Diatomite is a biogenic siliceous sedimentary rock, which is mainly distributed in China, the United States, Denmark, France, the Soviet Union, Romania and other countries. Its chemical composition is mainly SiO2, which can be expressed by SiO2 · nH2O, and its mineral composition is Opal and its variants. China's Diatomite reserves are 320 million tons, with prospective reserves of more than 2 billion tons. It is mainly concentrated in East China and Northeast China, of which Jilin, Zhejiang, Yunnan, Shandong, Sichuan and other provinces have done more work. Although it is widely distributed, high-quality soil is only concentrated in Changbai and Yunnan regions of Jilin Province. Most of other deposits are grade 3 ~ 4 soil. Due to the high content of impurities, It cannot be directly processed and utilized.

Chinese Synonyms: diatomite filter aid, diatomite filler, diatomite thermal insulation material, diatomite soil conditioner, diatomite feed additive

Chemical composition: the chemical composition of diatomite is mainly SiO2, containing a small amount of Al2O3, Fe2O3, Cao, MgO and organic matter

Physical properties: the density of diatomite is 1.9-2.3g/cm, the bulk density is 0.34-0.65g/cm, the specific surface area is 40-65m / g, the pore volume is 0.45-0.98m, the water absorption is 2-4 times of its own volume, and the melting point is 1650c-1750c. The special porous structure can be observed under the electron microscope.

Raw ore properties:

Diatomite is a biogenic siliceous sedimentary rock, which is mainly composed of ancient diatom remains. Its chemical composition is mainly SiO2, containing a small amount of Al2O3, Fe2O3, Cao, MgO, K2O, Na2O, P2O5 and organic matter. SiO2 usually accounts for more than 80%, up to 94%. The iron oxide content of high-quality diatomite is generally 1 ~ 1.5%, and the alumina content is 3 ~ 6%. The mineral composition of diatomite is mainly Opal and its variants, followed by clay minerals - hydromica, kaolinite and mineral debris. Mineral fragments include quartz, feldspar, biotite and organic matter. The content of organic matter ranges from trace to more than 30%. The color of diatomite is white, grayish white, gray and light grayish brown, with fine, loose, light, porous, strong water absorption and permeability. Diatoms in diatomite have many different shapes, such as disc, needle, tube, feather and so on. The loose density is 0.3-0.5g/cm3, the Mohs hardness is 1-1.5 (diatom bone particles are 4.5-5mm), the porosity is 80-90%, and it can absorb water 1.5-4 times its own weight. It is a poor conductor of heat, electricity and sound, with a melting point of 1650-1750 ° C and high chemical stability. It is insoluble in any strong acid except hydrofluoric acid, but can be dissolved in strong alkali solution. Most of the silica in diatomite is amorphous, and the content of soluble silicic acid in alkali is 50 ~ 80%. Amorphous SiO2 becomes crystalline when heated to 800 ~ 1000 ° C, and the soluble silicic acid in alkali can be reduced to 20 ~ 30%.

Application scope:

The application scope of industrial filler of diatomite is agricultural and pharmaceutical industry: wettable powder, dryland herbicide, paddy field herbicide and various biological pesticides. Advantages of using diatomite: neutral pH value, non-toxic, good suspension performance, strong adsorption performance, light bulk weight, 115% oil absorption rate, fineness between 325 mesh and 500 mesh, good mixing uniformity, no blocking of agricultural machinery pipeline during use, moisturizing in soil, loosening soil, prolonging efficacy and fertilizer effect time, and promoting crop growth. Compound fertilizer industry: compound fertilizer for various crops such as fruits, trees, vegetables, flowers and plants. Advantages of diatomite: strong adsorption performance, light bulk density, uniform fineness, neutral pH value, non-toxic and good mixing uniformity. Diatomite can become a high-efficiency fertilizer, promote crop growth and improve soil. Rubber industry: fillers in various rubber products such as vehicle tires, rubber pipes, V-belts, rubber rolling, conveyor belts, automobile footmats, etc. The advantage of diatomite is that it can obviously enhance the rigidity and strength of the products, and the settlement volume is up to 95%. It can also improve the chemical properties of the products such as heat resistance, wear resistance, heat preservation and anti-aging. Building thermal insulation industry: roof thermal insulation layer, thermal insulation brick, calcium silicate thermal insulation material, porous coal cake furnace, sound insulation and fireproof decorative board and other thermal insulation, heat insulation and sound insulation building materials, wall sound insulation decorative board, floor tile, ceramic products, etc; Advantages of using diatomite: diatomite should be used as an additive in cement. Adding 5% diatomite in the production of cement can improve the strength ZMP, and SiO2 in cement can become active, which can be used as emergency cement. Plastic industry: living plastic products, building plastic products, agricultural plastics, window and door plastics, various plastic pipes, other light and heavy industrial plastic products. The application of diatomite has the advantages of excellent extensibility, high impact strength, tensile strength, tear strength, light and soft, good internal abrasion, good compression strength and so on. Paper industry: office paper, industrial paper and other paper; Advantages of using diatomite: light and soft constitution, fineness in the range of 120 mesh to 1200 mesh. The addition of diatomite can make the paper smooth, light weight, good strength, reduce expansion caused by humidity change, adjust the combustion rate in cigarette paper without any toxic and side effects, improve the clarity of filtrate in filter paper and accelerate the filtration speed. Paint and coating industry: furniture, office paint, architectural paint, machinery, home appliance paint, mimeograph ink, asphalt meter, automobile paint and other paint and coating fillers; Advantages of diatomite: neutral pH value, non-toxic, fineness of 120 mesh to 1200 mesh, light and soft constitution. It is a high-quality filler in paint. Feed industry: additives for pigs, chickens, ducks, geese, fish, birds, aquatic products and other feeds. Advantages of using diatomite: pH value is neutral and non-toxic. Diatomite mineral powder has unique pore structure, light and soft weight, large porosity and strong adsorption performance. It forms light and soft color. It can be evenly dispersed in feed and bonded and mixed with feed particles, which is not easy to separate and precipitate. It can promote digestion after livestock and poultry eat, and can adsorb and excrete bacteria in gastrointestinal tract of livestock and poultry, Enhance physique, play the role of strengthening tendons and bones. Aquatic products are put into the fish pond, the water quality becomes clear, the air permeability is good, and the survival rate of aquatic products is improved. Polishing and friction industry: polishing of brake pads, mechanical steel plates, wood furniture, glass, etc. in vehicles; Advantages of using diatomite: strong lubrication performance. Leather and artificial leather industry: artificial leather products and other leather. Advantages of diatomite: strong sunscreen, soft and light constitution, high-quality filler that can eliminate leather pollution, balloon products: light capacity, neutral pH value, non-toxic, light, soft and smooth powder, good strength performance, sunscreen and high temperature resistance. Diatomite is a high-quality filler used in mosquito repellent incense. Diatomite can adsorb drugs and improve the effect of killing mosquitoes. Advantages of using diatomite: pH value is neutral, non-toxic, light volume weight of 0.35, fine powder, good mixing uniformity, sio267%, and promoting human health. With the improvement of people's living standards and the enhancement of health awareness, non-toxic smokeless mosquito repellent incense must be applied. Diatomite can support combustion, smokeless and non-toxic, which is deeply welcomed by users. Coating, paint, sewage treatment and other industries

Main advantages:

Diatomite coating additive products have the characteristics of large porosity, strong absorption, stable chemical properties, wear resistance and heat resistance. They can provide excellent surface properties, compatibilization, thickening and adhesion for coatings. Because of its large pore volume, it can shorten the drying time of the film. It can also reduce the amount of resin and reduce the cost. The product is considered to be a high-efficiency matting powder product for coatings with good cost performance. It has been used as a designated product by many large coating manufacturers in the world. It is widely used in a variety of coating systems such as latex paint, interior and exterior wall paint, alkyd resin paint and polyester paint, especially in the production of architectural coatings. In the application of coatings and paints, it can evenly control the surface gloss of the film, increase the wear resistance and scratch resistance of the film, dehumidify and deodorize, purify the air, and has the characteristics of good sound insulation, waterproof, heat insulation and permeability.

Classification and naming:

Diatomite is a kind of siliceous rock, which can be divided into two categories according to its genesis: biological or biochemical origin - diatomite, plate diatomite, protein soil, radiolarian rock and sponge rock.

Abiogenic (chemical, volcanic, secondary) - Jasper, chert, sillimanite, quartzite.

The main associated minerals in diatomite are clay minerals and carbonaceous (organic matter). When the content of these minerals reaches more than 50%, they belong to clay rock and carbonaceous shale, which is named diatom x rock. When the content of these minerals is less than 50%, they belong to diatomite, which is named x x diatomite.

The main mineral composition of diatomite is Opal and contains clay (kaolinite, water parent rock and a small amount of Jiaoling stone), carbonaceous (organic matter), iron (limonite, hematite and pyrite), carbonate minerals (calcite, dolomite and a small amount of siderite), quartz, muscovite, glauconite and feldspar.

1. Opal si02nh20 2, clay mineral, carbonaceous

Clay minerals and carbonaceous are the main associated minerals in diatomite. Clay minerals are distributed around diatom particles in micro scale shape. When the content of clay minerals is the main component, it plays the role of cementing diatom. Carbonaceous matter is associated with diatomite in point, block or layer. Carbonaceous matter is peat and lignite with low metamorphic degree and still retaining plant structure.

Diatomite decoration materials in Japan's building materials market mainly fall into three categories: one is natural dry products containing impure substances, which are cheap. The other is ordinary kiln fired products. It is first made of diatomite into plates and bricks of various shapes, and then fired at a high temperature of 800 ℃. It is a bit like ceramic tile, and the price is general. The third category is kiln fired products with various additives. This kind of high-grade products added with special materials use high-quality diatomite and add additives such as salt, soda ash or photocatalyst to remove impure organic matter, carbon and other substances in a kiln with a high temperature of about 1100 ℃, and burn them into various high-grade and gorgeous diatomite room decoration materials. Diatomite decoration materials sold in the Japanese market mainly include wall materials (plates), flooring materials, sanitary ware, ceiling materials, etc. In the Tokyo building materials market, the price of ordinary diatomite wall materials is more than 2000 yen per square meter (about 110 yen per dollar). Some companies have also developed a diatomite waterborne coating, which can further strengthen the environmental protection effect of diatomite decoration materials.

Diatomite is a kind of rock with biological structure. It is mainly composed of 80 ~ 90% and some more than 90% diatom shells. Diatom is the main consumer of silicon oxide in seawater and lake water, forming diatom ooze. Diatomite is formed in the petrochemical stage during diagenesis.

Diatom shell is composed of opal. In the process of growth and reproduction, diatom absorbs colloidal silica in water and gradually transforms into opal.

The more diatom content and less impurities in diatomite, the whiter the color and the lighter the quality. The specific gravity is generally 0.4-0.9. Because the diatom has many shell holes, the diatomite has a porous structure. The porosity of diatomite reaches 90-92%, with strong water absorption and sticky tongue. Because the diatom particles are small, the diatomite is fine and smooth. Diatomite is insoluble in acid (HCl, H2SO4, HNO3), but soluble in HF and KOH.