After the material becomes finer, many new properties will appear. Pigments, medicines, catalysts, fine ceramics, abrasives, magnetic materials, solid lubricants, metal powders and many other aspects require ultra-fine powders. Ultra-fine powder requires extremely fine particle size, uniform particle size distribution, and high product purity, so it is very important to select appropriate ultra-fine grinding equipment.

Jet mill

Grinding principle: impact, collision         Feeding size: <2mm         Product size d97/μm: 3~45

Advantage:

• The production process is continuous, the production capacity is large, and the degree of automation is high;
• The products processed by it have small particle size and narrow particle size distribution;
• High purity, especially suitable for crushing medicines and other materials that are not allowed to be contaminated;
• The particles have high activity and good dispersibility.

Shortcoming:

There is a blind zone inside, which will cause the phenomenon of failure to crush; there are certain requirements for the upper limit of the feed size, and it is difficult to crush the dense, fibrous, and flake materials.

Vibration mill

Grinding principle: friction, collision, shearing         Feeding size: <5mm          Product size d97/um: 3~74

Advantage:  Compact structure, small size, light weight, low energy consumption, high output, concentrated grinding particle size, simplified process, simple operation, convenient maintenance, and easy replacement of lining media

Shortcoming:  Distorted, weak strength; bearing is severely worn and easily damaged.

Stirring mill

Grinding principle: friction, collision, shearing         Feeding size: <1mm         Product size d97/μm: 2~45

Advantage:  Small footprint, uniform particle size distribution, ultra-fine product, low noise, high efficiency, energy saving, low pollution, and simple operation.

Shortcoming:  Due to the uneven energy input density and the secondary agglomeration of the powder, it is still basically grinding micron powder; due to the high-speed operation of the agitator, it is inevitable to produce wear and heat transfer problems, so this type of equipment is not suitable for grinding high Hard materials and heat-sensitive materials.

Colloid mill

Grinding principle: friction, shearing         Feeding size: <0.2mm         Product size d97/μm: ≤20

Advantage:

• Simple structure, convenient equipment maintenance;
• It is suitable for materials with higher viscosity and larger particles.

Shortcoming:  The material flow rate is not constant. For materials with different viscosities, the flow rate varies greatly; due to the high-speed friction between the rotor stator and the material, it is easy to generate greater heat and denature the processed material; the surface is easier to wear, and after wear, The refinement effect will be significantly reduced.

High-speed mechanical impact mill

Grinding principle: impact, impact, shear         Feeding size: <10mm         Product size d97/μm: 8~45

Advantage:

• Simple structure and easy operation;
• Small footprint and high grinding efficiency;
• Low equipment operating costs;
• It is more suitable for the deep processing of medium and low value-added non-metallic mineral products with medium hardness below 1000 mesh.

Shortcoming:  Because the high-speed operation of the machine will cause wear problems, it is not suitable for crushing materials with high hardness; tough materials have a strong absorption capacity for impact energy and are not easy to break, so materials with too high toughness should not be crushed by this type of mill; in addition, There is a problem of heat generation, and appropriate measures must be taken to crush heat-sensitive substances.

High pressure roller mill

Grinding principle: extrusion, friction         Feeding size: <30mm         Product size d97/μm: 10~45

Advantage:  The unit crushing energy consumption is low, the unit steel consumption is low, the unit processing capacity is large, and the crushed product has a uniform particle size. Small footprint and high equipment operation rate.

Shortcoming:  There will be edge effects, vibration and stuffiness, squeeze roller wear, etc.

High pressure water jet mill

Grinding principle: extrusion, friction         Feeding size: <0.5mm         Product size d97/μm: ≤45

Advantage:  It has strong dissociation, high efficiency, energy saving and low environmental pollution, and can significantly improve the labor environment.

Shortcoming:  The high-pressure water jet pulverization technology is still in its infancy, and the main application scope is only a few materials below the medium hardness, and the fineness after pulverization needs to be further improved. At the same time, the high-pressure water jet pulverization equipment has no competitive products.

Sanding machine

Grinding principle: friction, collision, shearing         Feeding size: <0.2mm         Product size d97/μm: ≤20

Advantage:  High production efficiency, strong continuity, low cost and high product fineness.

Shortcoming:  Not suitable for high-viscosity materials and requires pre-mixing.

Rotary Ball Mill

Grinding principle: friction, impact         Feeding size: <5mm         Product size d97/μm: 5~74

Advantage:  It is suitable for a variety of materials, can be produced continuously for a long time, has a large production capacity, can meet the needs of large-scale production, is easy to adjust the fineness of the product, and the maintenance and management are simple and easy to carry out. It has a good sealing device to prevent dust from flying.

Shortcoming:  The work efficiency is low, the body is heavy, the configuration is expensive, and the production cost is high.

Cyclone or cyclone flow self-mill

Grinding principle: impact, collision, shear, friction         Feeding size: <40mm         Product size d97/μm: 10~45

Advantage:  Low energy consumption, less auxiliary equipment, easy to realize production; automation, product granularity is relatively stable.

Shortcoming:  The liner wears quickly and is difficult to replace, and the hard ores are not easy to handle.

Grinding and peeling machine

Crushing principle: friction, collision, shearing         Feeding size: <0.2mm         Product size d97/μm: ≤20

Advantage:  High output, high stripping efficiency, fine product size, continuous production, and small floor space.

High-pressure homogenizer

Crushing principle: cavitation effect, leakage and shear         Feeding particle size: <0.03mm         Product particle size d97/μm: 1~10

Advantage:  Small footprint, high efficiency, large energy, fast response time, low operating cost

 

 

Article source: China Powder Network