How to Make Paper Grade Ground Calcium Carbonate?
Paper grade Ground Calcium Carbonate(GCC) is one of the most important mineral fillers used in paper manufacturing. From office paper and coated paper to packaging paper and specialty paper, GCC has become the second most important raw material after paper fiber. It improves paper quality while significantly reducing production costs.
As paper manufacturers continue replacing expensive pulp with GCC, the demand for high-quality paper-grade calcium carbonate continues to grow worldwide.
However, not every calcium carbonate powder is suitable for papermaking. Paper manufacturers require high-purity, high-whiteness, and precisely controlled GCC to ensure consistent paper performance.
For your mining, mineral processing, and powder production business, this is not just a market. It is your opportunity to move from low-value raw material sales to high-value industrial supply. It is key for you to understand the quality requirements and select the right grinding equipment.
Why Does the Paper Industry Use GCC?
Ground calcium carbonate is widely used as both a filler and coating pigment in paper manufacturing. Its functions include:
In modern papermaking, GCC is not simply a filler. It is a key material that directly affects paper quality and production efficiency, as well as manufacturing cost.
What Kind of GCC Do Paper Mills Require?
Producing GCC for the paper industry is much more than simply grinding limestone. Paper manufacturers have strict quality standards when selecting GCC. From whiteness and purity to particle size distribution and impurity control, your GCC powder should comply with these strict specifications. These requirements directly determine whether your product can enter the high-end paper market.
Whiteness directly affects the appearance of finished paper. Higher whiteness helps manufacturers produce brighter paper with less optical brightener. Paper-grade GCC requires a whiteness above 92%. For the high-end coated paper manufacturing, it needs 94% to above 95% or even higher. The higher your whiteness, the higher the market value.
Paper-grade GCC generally requires a calcium carbonate content of 98% or higher. High purity improves paper brightness and minimizes abrasive impurities. Besides, it also helps ensure stable papermaking performance.
Different paper types require different particle sizes. For example, producing corrugated paper, 325-400 mesh GCC powder is applicable. Writing and copy paper use 500-800 mesh. As for the High-end printing and pre-coated paper, its requirement is higher, 1250-2500 mesh. For premium posters and top-tier coated topcoats, the ultrafine GCC powder under 2μm is required.
| Paper Type | Recommended GCC |
| Corrugated paper | 325–400 mesh |
| Copy paper | 500–800 mesh |
| Coated paper | 1250–2500 mesh |
| Premium coating | D97 <2 μm |
Besides particle size, paper manufacturers also require a narrow particle size distribution to achieve better coating coverage, smoother surfaces, and stable production.
Hard mineral impurities, such as quartz, increase equipment wear and may scratch paper surfaces. Typically, the paper-grade GCC requires hydrochloric acid insolubles below 0.35%. Lower abrasion also extends the lifetime of paper machine rolls, pumps and pipelines, and coating blades.
It should be mentioned that the heavy metal control is key for food packaging paper producing. When producing food packaging paper, heavy metals such as lead, mercury, cadmium, arsenic, and hexavalent chromium must be strictly controlled to meet safety standards.
How to Produce Paper Grade Ground Calcium Carbonate?
Meeting the quality requirements of paper-grade GCC is not simply grinding limestone into fine powder. High whiteness, high purity, consistent particle size distribution, and low impurity levels all depend on a well-designed production process.
A typical paper-grade GCC powder production line includes the following steps:
Raw Material Selection → Crushing → Grinding → Air Classification → Powder Collection → Automatic Packing
Raw Material Selection
Everything starts with the right raw materials. Choosing high-quality raw materials is the first step toward producing premium paper-grade GCC. For paper application,s high-quality limestone or chalk with high Caco3, high whiteness, and low silica impurities is preferred.
Crushing
Proper crushing reduces the feed size before grinding. This improves grinding efficiency and also lowers energy consumption and equipment wear.
Grinding
Crushed materials enter the grinding system to produce the required particle size. It’s the key process determining fineness, particle shape, whiteness stability, and energy consumption. Different grinding systems are suitable for different fineness requirements. Daswell Powder offers you various grinding mill machines from coarse powder to ultrafine powder production.
Classifying
For making sure the stable and uniform paper-grade GCC powder, the air classification machine can separate the qualified particles from oversized materials. Oversized particles are returned to the grinding system for further milling. This closed-loop process ensures a narrow particle size distribution. It is essential for achieving consistent paper opacity, brightness, smoothness, and printing performance.
Powder collection and packing
The finished powder is collected and automatically packed for transportation or supply to paper manufacturers. Our automated handling systems help maintain product cleanliness while improving production efficiency and reducing labor costs.
Which Grinding Mill Is Best for Paper Grade GCC?
Selecting the right grinding system is the key to balancing product quality, production efficiency, and operating cost. As a professional powder grinding solution supplier, Daswell Powder has various grinding mills for you to choose. How to choose the suitable grinding mill for your paper-grade GCC production.
Daswell Powder matches the grinding equipment to your target paper products, helping you achieve the required powder quality while maximizing production efficiency and profitability.
Just send a message to Daswell Powder, we can customize for your own paper-grade GCC powder production.
