Chrome Beneficiation Process

Chrome ore, also known as chromite, is often associated with ferrochromium and has a strong affinity for iron. Industrial-grade chrome ore typically contains a significant amount of chromium oxide, ranging from 18% to 62%, along with aluminum and nickel impurities. Various beneficiation processes are employed for chrome ore due to its unique properties, including gravity separation, magnetic separation, flotation, combined beneficiation, and chemical beneficiation. The choice of specific beneficiation process depends on the results of beneficiation testing.

Gravity separation, which offers low investment costs and rapid returns, is commonly used for chrome ore beneficiation. Equipment such as spiral chutes, shaking tables, and jig separators are frequently applied in the gravity separation stage. The selection of equipment for the magnetic separation stage depends on the magnetic properties of the ore. As a result, gravity and magnetic separation processes are commonly used in chrome ore beneficiation.

Chrome Ore Processing Plant

1. Alluvial Chrome Wash Plant

This is a complete alluvial chrome wash plant with a processing capacity of 150 tons per hour. The system includes a vibrating feeder, trommel screen, belt conveyor, slurry pump, and spiral chutes. Here are the details of the raw ore:

• Feeding capacity: 150 tons per hour
• Chrome concentrate size: Less than 2mm
• 0-2mm mineral content in raw ore: Approximately 70%
• No sticky clay content in the raw ore

The plant follows a free flow design with the following stages:

1. Feeding: The raw ore is delivered to the raw material hopper by an excavator or truck. It is then evenly fed into the trommel screen via a vibrating feeder. The vibrating feeder is equipped with a grizzly bar with a 75mm gap. Any rocks larger than 75mm are directed to a waste stockpile through a belt conveyor.
2. Washing stage: The ore with a size range of 0-75mm is sent to the trommel screen for sieving. The trommel screen separates the ore into two fractions: 0-2mm and 2-75mm. The particles sized 2-75mm are sent to a waste stockpile using a belt conveyor, while the particles sized 0-2mm go to a slurry tank.
3. Gravity separation: The chrome concentrate is obtained through gravity separation utilizing spiral chutes. The slurry pump is used to send the 0-2mm particles to the first stage spiral chute group for separation into chrome concentrate, middling, and tailing. The tailing is directed to a tailing pool. The middling from the first stage spiral chute group is then transferred to the second stage spiral chute group using a slurry pump for further processing, allowing for enhanced recovery of chrome concentrate.

This setup is suitable for large processing capacities and offers cost-effectiveness, resulting in a good recovery effect. By selecting the appropriate chrome mining equipment and designing the chrome wash process plant carefully, it is possible to improve the grade of chrome concentrate, maximize the utilization of chrome ore resources, and maximize your benefits.

2. Rock Chromite Processing Plant

For rock chrome ore processing, various chrome mining equipment such as crushing and grinding machines are required. This configuration is designed for a rock chrome processing plant and includes the following equipment:

• Vibrating feeder
• Jaw crusher
• Cone crusher
• Vibrating screen
• Ball mill
• Spiral chutes
• Shaking tables

The plant follows a free flow design and consists of the following stages:

1. Crushing stage: The raw ore stone is uniformly fed into the primary jaw crusher by a vibrating feeder, ensuring a smooth and even feed. The vibrating feeder is equipped with a grizzly bar to remove oversized material, which is directed to the primary jaw crusher. Small-sized material below the grizzly bar is sent to the fine crusher through a conveyor, enhancing the crushing effectiveness of the primary jaw crusher.
2. Screening stage: The primary jaw crusher reduces the size of the rock chrome ore to a smaller size, which is then transferred to the cone crusher for fine crushing. The cone crusher further crushes the rock chrome ore below 20mm. However, before entering the cone crusher, the material passes through a vibrating screen for the removal of oversize particles larger than 20mm, redirecting them back to the cone crusher for re-crushing. The undersize material of 0-20mm is directed to a storage bin before entering the ball mill.
3. Grinding stage: The undersize material of 0-20mm is smoothly conveyed to the ball mill by an electromagnetic vibrating feeder and belt conveyor. The ball mill then grinds the material into a fine powder. To ensure optimal process efficiency, the ball mill works in conjunction with a spiral classifier. The overflow slurry from the classifier contains approximately 80% 200mesh powder, while the oversize particles are recycled back to the ball mill for further grinding, creating a closed-loop system.
4. Recovery stage: The 200mesh slurry is pumped into the gravity separation machines, including spiral chutes and shaking tables. The spiral chute performs the primary concentration, and the heavy concentrate ore discharged from the two-stage spiral chutes is further processed on the shaking table to obtain a higher-grade chrome concentrate.

The capacity of this setup can be customized according to your requirements, ranging from 2tph to larger capacities. Additionally, if higher-grade chrome concentrate is desired, a high-intensity magnetic separator can be added in the final stage. This flexible plant design allows for customization based on the specific conditions of your rock chrome ore.