At present, there are about 300 kinds of iron-bearing minerals found in nature. According to the classification of chemical composition, the common iron ore mainly includes magnetite, hematite, limonite and siderite. Different properties of iron ore, its processing technology is naturally different. Below, we will explain to you the different types of iron extraction processes.
According to the different types of iron-bearing species, the magnetite can be divided into single magnetite and polymetallic magnetite. In general, the low intensity magnetic separation process is often used for the separation of single magnetite, while the combined process is often used for the separation of polymetallic magnetite.
Most of the iron minerals in the single magnetite ore are magnetite, which have simple composition, strong magnetism, easy grinding and easy separation, so the low intensity magnetic separation process is often used for separation of single magnetite.
The gangue of the polymetallic magnetite ore often contains silicate or carbonate minerals, and is associated with cobalt-pyrite, chalcopyrite and apatite. Generally, the combined process of low intensity magnetic separation and flotation can be used to deal with the polymetallic magnetite.
As a weakly magnetic iron ore, the hematite contains a small amount of magnetite, uneven dissemination size of impurity and more fine particles. Due to its complex ore properties, the gravity separation, flotation, magnetic separation and the combined process are often used for separation.
The hematite gravity separation process mainly includes coarse gravity separation and fine gravity separation.
The flotation process is mainly used for the separation of fine and fine weakly magnetic hematite ore, including positive flotation process and reverse flotation process.
Hematite low intensity magnetic separation-high intensity magnetic separation process;
Hematite high intensity magnetic separation-flotation process;
Hematite high intensity magnetic separation-gravity separation process;
Hematite roasting- magnetic separation process.
Limonite is a typical refractory iron ore, which is easy to slime and has poor separation index. The common limonite extraction processes mainly include gravity separation, magnetic separation, flotation and combined process.
In general, the limonite gravity separation is often used to treat the coarse-grained disseminated ores. This limonite extraction method has the advantages of simple equipment, low cost and less power consumption, but its recovery rate is low and grade of tailings is high.
Because the limonite contains iron, the difference in iron content leads to the difference in magnetic properties. Generally, the high intensity magnetic separation is used to separate limonite.
The single flotation method has a good recovery effect for the fine iron minerals, but limonite is easy to slime, which can seriously affect the flotation effect. Therefore, the desliming or strengthening slime disperse can be adopted before the flotation.
gravity separation- high intensity magnetic separation process;
Selective flocculation flotation process;
flocculation- high intensity magnetic separation process;
As a common weak magnetic iron ore, siderite is very difficult to extracted. At present, the common siderite extraction processes mainly include gravity separation, high intensity magnetic separation, flotation, magnetic roasting-low intensity magnetic separation process.
The gravity separation process is suitable for the coarse and medium-grain disseminated siderite. There are two main siderite gravity separation processes: heavy medium separation and jigging separation.
The flotation process is mainly used to separate the fine siderite, including positive flotation and reverse flotation.
There are two main separating solution for Pyrite, gravity separation and flotation separation. Gravity separation is most commonly used.
Gravity separation characterized by high efficiency and energy saving, which is most highly used in mineral process, since it is strongly practicability and has more effects than separation in mining efficiency and mining index. For less investment and mineral cost as well as little pollution, gravity separation is more suitable for coarse particle size pyrite processing.
As flotation also can be used for pyrite ore separation, though flotation separation has deficiency with considerable large investment in equipment, higher mining cost, while better efficiency and index in mining with simple flotation reagents, so flotation methods can be used for low grade pyrite ore.
Mongolia 3,500tpd Iron Ore Mining and Mineral Processing Plant
Process: Three-stage crushing and screening- stage-grinding and stage-separation- concentrates and tailings dewatering.
Shanxi 1,200t/d Iron Mineral Processing Plant
Process: Two-stage closed-circuit crushing and screening - two-stage closed-circuit grinding and classification - magnetic separation process of one-stage roughing and three-stage concentration - concentrates and tailings filtering and dewatering.
Xinjiang 3,300t/d Iron Mineral Processing Plant
Process: Full closed circuit of three-stage grinding and six-stage separation-concentrates dewatering-tailings dewatering.