metal/2020009 ◽

2020 ◽

Vol 117 (1) ◽

pp. 118

Author(s):

Wentao Guo ◽

Zhi Wang ◽

Zengwu Zhao ◽

Wenfeng Wang

Keyword(s):

Rare Earth ◽

Phase Structure ◽

Carbothermic Reduction ◽

Direct Reduction ◽

Graphite Crucible ◽

Reduction Degree ◽

Mineral Phase ◽

Iron Mineral ◽

P Content ◽

Melting Separation

The evolution of mineral phase structure during the reduction and melting separation of an rare earth (RE)-rich iron mineral (RER-IM) is investigated. The results show the iron oxides are reduced to their metallic iron or FeO at 1373 K. When reduction time is 180 min, the reduction degree is 84%. Both bastnaesite (RE(CO3)F) and monazite (REPO4) are transformed into Ca2RE8(SiO4)6O2 during carbothermic reduction at 1373 K. The mineral with a reduction degree of 84% is melt-separated in a graphite crucible at 1773 K for 20 min, the resulting slag contains 20.64% RE2O3, with RE existing in the form of Ca2RE8(SiO4)6O2. Moreover, P from the reduction of Ca3(PO4)2 dissolves in iron with a content ranging from 1.2 to 2.21%. The type of RE phase that occurs in the slag is related to the distribution of P between slag and iron. A low P content in the slag facilitates the formation of Ca2RE8(SiO4)6O2, but a high content in the slag favours Ca3RE2[(Si, P)O4]3F. Thus, it is confirmed that the RE phase structure is controlled by the distribution of P between slag and iron.

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ON THE PROCESSING OF HEMATITE RAW MATERIALS AT THE KRYVOROZHSK MINING AND PROCESSING PLANT OF OXIDIZED ORE ON TECHNOLOGY OF DIRECT RECOVERY ITmk3

Metallurgicheskaya i gornorudnaya promyshlennost ◽

10.33101/s005-59768574 ◽

2018 ◽

pp. 32-37

Author(s):

P.I. Loboda ◽

Younes Razaz ◽

S. Grishchenko

Keyword(s):

Magnetic Properties ◽

Cast Iron ◽

Iron Content ◽

Raw Materials ◽

Direct Reduction ◽

Processing Plant ◽

High Iron Content ◽

High Iron ◽

Direct Restoration ◽

First Time

Purpose. To substantiate the efficiency of processing hematite raw materials at the Krivoy Rog Mining and Processing Plant of Oxidized Ores using the direct reduction technology itmk3®. Metodology. Analysis of the results of the itmk3® direct restoration technology developed by Kobe Steel Ltd., Japan and Hares Engineering GmbX, Austria, with a view to using it to process Krivbass hematite ores into granulated iron (so-called “nuggets”). Findings. The involvement in the production of hematite ores (oxidized quartzite) of Krivbass with high iron content, but with low magnetic properties for their processing into granular cast iron is grounded. Originality. The use of itmk3® direct reduction technology from Kobe Steel Ltd., Japan and Hares Engineering GmbH, Austria for the processing of Krivbass hematite ores into granular cast iron is justified for the first time. Practical value. The efficiency of the use of hematite ores (oxidized quartzite) has been substantiated, which can significantly reduce the costs in the mining cycle for the economical production of metallurgical products.

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