October 10, 2024 – China’s Light Calcium Carbonate Industry Strives for Quality Improvement and Diversification
China’s light calcium carbonate industry boasts an impressive scale, with an annual production capacity exceeding ten million tons, securing its position as the global leader in both production and consumption. However, compared to developed countries, China still lags behind in product quality and variety, resulting in a relatively lower output value. In light of this, enhancing the quality of light calcium carbonate and developing specialized and functional products have become urgent tasks for propelling the industry’s development.
To effectively elevate the quality of light calcium carbonate, the industry must embark on multifaceted reforms. A primary focus is the innovation of calcination processes, shifting from traditional mixed-material calcination to intermittent or direct-fired methods. Currently, most Chinese light calcium carbonate manufacturers employ mixed-material vertical kiln calcination, which is plagued by issues such as coal slag pollution, impaired lime activity, and difficult temperature control. To overcome these drawbacks, the adoption of advanced equipment like new-type vertical kilns, rotary kilns, suspension calciners, and vortex dynamic calciners is recommended. According to AsiaMB, these devices exhibit notable advantages in fuel efficiency, calcination effectiveness, and product quality. Particularly, suspension calciners and vortex dynamic calciners, due to their high efficiency, environmental friendliness, and automation levels, are gradually becoming the industry’s favorites.
Moreover, the reform of carbonization processes is equally urgent. The intermittent carbonization process, though widely used due to its low investment and simple operation, suffers from issues such as uneven carbonization, wide particle size distribution, and unstable quality. Therefore, the industry should promote continuous carbonization processes, such as adopting multi-tower series continuous carbonization systems and efficient carbonization equipment like rotary spray carbonization towers and vertical sieve plate carbonization towers. These advancements aim to enhance carbonization efficiency and produce ultra-fine or nano-scale light calcium carbonate products.
The drying process, though seemingly straightforward, significantly impacts energy consumption and product quality. Traditional drying equipment is characterized by high energy consumption, easy alkalinity reversal, and pollution. Consequently, the adoption of new drying equipment, such as rotary dryers, rotary tube dryers, and disk continuous dryers paired with gas generators, has become crucial for improving product quality and reducing energy consumption. These devices not only offer high thermal efficiency but also facilitate automation, helping to eliminate environmental pollution.
Lastly, the surface treatment of light calcium carbonate cannot be overlooked. Due to its high surface energy, strong hydrophilicity, and significant thermal expansion coefficient difference with polymers, surface treatment is essential to improve its compatibility with polymers. Both dry and wet surface modification techniques can effectively enhance the dispersibility and affinity of light calcium carbonate, ensuring excellent physical and mechanical properties of the final products.
In summary, to enhance product quality and develop specialized and functional products, China’s light calcium carbonate industry must address multiple aspects, including calcination, carbonization, drying, and surface treatment. By adopting advanced processes and equipment, the industry can achieve comprehensive upgrading. Simultaneously, the industry should actively promote successful advanced experiences, elevate the overall process and equipment levels, and jointly drive the thriving development of China’s light calcium carbonate industry.