Preparation process of wet-process superfine modified calcium carbonate

Abstract

The invention discloses a preparation process of wet-process superfine modified calcium carbonate. The preparation process comprises the following steps: performing cleaning and screening, rough crushing, fine crushing, dry grinding and grading on calcite ores; collecting fine powder of 600 meshes and preparing slurry with water in such a manner that the solid content is 70%-80%; adding a modifier sodium stearate to the slurry for modification treatment and then performing wet grinding, and adding a grinding medium zirconium oxide microspheres and a dispersant sodium polyacrylate during grinding, wherein the volume ratio of the grinding medium to the slurry is 1: 1.5, and the dosage of the modifier is 0.6%-1.2% of the solid content; and putting the slurry obtained after the wet grinding through a vibrating screen, collecting the obtained wet-process superfine modified calcium carbonate slurry into a slurry barrel for flashing drying, collecting the finished product and packaging. The new preparation process is adopted; the wet grinding-modifying integrated technique and the flashing drying technique are adopted so that the production efficiency is high and the production cost is low; the product has the advantages of small particle size, low oil absorption value, high activity and the like; and the major product quality indices are at the international leading level.

Description

technical field [0001] The invention relates to the technical field of preparation and processing of ultrafine calcium carbonate nano powder, in particular to a preparation process of wet ultrafine modified calcium carbonate. Background technique [0002] Ultrafine calcium carbonate has special application properties due to its small particle size, uniform particle size and high surface activity. It is widely used in various industries such as coatings, plastics, papermaking, and inks. [0003] The traditional superfine calcium carbonate physical dry grinding production fineness is below 3000 mesh, which is difficult to refine and cannot meet the requirements of high-end industries. However, the nano-calcium carbonate product prepared by the calcination method is too fine, has high oil absorption value, insufficient rigidity, and high cost. In addition, the dry calcination process requires a large amount of coal, high production costs, large resource consumption, serious c...

AI Technical Summary

Problems solved by technology

[0003] The fineness of traditional superfine calcium carbonate physical dry milling is below 3000 mesh, which is difficult to refine and cannot meet the requirements of high-end industries.

However, the nano-calcium carbonate product prepared by the calcination method is too fine, has high oil absorption value, insufficient rigidity, and high cost.

In addition, the dry calcination process requires a large amount of coal, high production costs, large resource consumption, serious combustion exhaust gas pollution, high content of impurities such as coal ash, and low product purity. The produced heavy calcium carbonate can only be used in the coating industry

The existing process needs to use a lime shaft kiln to continue calcination, the production process cannot be operated continuously, and the production efficiency is low

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