Iron Ore Beneficiation Process

Iron ore can be classified into two main types: strong magnetic iron ore and weak magnetic iron ore.

1. Strong magnetic iron ores: These include magnetite, titanomagnetite, and pyrrhotite. Magnetite is the most prevalent and contains iron tetroxide (Fe3O4) as its main iron mineral. It accounts for over 85% of all iron ore and exhibits strong magnetism, making weak magnetic beneficiation the primary method for processing these ores.
2. Weak magnetic iron ores: These include hematite, pseudo-hematite, limonite, siderite, and ilmenite. Hematite, limonite, and siderite are the main types of iron minerals found in weak magnetic iron ore. Different beneficiation processes can be employed based on their characteristics.

• Magnetite: Weak magnetic beneficiation is the primary method due to its strong magnetism.
• Ilmenite: The common beneficiation processes are “gravity separation-strong magnetic separation-flotation” or “gravity separation-strong magnetic separation-electric separation (pre-separation sulfur removal).”
• Limonite: Washing-gravity separation is commonly used. The ore is washed using equipment like washing machines before undergoing gravity separation using heavy media and jigs.
• Siderite: Gravity separation and strong magnetic separation are the commonly used methods for beneficiation, as siderite is a low-grade iron carbonate mineral.

By considering the unique properties of different iron ores, appropriate beneficiation processes can be selected to achieve optimal results.

Iron Ore Processing Plant

The iron ore beneficiation process involves various steps such as crushing, screening, grinding, classification, separation, and mineral dehydration. Its main objective is to separate minerals from the gangue, allowing for the final separation operation and preparing the minerals for further processing.

1. Iron Ore Washing Plant

The main machines involved in the iron ore washing plant setup, which is designed to process iron ore within the size range of 0-230mm, include:

1. Jaw crusher
2. Spiral sand washing machine
3. Vibrating screen
4. Ball mill
5. Spiral classifier
6. Magnetic separator

These machines work together in a coordinated manner to effectively wash and purify the iron ore.

The iron ore washing plant setup comprises various main machines to efficiently process the iron ore. To automatically feed the materials to the jaw crusher, a hopper and vibration feeder with a grizzly bar are used. The feeder also sifts the materials and sieves the size range of 0-50mm, which is then directed to the spiral washing machine. Loading of materials to the hopper can be done conveniently using a truck, excavator, or any suitable method.

The primary function of the jaw crusher is to crush the iron ore within the range of 50-230mm. However, for further refinement, the crushed ore is directed to a fine jaw crusher. Simultaneously, the spiral washing machine is employed to wash the materials sized between 0-50mm before being sent to the fine jaw crusher.

The role of the fine jaw crusher is to further crush the iron ore to a size of 0-20mm, making it suitable for the subsequent process in the ball mill. The vibrating screen is used to separate the materials sized between 0-20mm, directing the undersized materials to the ball mill and sending the oversized particles (+20mm) back to the fine jaw crusher for further crushing.

To enhance the smooth flow of materials to the ball mill, a hopper and feeder mechanism are utilized.

The ball mill and spiral classifier work in tandem to grind the iron ore and ensure the final product size is reduced to 0-0.074mm. Finally, the magnetic separator is used to separate and extract the iron concentrate from the processed material.

The capacity of the iron ore washing plant setup can be customized as per specific requirements, such as 10tph, 50tph, 100tph, and so on. It is important to note that if the materials being processed are not very sticky, the use of a spiral washing machine may not be necessary. The quantity and configuration of the machines mentioned above are provided as a reference and can be adjusted according to the desired capacity of the plant.

2. Iron Ore Crushing Plant

The 500tph iron rock ore processing plant consists of the following main machines:

1. Jaw crusher
2. Cone crusher
3. Double roll crusher
4. Vibrating screen
5. Dry magnetic separators
6. Iron ore crushing plant

The raw ore is composed of rock iron ore with a magnetite (Fe3O4) composition. It needs to be crushed to a size of 5mm in order to release the iron contained within it. The processing capacity of the plant is 500tph, and it is designed for a dry process.

1. Raw ore is transported by a dump truck and fed into the hopper, which then transfers it to the vibrating feeder.
2. The vibrating feeder evenly feeds the jaw crusher, which reduces the size of the ore to less than 200mm.
3. The output from the jaw crusher is conveyed to an underground transit silo using a belt conveyor. An electromagnetic vibrating feeder is installed beneath the silo.
4. The electromagnetic vibrating feeder feeds the output, which is larger than -200mm, to the first coarse cone crusher, reducing it to less than 100mm.
5. The cone crusher output is transported to the first and second vibrating screens via a belt conveyor. The vibrating screens have a two-layer design with mesh sizes of 5mm and 20mm.
6. Material larger than 20mm is sent back to the other two fine cone crushers for re-crushing. Material smaller than 5mm is sent to the first and second magnetic separators.
7. Material between 5-20mm is transferred to four double roll crushers via a belt conveyor. The double roll crushers further crush the ore to a size of 0-5mm.
8. The output from the double roll crushers is sent to the second and third vibrating screens. These screens have a single layer design with a 5mm mesh size.
9. Material larger than 5mm is returned to the double roll crushers for reprocessing.
10. Material smaller than 5mm is transferred to the first and second magnetic separators.
11. The output from the first and second magnetic separators is sent to the third magnetic separator for further separation, with a focus on concentrating iron.
12. The iron concentrate and tailings are then transported to the stockpile using belt conveyors.