Ground Calcium Carbonate

Ground Calcium Carbonate Introduction

Ground Calcium Carbonate (GCC for short) is calcium carbonate powder produced by mechanical crushing, grinding and classification of natural calcium carbonate minerals such as calcite, marble and limestone. Compared with precipitated calcium carbonate, ground calcium carbonate has advantages of simple production process, low energy consumption and low cost. It is widely used as filler and modifier in industrial fields including plastics, coatings, papermaking, rubber and building materials.

Powder Properties of Ground Calcium Carbonate

Chemical Properties: Calcium carbonate (CaCO₃) content ≥97.5%, stable chemical composition, high purity, low impurity content and good chemical inertness.

Material Properties: Fineness 80~400 mesh, uniform particle size, good flowability, easy to mix and disperse with matrix materials.

Appearance & Color: Whiteness generally ranges from 85~95, presented as uniform white powder. High-quality GCC can reach whiteness above 96.

Moisture Content: Free moisture ≤0.3%, effectively preventing caking and ensuring stability during storage and transportation.

Production Process of Ground Calcium Carbonate

For ground calcium carbonate powder of 80~400 mesh, Raymond mill is usually adopted for dry grinding. First, calcium carbonate minerals are coarsely crushed to ≤30mm by jaw crusher, then evenly and stably fed into Raymond mill by feeding conveyor for grinding. The fineness of finished calcium carbonate powder is precisely controlled by adjusting classifier rotation speed and fan air volume. While for ultra-fine ground calcium carbonate powder of 400~2500 mesh, ultra-fine grinding mill is required.

Application Fields of Ground Calcium Carbonate

Plastics Industry: Used as filler in PVC pipes, profiles, cable compounds and masterbatch. It can reduce product cost and improve rigidity, heat resistance and dimensional stability.

Coatings Industry: Applied in interior and exterior latex paint and powder coatings, improving hiding power, leveling property and scrub resistance of coatings and lowering formulation cost.

Papermaking Industry: Used as coating pigment and filler, increasing paper opacity, whiteness and printability and reducing pulp consumption.

Building Materials Industry: Used for artificial stone, putty powder and dry-mix mortar, boosting whiteness and strength of products and improving construction performance.

Technical Parameters of Ground Calcium Carbonate

Frequently Asked Questions of Ground Calcium Carbonate

What is the difference between Ground Calcium Carbonate and Precipitated Calcium Carbonate?

Ground Calcium Carbonate: Usually made from natural calcite, marble and limestone through mechanical crushing, grinding and classification. It features simple production process, low cost, low oil absorption value and high bulk density. Widely used as filler in plastics, coatings, papermaking, building materials and other industries.

Precipitated Calcium Carbonate (PCC): Generally produced from limestone via chemical precipitation processes including calcination, slaking and carbonization. Its microscopic morphology is spindle or chain shape, with high oil absorption value and low bulk density and relatively high production cost. It is mainly used as reinforcing agent in rubber, plastics, ink, toothpaste and other fields.

What should be noted during storage of Ground Calcium Carbonate?

Ground calcium carbonate has stable chemical properties and hardly reacts with moisture and carbon dioxide in air. Still, it should be stored in cool, dry and ventilated warehouse to avoid moisture and caking. Sealed packaging or ton bags are recommended. Stack height should not be too high to prevent compaction and caking. Its shelf life is generally 12 months. Re-inspection is suggested before use after expiration if qualified.

What is the difference between ordinary Ground Calcium Carbonate and ultra-fine Ground Calcium Carbonate?

Ordinary Ground Calcium Carbonate: Fineness 80~400 mesh, normally dry-ground by Raymond mill. Simple process, low cost and low oil absorption value. Mainly for filling and cost reduction, suitable for conventional calcium carbonate industrial applications.

Ultra-fine Ground Calcium Carbonate: Fineness 400~2500 mesh, processed by high-precision equipment such as ultra-fine grinding mill. Complex process, high added value and relatively high oil absorption value. Mainly for reinforcement and modification, suitable for high-end industries including plastics, coatings and rubber.