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A Practical Approach for Recovering Iron from Waste Rock
Dump of Iron Ore Mine Using Novel Dry Magnetic Separation-
Industrial Scale Study
Rasool Hejazi, Leila Hosseini, S. Majid Saghaeian, M.Vahid Sheikhzadeh
Fakoor Sanat Tehran Company
ABSTRACT: Waste ores of iron ore mines, as important secondary source of iron, have outstanding latent
application value in iron recycling. In this study, a pilot and industrial-scale trial of iron recovery from iron
ore mine tailings using an innovative dry pre-concentration technology via novel magnetic separation was
investigated. Under optimal conditions in the pilot and industrial scale dry pre-concentration stage a high-
grade iron product containing more than 35% iron and k80 size index of 280 mm was obtained at 60.5% iron
recovery from a single feed with around 15% iron and top size of more than 1200 mm and k80 index of around
300 mm applying the new magnetic separation technology. .In the pre-concentration stage, most magnetite
and hematite ore in the waste rock dump of the iron ore mine were recovered as a high-grade product and used
as feed for the existing iron ore concentrate plant. Furthermore, production of final magnetite and hematite
concentrate from the pre-concentrate through additional grinding and wet magnetic separation by wet MIMS
and WHIMS were investigated. Under optimized conditions, a final concentrate with 65.53% iron grade,
44.81% yield and 83.73% iron recovery could be produced. With respect to the original iron ore waste, the
iron recovery was 50.53%. The newly developed well-functioning dry magnetic separator equipment showed
satisfactory performance, and controllable process parameters while producing the desired high-quality iron ore
product. This innovative technology plays an important role in the effective recycling of iron ore, opening up a
new approach for efficient recovery of iron from waste rock of iron ore mines.
Keywords: Waste, Iron Ore, Magnetic Separation, Low Grade, MIMS
INTRODUCTION
Magnetic separation is a long-established method for the
purification and removal of substances from fluids (Augusto,
P.A., Martins, J.P., 1999 Hoffmann, C., Franzreb, M., et
al., 2002), mainly as a commercial technology in mineral
processing industries ranging from steel production to coal
desulfurization (Svoboda, 1987 Augusto, P.A., Augusto,
P., Castelo-Grande, T., 2002.). Magnetic separation opera-
tions can be categorized into high intensity (up to 20,000
gauss) and low intensity (1,000–3,000 gauss) techniques
(Birss, R., Parker, M., Wong, M., 1979). Magnetic separa-
tors offer a simple, clean and economic way to sort mag-
netizable ores and minerals. In magnetic separation, the
difference in the susceptibilities of various particulate mate-
rials is used to separate the material flow into two or more
products (Wasmuth, H.D., and Unkelbach, K.H., 1991).
With the increasing demand for steel in the world, the
iron and steel industry has developed rapidly. Meanwhile,
a continuous increase of hazardous industrial wastes such
as waste of iron ore mines generated by the iron and steel
A Practical Approach for Recovering Iron from Waste Rock
Dump of Iron Ore Mine Using Novel Dry Magnetic Separation-
Industrial Scale Study
Rasool Hejazi, Leila Hosseini, S. Majid Saghaeian, M.Vahid Sheikhzadeh
Fakoor Sanat Tehran Company
ABSTRACT: Waste ores of iron ore mines, as important secondary source of iron, have outstanding latent
application value in iron recycling. In this study, a pilot and industrial-scale trial of iron recovery from iron
ore mine tailings using an innovative dry pre-concentration technology via novel magnetic separation was
investigated. Under optimal conditions in the pilot and industrial scale dry pre-concentration stage a high-
grade iron product containing more than 35% iron and k80 size index of 280 mm was obtained at 60.5% iron
recovery from a single feed with around 15% iron and top size of more than 1200 mm and k80 index of around
300 mm applying the new magnetic separation technology. .In the pre-concentration stage, most magnetite
and hematite ore in the waste rock dump of the iron ore mine were recovered as a high-grade product and used
as feed for the existing iron ore concentrate plant. Furthermore, production of final magnetite and hematite
concentrate from the pre-concentrate through additional grinding and wet magnetic separation by wet MIMS
and WHIMS were investigated. Under optimized conditions, a final concentrate with 65.53% iron grade,
44.81% yield and 83.73% iron recovery could be produced. With respect to the original iron ore waste, the
iron recovery was 50.53%. The newly developed well-functioning dry magnetic separator equipment showed
satisfactory performance, and controllable process parameters while producing the desired high-quality iron ore
product. This innovative technology plays an important role in the effective recycling of iron ore, opening up a
new approach for efficient recovery of iron from waste rock of iron ore mines.
Keywords: Waste, Iron Ore, Magnetic Separation, Low Grade, MIMS
INTRODUCTION
Magnetic separation is a long-established method for the
purification and removal of substances from fluids (Augusto,
P.A., Martins, J.P., 1999 Hoffmann, C., Franzreb, M., et
al., 2002), mainly as a commercial technology in mineral
processing industries ranging from steel production to coal
desulfurization (Svoboda, 1987 Augusto, P.A., Augusto,
P., Castelo-Grande, T., 2002.). Magnetic separation opera-
tions can be categorized into high intensity (up to 20,000
gauss) and low intensity (1,000–3,000 gauss) techniques
(Birss, R., Parker, M., Wong, M., 1979). Magnetic separa-
tors offer a simple, clean and economic way to sort mag-
netizable ores and minerals. In magnetic separation, the
difference in the susceptibilities of various particulate mate-
rials is used to separate the material flow into two or more
products (Wasmuth, H.D., and Unkelbach, K.H., 1991).
With the increasing demand for steel in the world, the
iron and steel industry has developed rapidly. Meanwhile,
a continuous increase of hazardous industrial wastes such
as waste of iron ore mines generated by the iron and steel