The chemical composition of dolomite is CaMg(CO3)2, and the crystal is a carbonate mineral of the trigonal crystal system. The crystal structure of dolomite is similar to that of calcite. The crystal form is rhombohedron, and the crystal face is often bent into a saddle shape. The double crystals are common, mostly in block and granular aggregates. Pure dolomite is white, because it contains other elements and impurities, sometimes it is gray-green, gray-yellow, pink and other colors, and the glass is shiny. The three groups of rhombohedrons are completely cleavage and brittle. Mohs hardness is 3.5-4, specific gravity is 2.8-2.9. Mineral powder reacts slowly in cold dilute hydrochloric acid.
Dolomite is sorted, crushed, and ground into dolomite powder from 325 to 2000 meshes. With the large-scale and application requirements of the dolomite powder industry, the traditional small-scale and multi-equipment extensive processing mode can no longer meet the market demand. Therefore, the use of new It is imperative to improve the processing scale and technical level of the company’s powder technology and equipment. The LUM series of ultra-fine vertical mills are the crushing, drying, grading, transportation, secondary powder selection and finished products developed by Kolyric for many years. A comprehensive mill with six functions such as packaging can effectively increase the added value of dolomite products. The output of the same product LUM series ultra-fine vertical mill can be increased by 30%.
The dolomite powder processed by the Shanghai Zenith ultrafine vertical mill can be added to natural rubber and synthetic rubber. Its rubber performance is basically the same as that of adding light calcium powder, but the cost is lower than that of light calcium powder. Dolomite is used to produce rubber general-purpose calcium-magnesium powder. As a new type of additive and coloring agent, it can partially or completely replace light calcium powder. The surface-modified dolomite powder can greatly increase the reinforcing performance of rubber products. Modified dolomite powder is to coat the surface of dolomite powder with a surface modifier, and then use it as a filler. Commonly used surface modifiers include stearic acid or stearate, titanate, zirconium aluminate, and mixed silane coupling agents. The purpose of modification is to change the surface alkalinity of dolomite powder, overcome the bonding performance between filler and rubber, reduce shrinkage and internal stress, prevent crack propagation, and improve the processing performance of product strength.