11th International Symposium on High Temperature Metallurgical Processing: Utilization of Complex Ores
Sponsored by: TMS Extraction and Processing Division, TMS: Pyrometallurgy Committee
Program Organizers: Zhiwei Peng, Central South University; Jiann-Yang Hwang, Michigan Technological University; Jerome Downey, Montana Technological University; Dean Gregurek, RHI Magnesita; Baojun Zhao, Jiangxi University of Science and Technology; Onuralp Yucel, Istanbul Technical University; Ender Keskinkilic, Atilim University; Tao Jiang, Central South University; Jesse White, Kanthal AB; Morsi Mahmoud, King Fahd University Of Petroleum And Minerals
Thursday 2:00 PM
February 27, 2020
Room: 12
Location: San Diego Convention Ctr
Session Chair: Jerome Downey, Montana Technological University; Jiann-Yang Hwang, Michigan Technological University
2:00 PM Introductory Comments
2:15 PM
Ni Recovery from Nickeliferous Pyrrhotite Concentrates via a Thermal Concentration Process: Effects of Heat Treatment Time: Feng Liu1; Mansoor Barati1; 1University of Toronto
Nickeliferous pyrrhotite (Pyrr) tailings represent a promising Ni resource. Previous work has demonstrated that heating of nickeliferous Pyrr in the presence of suitable additives under a non-oxidizing atmosphere is capable of recovering the Ni value in the form of ferronickel alloy. In this study, the Pyrr concentrate, a flotation product of nickeliferous Pyrr tailings, was thoroughly mixed with metallic Fe and activated carbon, and then pressed into briquettes. The resultant briquettes were heat-treated at 900 °C for varying periods of time in Ar, followed by an Ar-quenching operation to retain the high-temperature structure. The calcine microstructure was examined as a function of treatment time, together with the composition of Ni-bearing phases. It was shown that progression of the iron sulfidization was companied by the formation of ferronickel alloy via multiple mechanisms, and prolonged treatment time promoted the uniformity of phase compositions and coarsening of alloy particles.
2:35 PM
Method to Quantify the Effect of Temperature and Rotational Speed on the Decrepitation of South African Manganese Ores in a Rotary Kiln: Samuel Moholwa1; Joalet Steenkamp1; Hillary Rutto2; Sifiso Sambo1; 1Mintek; 2Vaal University of Technology
Manganese ores are used as raw materials in the production of manganese ferroalloys. The lack of knowledge about mineralogical and metallurgical properties of manganese ores is a common problem in the production of these alloys. Decrepitation, which is the breakage of ores particles upon heating, is an important quality parameter. This work focuses on how the chemical, physical, and mineralogical properties of South African manganese ores and experimental parameters influence the decrepitation. The study is done on ore A, ore B and the blend of the two with a ratio of A to B being 60:40. After characterization the samples were then tested for decrepitation in a rotary kiln, temperature and rotational speed were varied between 600-1000°C and 5–20 rpm respectively, with the residence time of 30 minutes. The purpose of this paper is to describe the research method in detail and to report on preliminary results achieved
2:55 PM Cancelled
Production of High Carbon Ferrochromium by Carbothermal Reduction of Vanadium Extraction Tailings with High Chromium Content: Gaung Wang1; Jiang Diao1; Liang Liu1; Bing Xie1; 1Chongqing University
A novel method to smelt high carbon ferrochromium by synergistic reduction of vanadium extraction tailings with high chromium content and chromite is proposed in this paper. The recoveries of chromium and iron reach 95.79% and 98.06%, respectively, and decrease with the increase of mass ratio of chromite and tailings. The smelting time has little influence on the recoveries of chromium and iron, and the recoveries of chromium and iron are about 90.21% and 91.56%, respectively. The recoveries of chromium and iron decreased from 90.18% and 91.49% to 75.56% and 77.77% with the increase of reductant amount, respectively. The contents of chromium and iron in the high carbon ferrochromium product ranged from 47.00% to 52.00%, and 35.00 to 60.00%, respectively. The contents of impurity elements in the high carbon ferrochromium meet the expected requirements. The optimum smelting conditions are as follows: mass ratio at 5:1, smelting 10 min and C/O at 1.
3:15 PM Cancelled
Utilization of Ground Sinter Feed for Oxidized Pellet Production and Its Effect on Pellet Consolidation and Metallurgical Properties: Hongyu Tian1; Jian Pan1; Deqing Zhu1; Dingzheng Wang1; Yuxiao Xue1; 1Central South University
With the usage amount and purchase cost of pellet feed increasing, grinded sinter feed, as a relatively inexpensive and high-quality iron mine characterized by rich iron, poor silicon and low detrimental impurity, is a preferable alternative resource for pellet production. In this paper, the combined effects of grinded sinter feed proportion, binary basicity and MgO on roasting and metallurgical properties of pellets with maximally 40% ratio of grinded sinter feed were investigated. The results show that increasing the proportion of grinded sinter feed can optimize softening-melting properties, while impose a certain negative impact on compressive strength of fired pellets as well as reduction swelling. The adverse effects can be obviously improved by adding MgO and basicity optimization to produce fluxed magnesium pellets, which also illustrates the feasibility of adding high proportion of grinded sinter feed to the production of superior pellets for reducing the cost of raw materials.
3:35 PM Cancelled
Strengthening Sintering of Limonitic Nickel Laterite by Substituting Ferronickel Tailings for Sintering Fluxes: Yuxiao Xue1; Deqing Zhu1; Jian Pan1; Congcong Yang1; Hongyu Tian1; Dingzheng Wang1; Zhengqi Guo1; 1Central South University
Ferronickel tailings, by-products from nickel laterite direct reduction-magnetic separation process, are now stored up in large quantities with low utilization because of the high MgO content. In this paper, ferronickel tailing with 5.82% Fe, 0.51% Ni, 44.08% SiO2 and 31.98% MgO was adopted to replace the traditional Mg-bearing flux, i.e. serpentine. The laboratory pot sintering tests show that, this new technique increases sinter productivity and tumble index by 4.12% and 10.63%, respectively, and reduces solid fuel rate by 6.35%. The mineralogical study of product sinter shows that the addition of ferronickel tailing contributes to the increase of the amount of SFCA by 4.03%. Mg and Al elements were found to migrate into magnetite grains to form three types of spinel solid solutions, i.e. (Fe, Mg)Fe2O4, Fe (Fe, Al)2O4 and (Fe, Mg)·(Fe, Al)2O4. Meanwhile, eutectic compound melts were obtained by the co-melting of kirschsteinite (CaO·FeO·SiO2), monticellite (CaO·MgO·SiO2) and fayalite (2FeO·SiO2).