With the increasing depletion of high-quality, single-type barite ore, most of our country's barite ore currently has a low grade and is closely associated with other metal ores and non-metal ores, which directly affects its industrial use value. Barite weighting agent used as drilling mud generally requires a fineness of -0.056mm or more, density> 4.2g / cm, grade> 95%, soluble salt content 98%, CaO content <0.36%, and no magnesium oxide is allowed. , Lead and other harmful ingredients. Barite with different uses has different requirements for the purity, whiteness, and impurity content of the barite.

Physical purification: Guizhou barite physical purification methods mainly include: manual selection, re-selection, magnetic separation.

The main basis for manual selection is the difference in color and density between barite and associated minerals. After the raw ore is coarsely crushed, the barite mineral and the gangue mineral can be effectively dissociated, and the bulk barite can be selected by hand selection. For example, the Pancun mine in Xiangzhou, Guangxi, can be used to obtain rich ore with a particle size of 30 ~ 150mm and a BaSO4 content of> 92%. The manual selection method is simple and convenient, has low dependence on equipment and low cost, but requires high ore and low production efficiency, which causes great waste of resources.

Reselection is based on the difference in density between barite and associated minerals. The raw ore is crushed and ground to a certain grain size and enters into a re-sorting device for sorting to remove the gangue. The barium sulfate content in Hunan Hengnan barite ore mine after re-selection reaches above 92%. After the re-selection of the hand-selected tailings, a barium sulfate concentrate with a barium sulfate content of 84.50% can be obtained. Magnetic separation is a method that uses the magnetic difference between different ore to sort under the action of magnetic force. Magnetic separation is mainly used to remove some magnetic iron oxide minerals such as siderite, which is usually used in combination with gravity separation to reduce the iron content in the barite concentrate.

Flotation purification: With the continuous development and utilization of high-grade easy-to-select barite ore, there is an urgent need to increase the research and development of low-grade barite ore. Barite is often closely associated with minerals such as fluorite, calcite, and quartz, with low grades, fine embedded grains, and complex components, and it is difficult to effectively separate them by traditional reselection processes. Flotation can be adapted to various types of complex barite, so it has become the main method of barite selection at this stage. The collector is the key to determine whether the barite mineral can be effectively separated. The commonly used collectors can be divided into three types according to the type of adsorption: ① anion collector mainly based on chemical adsorption; cation mainly based on physical adsorption Collector; ③ amphoteric collector between the two. According to the separation process of barite and fluorite, it can be divided into two types: one is to suppress barite flotation fluorite; the other is to suppress fluorite flotation barite.

Purification by calcination: The calcination process of minerals is manifested by thermal dissociation into a mineral with a simpler composition or the crystalline form change of the mineral itself, from one solid phase pyrolysis to another solid phase and gas phase physical change process. Because the barite mineral is mixed with impurities such as Fe2O3, TiO2, and organic matter during the formation of the bed, these impurities will make the barite gray, green, and blue, which will affect the purity and whiteness of the barite and seriously reduce the weight The value of spar. Calcination can volatilize organic matter. Calcination and impurity removal are mainly suitable for removing impurities that can decompose or volatilize at high temperatures.

Leaching purification: Leaching purification is mainly used to remove carbon and colored impurities in barite. Their presence affects the whiteness and application prospect of barite concentrate. The main methods to remove these impurities are: acid leaching, oxidation-reduction, and organic acid complexation. The acid leaching method is to use an acid to react with an impurity metal or metal oxide in a mineral to generate a compound soluble in water or dilute acid. After washing and filtering, the soluble matter can be removed to achieve the purpose of purification. Lei Shaoming and others after leaching a concentrated barite mine in Hubei with concentrated sulfuric acid can increase the whiteness of barite powder from 84.10% to 88.60%. The oxidation-reduction method firstly adds an oxidant to dissolve the accompanying metal compounds in the mineral, and oxidizes the color-forming organic compounds in the barite, and then adds a reducing agent to reduce Fe to Fe, so that it can be dissolved, and the impurities can be whitened and the mineral level can be improved the goal of. Organic acid complexation method is to add organic acids such as EDTA, ascorbic acid, citric acid, oxalic acid, etc. in the iron removal process. Such acids can dissolve iron oxides and form complexes to achieve a good iron removal effect.

After the basic purification of barite, it can meet the requirements for the production of primary barium salts, but some fine and specialized products still cannot be produced, and they still need to rely on imports. Further exploration of the development of barite is needed.

Main uses: Barite ore is a non-renewable resource and is one of China's export advantage minerals. It is widely used as a weighting agent for oil and natural gas drilling muds. Its consumption in the fields of barium chemistry and fillers is also increasing year by year. China's barite resources are quite abundant, distributed in 21 provinces (regions) across the country, with total reserves of 360 million tons of ore, ranking first in the world. It is used medically as a contrast agent in the digestive system.

Circulating mud weighting agent cools the drill bit in the rotary drilling of petroleum drilling oil and gas wells, takes away the cutting debris, lubricates the drill rod, closes the hole wall, controls the oil and gas pressure, prevents the oil well from spouting, chemical production of barium carbonate, barium chloride, Various barium compounds such as barium sulfate, zinc barium white, barium hydroxide, barium oxide, etc. These barium compounds are widely used in reagents, catalysts, sugar refining, textiles, fire prevention, various fireworks, coagulants for synthetic rubber, plastics, insecticides Agent, steel surface hardening, fluorescent powder, fluorescent lamp, welding flux, grease additive, etc. Glass deoxidizers, clarifiers, and fluxes increase the optical stability, gloss, and strength of glass. Rubber, plastics, paint fillers, brighteners, weighting agents, building concrete aggregates, and paving materials weigh heavily on buried pipelines in swamp areas, instead of Lead plates are used for shielding of nuclear facilities, atomic energy plants, X-ray laboratories, etc., to extend the life of pavement.