Recovery of γ-Fe2O3 from copper ore tailings by magnetization roasting and magnetic separation

Abstract To comprehensively reuse copper ore tailings, the recovery of γ-Fe2O3 from magnetic roasted slag after sulfur release from copper ore tailings followed by magnetic separation is performed. In this work, after analysis of chemical composition and mineralogical phase composition, the effects of parameters in both magnetization roasting and magnetic separation process with respect to roasting temperature, residence time, airflow, particle size distribution, magnetic field intensity, and the ratio of sodium dodecyl sulfonate to roasted slag were investigated. Under optimum parameters, a great number of γ-Fe2O3 is recycled with a grade of 66.86% and a yield rate of 67.21%. Meanwhile, the microstructure, phase transformation and magnetic property of copper ore tailings, roasted slag, and magnetic concentrate are carried out.

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Extraction of Nickel from Garnierite Laterite Ore Using Roasting and Magnetic Separation with Calcium Chloride and Iron Concentrate

Minerals ◽

10.3390/min10040352 ◽

2020 ◽

Vol 10 (4) ◽

pp. 352 ◽

Cited By ~ 3

Author(s):

Junhui Xiao ◽

Wei Ding ◽

Yang Peng ◽

Tao Chen ◽

Kai Zou ◽

...

Keyword(s):

Magnetic Separation ◽

Calcium Chloride ◽

Magnetic Field Intensity ◽

Mineral Phase ◽

Iron Mineral ◽

Nickel Recovery ◽

Iron Concentrate ◽

Iron Phase ◽

Roasting Temperature ◽

Laterite Ore

In this study, segregation roasting and magnetic separation are used to extract nickel from a garnierite laterite ore. The garnierite laterite ore containing 0.72% Ni, 0.029% Co, 8.65% Fe, 29.66% MgO, and 37.86% SiO2 was collected in the Mojiang area of China. Garnierite was the Ni-bearing mineral; the other main minerals were potash feldspar, forsterite, tremolite, halloysite, quartz, and kaolinite in the garnierite laterite ore. The iron phase transformations show that nickel is transformed from (Ni,Mg)O·SiO2·nH2O to a new nickel mineral phase dominated by [Ni]Fe solid solution; and iron changed from Fe2O3 and FeOOH to a new iron mineral phase dominated by metal Fe and Fe3O4 after segregation roasting. Ferronickel concentrate with Ni of 16.16%, Fe of 73.67%, and nickel recovery of 90.33% was obtained under the comprehensive conditions used: A roasting temperature of 1100 °C, a roasting time of 90 min, a calcium chloride dosage of 15%, an iron concentrate dosage of 30%, a coke dosage of 15%, a coke size of −1 + 0.5 mm, a magnetic separation grinding fineness of <45 μm occupying 90%, and a magnetic separation magnetic field intensity of H = 0.10 T. The main minerals in ferronickel concentrate are Fe, [Ni]Fe, Fe3O4, and a small amount of gangue minerals, such as CaO·SiO2 and CaO·Al2O3·SiO2.

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Production of Ferronickel Concentrate from Low-Grade Nickel Laterite Ore by Non-Melting Reduction Magnetic Separation Process

Metals ◽

10.3390/met9121340 ◽

2019 ◽

Vol 9 (12) ◽

pp. 1340

Author(s):

Guorui Qu ◽

Shiwei Zhou ◽

Huiyao Wang ◽

Bo Li ◽

Yonggang Wei

Keyword(s):

Magnetic Separation ◽

Separation Process ◽

Phase Changes ◽

Low Grade ◽

Nickel Laterite ◽

Nickel Laterite Ore ◽

Roasting Temperature ◽

Grinding Time ◽

Optimal Reduction ◽

Laterite Ore

The production of ferronickel concentrate from low-grade nickel laterite ore containing 1.31% nickel (Ni) was studied by the non-melting reduction magnetic separation process. The sodium chloride was used as additive and coal as a reductant. The effects of roasting temperature, roasting duration, reductant dosage, additive dosage, and grinding time on the grade and recovery were investigated. The optimal reduction conditions are a roasting temperature of 1250 °C, roasting duration of 80 min, reductant dosage of 10%, additive dosage of 5%, and a grinding time of 12 min. The grades of nickel and iron are improved from 2.13% and 51.12% to 8.15% and 64.28%, and the recovery of nickel is improved from 75.40% to 97.76%. The research results show that the additive in favor of the phase changes from lizardite phase to forsterite phase. The additive promotes agglomeration and separation of nickel and iron.

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Recovery a Refractory Oolitic Hematite by Magnetization Roasting and Magnetic Separation

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.361-363.305 ◽

2011 ◽

Vol 361-363 ◽

pp. 305-310 ◽

Cited By ~ 1

Author(s):

Chao Guo ◽

Hui Wang ◽

Jian Gang Fu ◽

Kai Da Chen

Keyword(s):

Magnetic Field ◽

Magnetic Separation ◽

Field Intensity ◽

Magnetic Field Intensity ◽

Reducing Agent ◽

Iron Concentrate ◽

Roasting Temperature ◽

Iron Grade ◽

Temperature Time ◽

Iron Ore Concentrate

Orthogonal test was carried out to investigate effects of multiple factors during the magnetization roasting-magnetic separation process as follow: roasting temperature, time, ratio of reducing agent and magnetic field intensity. Significant order of those factors on grade of iron concentrate is obtained, and opportune condition for magnetic roasting is determined. As the condition that roasting temperature is 850°C, time is 40min, ratio of reducing agent is mcoal/more=12% and magnetic field intensity is 1800Gs, iron ore concentrate whose grade and recovery are 56.32% and 94.03%, respectively, is obtained. At last, through closed-circuit test including magnetization roasting, magnetic separation and reverse flotation, final result is obtained that iron concentrate with phosphorus and silicon are 0.18% and 2.63%, respectively, and its iron grade and recovery are 60.47% and 80.1%, respectively.

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