KURIMOTO Co-LAB English|Kneading, Grinding, Drying

Calcium carbonate

碳酸钙 / Kalziumkarbonat / 탄산칼슘

Calcium carbonate
Description of Final products

A material primarily composed of calcium carbonate. In nature, it occurs as limestone and as a constituent of eggshells, seashells, and coral. It is available in various particle forms, including powder, granules, and cylindrical shapes.

Applications

Applications include fillers for paper, plastics, and coatings, as well as fertilizers, animal feed, cosmetics, and food additives.

Manufacturing process1 (Ground calcium carbonate )

※This process is just one example, and the manufacturing methods vary by company.

Raw material to be processed (limestone)
Crushing
The material is crushed into the specified shape using a crusher or similar equipment.
Sieving
Granular materials of several millimeters in size are separated by sieving.
Grinding
The material is ground to the specified particle size.
課題

If coarse particles are mixed in during grinding, they may adversely affect the downstream processes. Materials used for the parts that come into contact with the raw material during grinding are required to have high wear resistance.

解決策

The vertical roller mill "VX Mill" allows grinding and particle size adjustment, by the following characteristics.

VXミル ローラとテーブル

Roller pressure and table speed are adjustable to achieve the target particle size.

VXミル 分級機

By adjusting the rotational speed of the classifier, the inclusion of coarse particles can be prevented.

VXミル 耐摩耗鋳鉄

Wear-resistant cast iron is used for the material-contact parts. These components are also easy to replace.

Classifying
Fine particles are separated using a classifier, cyclone, or sieve.
Finished products

Manufacturing process2 (Precipitated calcium carbonate )

※This process is just one example, and the manufacturing methods vary by company.

Raw material to be processed (limestone)
Grinding
The material is ground to the specified particle size.
Calcining
Limestone is calcined to remove carbon dioxide (decarbonation), producing quicklime (calcium oxide).
Hydration
Quicklime is reacted with water to produce a slurry of slaked lime (calcium hydroxide).
Carbonating
CO₂ generated during calcination is added to the calcium hydroxide slurry, precipitating fine calcium carbonate particles in the liquid.
Dehydration
The solid and liquid are separated to recover fine calcium carbonate particles.
Drying
The fine calcium carbonate particles are dried by heating to produce a powder.
Disintegration
Agglomerates are broken up and classified to the specified particle size.
Finished products