Introduction of Pigment Powder Ultrafine Grinding Equipment
Particle size is one of the important indicators of pigments. Generally, it is required that the pigment particles have a stable physical form, uniform particle size, and good dispersibility without agglomeration or precipitation.
At present, common ultrafine grinding equipment includes air flow mill, mechanical impact ultrafine grinder, stirring ball mill, sand mill, vibration mill, colloid mill, high-pressure jet grinder, planetary ball mill, roller mill, ring roller mill, etc.
1. Air flow mill
Air flow mill is one of the most important ultrafine grinding equipment, and the product fineness can generally reach 1-45μm.
Working principle:
Use high-pressure air, inert gas or superheated steam to expand and cool down to form a high-speed flow field, drive the material particles to collide, rub and shear with each other in the jet flow field to achieve material refinement. Common types include flat type, fluidized bed reverse jet type, circulating tube type, opposite spray type, target type and dozens of specifications.
2. Mechanical impact ultrafine pulverizer
Mechanical impact ultrafine pulverizer is the ultrafine pulverizing equipment that is widely used in the domestic non-metallic mineral industry. The product fineness can generally reach d97=10μm, that is, the so-called 1250 mesh. It can produce ultrafine powder products with d97=5-7μm after being equipped with a high-performance fine classifier.
Working principle:
Using a rotating body (rod, hammer, blade, etc.) rotating at high speed around a horizontal or vertical axis, the feed is violently impacted, causing it to impact and collide with a fixed body or particles, and the ultrafine grinding equipment that crushes the particles with a stronger force has two crushing effects, impact and friction, and also has air flow crushing.
3. Stirring ball mill
A stirring ball mill is a type of ultrafine grinding equipment consisting of a stationary cylinder filled with grinding media and a rotating stirrer. The fineness of the product can reach less than 1μm.
Working principle:
The stirring medium is stirred by the stirrer to produce irregular motion, and the material is subjected to impact or shock, shearing, friction and other effects to crush the material, including intermittent stirring mill, continuous stirring mill, spiral stirring mill, tower mill, grinding and flaking machine, etc.
4. Sand mill
Sand mill is another form of stirred mill, named because it originally used natural sand and glass beads as grinding media. It can be divided into open type and closed type, each of which can be divided into vertical and horizontal types.
Working principle:
The slurry that has been stirred and mixed in the slurry barrel at high speed is pumped into the closed grinding chamber by pumping, and contacts with the high-speed rotating grinding media, so that the solid particles in the material and the grinding media produce stronger collision, friction and shearing effects with each other, so as to accelerate the grinding of particles and disperse aggregates.
Vibration mill is a fine grinding and ultrafine grinding equipment that uses grinding media (spherical or rod-shaped) to impact, rub, shear and other effects on materials in a high-frequency vibrating cylinder to crush the materials. It can process ultrafine powder products with an average particle size of 1μm or even less than 1μm. For materials with greater brittleness, submicron products can be obtained relatively easily.
6. Colloid mill
Colloid mill is a new type of equipment for wet ultrafine particle processing, suitable for various types of emulsification, dispersion, crushing and grinding. The particle size of the processed product can reach several microns to less than 1 micron.
7. High-pressure jet crusher
This type of equipment uses the strong impact force of the high-pressure jet and the cavitation effect after the pressure is suddenly reduced to crush the material due to impact and explosion. The average particle size of the product can be adjusted within the range of 1-20μm.
8. Ring roller mill, pressure roller mill
Ring roller mill and pressure roller mill both use material layer extrusion and crushing technology to achieve ultra-fine crushing of materials. That is, the material produces stress concentration under high pressure, causing cracks and expansion, and then produces numerous micro cracks, forming surface cracks and finally achieving material crushing.