There are eight important indicators in heavy calcium carbonate


release time:

2022-01-19

1. Whiteness: The whiteness is mainly related to the origin of the calcium carbonate ore, the composition of the ore, and the type of the ore. Generally speaking, the higher the whiteness, the higher the calcium carbonate content, and the whiteness mainly affects the whiteness, gloss and colorability of plastic products. There is also a hue problem in whiteness. Because the calcium carbonate ore contains some other elements, there are also certain differences in the hue of calcium carbonate from different origins, mainly reddish, blueish, and yellowish. Several common hue.

2. Particle size and particle size distribution: Particle size mainly refers to the size of particles. Particle size distribution refers to the proportion of particles of various sizes to the total number of particles in a powder sample. We often use "mesh" to represent the fineness of the powder, and the corresponding particle size is represented by D97, but a simple D97 is not enough to represent the fineness of the powder, and a complete particle size distribution should be used. The graph can characterize the characteristics of fineness. In plastic products, the narrower the particle size distribution of calcium carbonate, the more stable the processing industry and product quality; the wider the particle size distribution, the easier it is to process difficulties and unstable product quality.

 

 

3. Specific surface area: The specific surface area of ​​a powder sample refers to the sum of the surface areas of all particles in the sample per unit mass. Generally speaking, the finer the fineness, the larger the specific surface area, but the content of coarse powder and fine powder also needs to be considered. If the fine powder content is high, but its D97 value is large, the fineness will be large and the specific surface area will be large. At the same time, when judging the specific surface area, it is also necessary to consider the particle surface morphology and whether the particle is a solid body. If the particle surface has many pores or surface depressions, the measured specific surface area is also too large. Generally, the larger the specific surface area, the higher the gloss of the product, but its dispersibility is also more difficult.

 

 

4. Oil absorption: Oil absorption refers to the maximum amount of dioctyl phthalate (DOP) absorbed by 100g of powder. In processing applications, the lower the oil absorption, the better. The lower the oil absorption, the less plasticizer it absorbs, and the lower the cost. Generally, the finer the powder particles, the greater the oil absorption.

5. Dummy specific gravity: Dummy specific gravity is usually also called bulk density or bulk density. In a certain sense, dummy specific gravity also reflects the fineness of the powder. It is considered in combination with D97, specific surface area and particle size distribution. An important indicator of body fineness.

6. Particle morphology: heavy calcium carbonate is usually divided into various particles such as polyhedron, flat body, cuboid, long rod, near sphere and irregular shape due to different processing equipment and different ore fields and crystal forms. shape. Polygonal and cuboid-shaped calcium carbonate has good fluidity in the processing of plastic products, and is easy to coat and cross-link with coupling agents, and the processing equipment wears less, but the mechanical properties of the product are relatively reduced; The surface area is relatively large. If surface treatment is performed, the coupling dose will increase, but the mechanical properties of the product are better.

7. Activation degree of surface-treated heavy calcium: Surface-treated heavy calcium is also called active heavy calcium. In order to improve the binding with the matrix material and improve its dispersibility, it is necessary to perform active treatment on it. For heavy calcium production enterprises, surface treatment of calcium carbonate is an important channel for deep processing of products, which can increase the added value of products and obtain better economic benefits. However, for activated calcium carbonate, not all downstream customers need to use activated calcium carbonate. Secondly, the active treatment of heavy calcium is usually realized by physical coating or chemical mechanical modification. The principle and process are different from the production process of light calcium. Carbonized anti-agglomeration treatment. In order to characterize the effect of heavy calcium activation treatment, we often use the index of activation degree to reflect its surface treatment effect.

8. Content of impurity elements: The content of impurity elements usually refers to the content of other elements in the ore except calcium carbonate. The main impurity elements are mainly silicon, magnesium, aluminum, iron, manganese, and other lead, cadmium, and chromium are classified as harmful heavy metal elements. Usually impurity elements exist in the form of oxides or in the form of carbonates, sulfates, silicates and other complex associated minerals, so when downstream customers are processing and applying, they should understand the form of their impurities. Presence will improve processing properties and product properties, while the presence of some impurities is detrimental to processed products.