In recent years, some new changes have taken place in the ultra-fine heavy calcium carbonate market. The most important features are: (1) Ultra-fine heavy calcium carbonate for paper coatings is mainly supplied from dry powder supply to high-solids slurry; 2 plastic film, high-grade coated paper and coated white paperboard and high-grade coatings to improve the particle size distribution of heavy calcium carbonate, such as: degradation of plastics, adhesives, engineering plastics, etc. required d97 = 6 ~ 7μm, dmax = 8μm, high Grade papermaking coatings require dmax=5μm, -2μm>93% or more; 3 require whiteness to reach 92% or more and be stable; 4 Due to the increase in the size and dosage of users (such as paper mills), ultrafine heavy calcium carbonate is required. The scale of production of goods manufacturers has expanded; 5 product prices have been blindly reduced due to market competition, and the benefits of heavy calcium plants have been seriously affected. These factors are extremely detrimental to the development of high-grade heavy calcium products.

　　In order to adapt to the changes in the above market, Yanshi Feilong Industrial Co., Ltd. took the product quality to meet the high standards of user demand in the development of ultra-fine heavy calcium carbonate product technology, and started to develop high-grade heavy calcium carbonate as the starting point. Advanced production equipment, using innovative production technology, reasonable selection of calcite raw materials, the first domestic high whiteness -2μm 93% grade, 79% solid content of high concentration surface coating heavy calcium by users.

　　1 Target the market and keep up with the high goals users need

　　Daewoo Paper Co., Ltd. is a joint venture between China and South Korea. It has domestic first-class modern equipment and technology, and produces high-grade art copper paper, with an annual output of 100,000 tons. The raw materials used by them, the raw material of calcium carbonate was converted from imported Japanese light calcium carbonate to imported OMYA heavy calcium carbonate until the company developed domestic high-grade heavy calcium dry powder to slurry high solid content heavy calcium, and completed a major quality. Change, historical breakthrough, through the use of our company's high-grade calcium products to make your company's product quality has been further developed, and made outstanding contributions to your company's consumption reduction and efficiency.

　　From the physical detection of its product indicators, its calcium has the characteristics of low viscosity, ultra-fine particle size, high solid content, stable product quality, etc. It is easy to disperse in the process of preparing the coating, which is beneficial to improve the solid content of the coating. It also has good rheological properties, which reduces the labor of production operators and improves production efficiency.

　　From the paper-forming properties of the coated paper, the calcium paste maintains the hue of the powdery heavy calcium, has high opacity and good ink absorption, and has high gloss, high whiteness and good uniformity. The advantages of smoothness and so on have brought the quality of Daewoo Paper's products to a new level, and the product quality is more stable.

　　The above is the total evaluation of Daewoo Paper Co., Ltd. for the use of heavy calcium in Lanshi Feilong Industrial Co., Ltd. How does this product evaluation come from? The main reason is that our company's product technology development follows the user's standard for product demand. According to the user's product standard, the production equipment to the production process is modified and adjusted, for example: when the user When we need to supply high-solid content -2μm 93 grade calcium product, we are very close to the user to set up the factory. The design scale is based on the user's dosage. It is capable of producing high-quality ordinary heavy calcium carbonate with suitable particle size. Long-diameter ratio, low-speed and low-energy wet-grinding process, and the matching small mill transformation, reasonable equipment technology ratio, become a satellite calcium carbonate production supplier. Through the production test once reached the standard, its calcium index reached -2μm93%, -5μm100%, solid content reached 79%, viscosity was less than 0.500Pa·s, whiteness reached 94%, and the user applied the standard once.

　　As a result of the development of heavy calcium, absorbing the advanced experience at home and abroad, keeping up with the needs of users, the product standards are upscale, adapting to the needs of the market, and thus winning the market.

　　2 Pay attention to the rational choice of calcite raw materials

　　At present, the raw materials of domestic heavy calcium powder are formed by the regional metamorphism and thermal contact metamorphism of carbonate rock. The marble type calcite deposit and a few hydrothermal vein calcite deposits can use the mineral as calcite. Although there are differences in the physical and chemical indicators of the Fangfang marble in various mines in China, as long as the CaCO3≥98%, MgO≤0.5%, hydrochloric acid insoluble matter≤0.3%, whiteness≥92%, etc. meet the requirements. It can process high-grade heavy calcium products, but through the production practice of our company, it is necessary to process the heavy calcium products required for high-grade paper-grade surface coating -2μm93. The crystal structure and structural characteristics of calcite cannot be ignored, because the deep processing of minerals is carried out on minerals. The process of scientific and technological processing aims to prepare high-tech materials for market demand. Therefore, it is necessary to establish an understanding of the correlation between mineral composition, structure, performance and processing factors, in order to rationally design the deep processing process and achieve deep processing. Goals and value-added effects.

　　In the production practice, the calcite produced by the foreign mines has been tried. The CaCO3 content is over 99%, and the calcite with low acid insoluble matter, pure quality and whiteness is as high as 96% to 97%. However, the calcite recrystallized is coarse. Self-formed crystal, the crystal is in the shape of a prismatic body, and it is mostly formed into a polycrystalline twin crystal. The cleavage parallel prism body (1011) is a complete calcite ore. The raw material powder processed by the specified number is used for the wet grinding process to produce its products at high speed. The coating test of the copper paper machine is similar to the calcite produced by our company's mine. It is a fine-grained shape, a semi-automorphic crystal structure, a granular structure, a block-shaped ore material, and the products produced by the same process conditions are compared and found. The calcite wet-milled calcium product produced by our company's mine shows that the coating structure is flat and appears as a plate in the process of coating the porcelain clay. The surface of the particles is smooth, without edges and corners, good uniformity, tight light pressure, good Smooth, high opacity, high gloss, low wear, and blade wear up to standard. The pure quality, recrystallized coarse, cleavage and development of calcite in the coating, the performance of the multi-angle and wear, the uniformity is poor, low transparency has a greater impact on paper quality.

　　Through the deep processing practice of different calcite mineral structures and structures, we fully realize that the different structural and structural characteristics of minerals have great influence on the end products, especially in the hydrothermal vein calcite deposit and marble type recrystallization. The self-shaped crystal facet body, the calcite developed by the polycrystalline twin crystal is not easy to be processed into a high-grade surface-coated paper pigment. The reason is that ultra-fine pulverization is only a physical change in the mechanical processing of the mineral itself, and the mineral still retains its crystalline structure and structural features. Therefore, the choice of calcite mineral raw materials is still the same as the granular shape of the metamorphic crystal structure block structure of the marble.

　　3. Conclusion

　　(1) The development trend of production technology of ultra-fine heavy calcium carbonate should adapt to the high-end demand of the market.

　　(2) To produce high-grade heavy calcium products, we must select advanced production equipment and innovative technological conditions.

　　(3) The selection of raw materials for high-grade heavy calcium products is important for the physical and chemical indicators of marble, and its mineral structure and structural characteristics cannot be ignored.

　　(4) High-grade heavy calcium products The selection of raw material powder size in the wet grinding process is also very important.