What Classification Equipment Is Used for Grinding?

Date: 2021-06-23     From: Longding     Author: admin

The closed-circuit grinding operation is inseparable from the classification equipment, which plays a role in improving the grinding efficiency and preventing over-crushing. The material discharged from the mill must immediately enter the classification equipment for classification. The separated qualified products enter the sorting process, and the coarse-grained products are returned to the ball mill for re-grinding. So what classification equipment can be used for grinding?

The classification equipment is used for grinding

1. Spiral classifier

Concentrators usually choose spiral classifiers, especially large-scale concentrators. No matter in structure or process, it is much superior to a rake classifier. The spiral classifier is composed of a U-shaped water tank, spiral device, transmission device, lifting mechanism, supporting bearing, and other parts. The spiral classifier is simple in structure, reliable in operation, convenient in elongation management and equipment configuration, and the classification area is relatively stable. Therefore, there are fewer ore particles with substandard particle sizes in the overflow. A large-scale ball mill is installed in the concentrator, and the spiral classifier can be used in combination with the self-flow ball mill. There is no need to install a sand pump to raise the slurry to a certain height.

2. Hydrocyclones

Hydrocyclones can also be used for grading, and are mainly composed of feeding pipes, cone containers, cylindrical shells, sand discharge nozzles, and overflow pipes. The hydrocyclone has a simple structure and a small footprint. It can be used directly with a sand washing machine, dewatering screen, etc.

3. Hydraulic classifier

The hydraulic classifier is widely used in preparatory operations before re-election, and can also be used as an auxiliary operation in the grinding process.

The hydraulic classifier is suitable for materials with a feed particle size of not more than 6 mm, preferably less than 2 mm. Generally used in grading operations before gravity sorting, such as shakers and chutes. When high classification efficiency is required, hydraulic classifiers are used.

How to choose the proper classification equipment?

At present, spiral classifiers and hydrocyclones are widely used in concentrators. There are few applications of hydraulic classifiers.

Compared with hydrocyclones, spiral classifiers are bulkier and have low classification efficiency. The grading particle size is coarse, especially when the overflow particle size is required-0.074mm accounted for more than 90%.

The hydrocyclone has a small footprint, high classification efficiency, and classification accuracy, and can completely replace the bulky spiral classifier in many large and medium-sized concentrators. However, the cyclone needs a stable working pressure, which requires high slurry particle size and concentration. The wear-resistant rubber lining can improve the problem of fast wear, increase the service life of the cyclone, and also have a certain lifting effect on the slurry.