The spiral classifier commonly used in mineral processing is a mechanical classification device based on the principle that solid particles have different specific gravities and different precipitation speeds in liquids. The following is a detailed introduction to the spiral classifier for mineral processing:
Working principle of spiral classifier
In wet classification, the material is mixed with water and enters the spiral classifier. Through the rotation of the spiral blades and the flushing of water, the light and fine materials (such as fine sand and mud) overflow from the top of the trough with the water flow and become overflow products; while the heavy and coarse materials (such as coarse sand and stone) are discharged along the bottom of the trough under the push of the spiral blades, achieving effective separation. Dry classification mainly achieves the classification purpose through the blowing of air flow and the pushing action of spiral blades.
Types and characteristics of spiral classifiers
Spiral classifiers mainly include high weir single spiral and double spiral, submerged single spiral and double spiral, in addition to low weir (now rarely used) and XL spiral classifiers. The high weir type is good at separating ore particles with a particle size of more than 0.15mm and is suitable for use in the first stage of grinding; the submerged type is more suitable for separating ore particles with a particle size of less than 0.15mm, so it is often seen in combination with the mill in the second stage of grinding.
The spiral classifier has the characteristics of simple structure, reliable operation, and convenient operation. Its base is made of channel steel, and the body is welded with steel plates; the water inlet and shaft head of the spiral shaft are made of cast iron sleeves, which are wear-resistant and durable; the lifting device is divided into electric and manual types.
Application field of spiral classifier
Spiral classifier is widely used in many industries and fields. In mineral processing, it is mainly used for:
1. Ore dressing plant: used for the preliminary classification and concentration of ore to improve the efficiency of ore dressing. Specifically, it can be used to form a closed-loop cycle with a ball mill to separate and divert ore sand, or used in a gravity ore dressing plant to classify ore sand and fine mud, and to classify the ore pulp in the metal ore dressing process, and to remove mud and dewater in ore washing operations.
2. Coal processing plant: used for grading and dehydration of coal slime.
3. Chemical plant: used for grading and concentration of chemical raw materials.
Maintenance and troubleshooting of spiral classifier
In order to ensure the normal operation and extend the service life of the spiral classifier, it is necessary to perform regular maintenance and troubleshooting. Specific maintenance measures include checking the wear of the transmission device, spiral body, trough body and other parts, and replacing the seriously worn parts in time; cleaning the mud and debris on the water tank and spiral body; checking and adjusting the flexibility of the lifting device and the drain valve, etc.
In terms of troubleshooting, it is necessary to diagnose and eliminate the specific fault phenomenon. For example, when the spiral classifier vibrates or makes too much noise, it may be caused by looseness or wear of the transmission device or spiral body parts. It is necessary to check and tighten the relevant parts or replace the seriously worn parts.
The spiral classifier for mineral processing is an important grading equipment with a wide range of applications and market demand. During use, it is necessary to understand its working principle, structural characteristics, types and parameters, as well as maintenance and troubleshooting knowledge to ensure its normal operation and extend its service life.
