Hydrocyclones

History of development

Hydrocyclones* appeared in the Netherlands as early as the end of the 30s of the 20th century. Hydrocyclone is the use of rotary flow for grading equipment, and also used for concentration, dehydration and sorting, its structure is very simple, mainly composed of a hollow cylinder L and cone 2 connected. The diameter of the cylinder represents the specifications of the cyclone. Its size varies widely, from 50mm to 1000mm, usually 125-500mm.An overflow pipe 5 is inserted in the center of the cylinder, connected to the ore feed pipe 3 in the tangential direction, leaving a grit hole 4 in the lower part of the cone. Under the action of pressure, the slurry is fed into the cyclone along the feed pipe, and then rotates under the limitation of the cylindrical wall. The coarse particles are thrown to the wall of the vessel due to the large inertial centrifugal force, and gradually flow downward and are discharged from the bottom to become grit. The fine particles move towards the wall at a small speed, and are driven by the liquid flowing towards the center to flow out of the central overflow pipe and become an overflow.

peculiarity

Hydrocyclone is a kind of high-efficiency grading, demudging equipment, because of its simple structure, easy to manufacture, large processing capacity, has been widely used at home and abroad. Its main disadvantage is that it consumes a large amount of power and is seriously worn during high-pressure feeding. The use of new wear-resistant materials, such as cemented carbide, silicon carbide, etc. to make grit mouth and wear parts for the ore mouth, can partially solve this problem, in addition, when used for the classification of closed circuit grinding, because of its small volume, there is no buffer capacity for ore volume fluctuations, and it is not as stable as the mechanical classifier.

Brief introduction

A hydrocyclone is a device used to separate and remove heavier coarse-grained sediment and other substances from sewage. Sometimes it is also used for slurry dewatering. There are two types, pressure type and gravity type, often made of circular cylinder structure or metal pipe. Water enters tangentially by pressure or gravity from the upper part of the structure (or metal tube), and under centrifugal force, coarse and heavy particulate matter is thrown towards the wall and rotated downward to discharge with the formed concentrated liquid. The smaller particulate matter is rotated to a certain extent and then discharged with a secondary upward vortex.

Construction principle

The hydrocyclone consists of a hollow cylinder in the upper part and an inverted vertebral body communicating with the cylinder in the lower part, which constitute the working cylinder of the hydrocyclone. In addition, hydrocyclones also have feed pipes, overflow pipes, overflow pipes and grit outlets.

The hydraulic cyclone uses a sand pump (or height difference) to rotate the slurry into the cylinder in the tangential direction at a certain pressure (generally 0.5~2.5 kg/cm) and flow rate (about 5~12 m/s), and then the slurry rotates along the cylinder wall at a very fast speed to generate centrifugal force. By centrifugal force and gravity, coarser and heavier ore grains are ejected.

Hydrocyclones are mainly used in the mineral processing industry for grading, sorting, concentration and desilting. When the hydrocyclone is used as a classification equipment, it is mainly used to form a grinding classification system with the mill; When used as a desilting equipment, it can be used for desilting in a resorting plant; When used as a concentration and dewatering equipment, it can be used to concentrate beneficiation tailings and send it to fill underground mining tunnels.

The hydrocyclone has no moving parts and simple structure; The production capacity per unit volume is large and occupies a small area; High classification efficiency (up to 80%~90%), fine grading granularity; Low cost and low material consumption.