Calcium carbonate manufacturer: Application and characteristics of calcium carbonate as a filler in the papermaking industry; Currently, in the papermaking process, the amount of filler and pigment used is second only to fiber, making it the second most important raw material. Commonly used papermaking fillers include calcium carbonate, talc, kaolin, wollastonite, bentonite, etc. With the gradual shift from acidic papermaking processes to neutral and alkaline papermaking processes, Guangxi Longhua calcium carbonate, as an important papermaking raw material, is being used more and more in the papermaking industry.

　　Papermaking fillers are fine, white mineral powders that are generally insoluble or slightly soluble in water. The main purposes of adding fillers to paper are: Fillers are dispersed between pulp fibers to fill the gaps, improving the opacity and whiteness of the paper; Improve the ink absorbency of the paper, making the paper have better printability; Meet certain special performance requirements of the paper, such as improving the conductivity and heat resistance of the paper; Reduce the use of fiber raw materials and reduce production costs; Fillers have a large specific surface area, which helps to overcome resin barriers.

　　Filler addition methods are divided into batch and continuous methods. Batch filling is used in batch pulping or batch pulp preparation and conditioning sections. When using a trough pulper, it is added to the pulper after pulping is complete. Using continuous pulping equipment, it is usually added to the pulp preparation tank or pulper. Continuous filling is the continuous addition of filler slurry in the pulp supply system. It is generally added at the outlet of the high-level pulp stabilization tank, which ensures uniform mixing and prevents the decomposition of calcium carbonate filler due to acidic papermaking.

　　The advantages of Guangxi Longhua calcium carbonate used as a papermaking filler are: abundant sources, low price; fine particles, high whiteness, significantly improving the opacity of paper; fast ink absorption speed, increasing the ink absorbency of paper; making the paper relatively soft, dense, and high gloss; having a relatively small impact on the physical strength of the paper.

　　The Chinese chemical industry standard QB/T2811-2019 stipulates the technical requirements of calcium carbonate filler for papermaking. Light calcium carbonate used as a papermaking filler is available in powder, paste, and slurry forms, while heavy calcium carbonate is available in powder and slurry forms. The main quality indicators include purity, D65 brightness, pH value, hydrochloric acid insoluble matter, viscosity, and particle size distribution. The amount of filler added is mainly determined by factors such as the type of paper, the type of pulp, the properties of the filler itself, and the paper machine's papermaking conditions. In order to save plant fibers and reduce production costs, the amount of filler added should be appropriately increased on the premise of ensuring the papermaking and use requirements. The amount of calcium carbonate filler added to the main paper types.

　　Guangxi Longhua heavy calcium carbonate as a filler is mainly used in printing paper, writing paper, office paper, and advertising paper, except for cigarette paper, filter paper, and special low-grammage information paper. Light calcium carbonate can be used in principle in all types of paper, and is currently mainly used as a filler for high-grade paper. For example: cigarette paper, office information paper (such as fax paper, instrument recording paper, inkjet printing paper), low-grammage newsprint, low-grammage coated paper, etc.

　　Guangxi Longhua heavy calcium carbonate and Guangdong light calcium carbonate have their own advantages as papermaking fillers, therefore, the choice of calcium carbonate should be determined according to the actual paper production process requirements.