Barite ore beneficiation The choice of barite ore dressing method is influenced by the type of ore, the nature of the ore, the size of the mine, and the use. The main mineral processing methods currently used are shown in Table 8. Generally, the residual ore is easy to be selected. Therefore, the re-election method is preferred; the sedimentary ore and the hydrothermal ore associated with sulfide ore, fluorite, etc., in addition to re-election, flotation method; barite flotation Anionic collectors generally used: fatty acid salts, petroleum sulfonates or sulfates.
Table 8 Main ore processing method of barite
| Mineral processing method | Principle of mineral processing | Application range |
| Hand selection | The difference in color, density, etc. between barite and associated minerals | Bulk barite |
| Re-election | Density difference between barite and associated minerals | Processes including washing, deliming, sieving, jigging, shaker, etc. are mostly used for residual ore |
| Flotation | Differences in surface physicochemical properties between barite and associated minerals | Commonly used in sedimentary barite ore and hydrothermal barite ore associated with sulfide ore, fluorite, etc. |
| magnetic separation | The magnetic iron oxide and barite difference minerals | Mainly used to remove iron oxide mineral impurities |
Barite ore beneficiation process
The beneficiation process of the residual barite ore is mainly selected by re-election method, that is, the barite concentrate is selected by jigging or other re-election method after washing, crushing and screening. . (1) The method of ore dressing of barite has hand selection, re-election, magnetic separation and flotation
Hand selection: After the original ore is mined, the simple manual selection is a common dressing method used by many rural miners. Some mines, due to high geological quality and stable quality, can meet the requirements of foreign trade export after hand selection. For example, the Pancun Mine in Xiangzhou, Guangxi, selects the rich ore by hand selection, the particle size requirement is 30-150mm, BaSO4>95%, and generally can be greater than 92%. The hand selection method is simple and easy, and does not require any equipment, but the productivity is low and the resources are wasted.
Barite ore beneficiation re-election: the ore is screened by crushing, crushed, graded and de-sludged. After jigging and beneficiation process, fine concentrate with good quality can be obtained, and the product grade can reach over 88%. The concentrate of Hengnan barite mine after gravity dressing can reach 92%. The local people wash the mine with the soil method, and each person can get 100kg of concentrate per day. The crusher is generally a jaw crusher or an impact crusher, and the fine crusher is generally a pair of roller crushers. Select heavy medium drum sorting machine, cone classifier, jig sorter or shaker, screw machine, etc. The barite inlay has a particle size greater than 2 mm, and can usually be sorted by a heavy medium and jigging. The maximum particle size for heavy media sorting is 50mm, and the maximum particle size for wet and dry jigging is about 20mm. The inlay size is less than 2 mm and can be sorted by a shaker or a spiral classifier. Before the selection, a hydrocyclone should be used to remove the mud to improve the sorting effect.
Magnetic separation: It is commonly used to select some iron-containing minerals such as siderite for use in barite raw materials that require very low iron-containing bismuth-based drugs.
Flotation: China's barite ore has more ore and less ore, and more than 80% of the deposits with proven reserves are associated with other minerals. For the sorting of ore and re-selected tailings with very fine grain size, flotation must be used. There are positive flotation flotation and reverse flotation two types of reverse flotation is usually to remove the alkali metal sulfide.
As a common salt mineral, barite is divided into two types according to the adsorption form. One is an anionic collector such as fatty acid alkyl sulfate or alkyl sulfonate, which is chemically adsorbed. Adsorbed on the surface of barite minerals and separated from others; the other is the use of cationic amine collectors to float barite in a physically adsorbed form. Amine collectors are low in efficiency and sensitive to slime, so anionic collectors are preferred. Usually, NaOH is added to the ball mill to adjust the pH value to 8 to 10. The water glass is added to the slurry as a conditioning agent, and the oleic acid collector is used for flotation under the condition of a solid concentration of 40% to 50%.
(2) Processing
1. Processing of high whiteness fine powder and ultrafine powder
The high whiteness finely pulverized barite powder is obtained by crushing, washing and whitening the barite ore. Holding the crystal structure of the mineral powder, widely used in coatings, rubber, plastics, paper, ceramics, etc., with a number of large and medium-coating plant which produce a variety of white powder paints instead of titanium, it is an excellent filler.
The process flow of the Wuhan University Management Cadre College of China University of Geosciences and the Coatings Industry Research Institute of the Ministry of Chemical Industry and the application of barite fine powder in the industrial production of Suizhou barite enterprises is shown in Figure 4.7.7.
Figure 4.7.7 Micro-powder industrial production process
Nclick="gotoRef(this)">[1]
The Suizhou barite deposit is a sedimentary layered deposit. The results of mineral chemical analysis are: BaSO4 94.78%, acid soluble 2.1%, Si 0.72%, organic carbon 0.56%, Ca 0.43%, Fe 0.12%, Al 0.10%, Mg 0.17%.
After a few crushed ore to obtain a fine micron-sized raw material, the fired roaster 2.5h, clinker becomes removed alkalis, acid washed beating, sulfuric acid was added in the reaction vessel was washed with water, the aluminum powder (acid-soluble, Bleaching, stirring reaction at boiling temperature for 2.5 h, to obtain a bleaching material, washing off the soluble salts with water, pressing and drying (170 ° C) to become a finished product. The technical performance of the product meets the quality specifications of IS03262 barite b grade.
The chemical reaction process of acid reduction in the reactor is as follows:
Acid solution: dissolves impurities and colored elements with sulfuric acid.
[Fe2O3]+3H2SO4=Fe2(SO4)3+3H2O
[MnO]+H2SO4=MnSO4+H2O
[NiO]+H2SO4=NiSO4+H2O
Bleaching: Adding aluminum powder, generating hydrogen, reducing Fe2+ to bleach.
2Al+3H2SO4=Al2(SO4)3+3H2
Fe2(SO4)3+H2=2FeSO4+H2SO4
Among the above physical and chemical processing methods, bleaching treatment and ultrafine grinding are two key technologies. The bleaching treatment is carried out by calcination (removing carbon) and pickling (removing impurities and colored elements). Therefore, it is necessary to know the calcination temperature and time, the acid concentration, the rinsing time, the amount of the reducing agent added, and the number of times of addition and release, etc., which should be reasonably selected. Ultra-fine grinding should use high-efficiency grinding machine and reasonable selection of relevant parameters.
The South-East Geological Brigade of Sichuan Province applied ultra-fine barite powder technology to process high-quality barite from a certain area in Sichuan, and produced BaSO4≥98%, Fe2O3≤0.05%, ZBD whiteness≥90%, fineness 98%+≤2μm Ultra-fine powder, and applied in the production of paper, rubber, paint and plastic, can completely replace the precipitated barium sulfate, and the basic performance of the product is better, and the industrial application prospect is more extensive.
2. Production of strontium salt products
Barite as raw materials to produce products in addition to the barium salt lithopone (lithopone), the main barium carbonate, barium chloride, barium hydroxide, barium nitrate, barium sulfate, barium titanate, barium molybdate, and some fine Chemicals.
(1) Lide powder (zinc antimony) Lide powder is white powder with an average particle size of 0.3-0.5 μm. It is insoluble in water, and does not work with hydrogen sulfide and lye. It decomposes in acid solution to release hydrogen sulfide. It will change color after long-term sun exposure, but it can still restore the original color when placed in a dark place. In addition to the production of raw materials lithopone barite, there are zinc oxide, sulfate, powder coal, which is the main chemical reaction:
ZnO+H2SO4=ZnSO4+H2O
BaSO4+2C=BaS+2CO2
ZnSO4+BaS=ZnS·BaSO4
(2) The main raw materials of barium carbonate are barite, limestone and coal. The process flow is: barite, pulverized coal → pulverization → roasting → heating steam leaching → clarification → carbonization → adding soda ash, steam desulfurization washing → filtration → drying → packaging.
(3) Barium chloride barium chloride is a white shiny monoclinic crystal which loses water when heated to 113 ° C and becomes a white powder. Soluble in water, solubility increases with increasing temperature. The aqueous solution has a bitter and salty taste and is toxic to humans, animals and insects.
The main raw materials are barite, coal, hydrochloric acid or chlorine gas, calcium chloride and the like. The preparation method includes a hydrochloric acid method, a calcium chloride method, and a chlorination method. The hydrochloric acid method is obtained by reacting barite with pulverized coal after calcination and reacting with hydrochloric acid. The calcium chloride method is also firstly reduced and calcined, and then obtained by leaching, desulfurization and the like. The chlorination method is a method in which a ruthenium sulfide solution is reacted with chlorine gas to obtain a ruthenium chloride solution, which is then treated.
(4) Barium hydroxide barium hydroxide is a white tetragonal system, easily soluble in hot water, and the solution is strongly alkaline. Anhydrous cesium hydroxide is a glossy white amorphous powder that is toxic.
In industrial production, the caustic soda method is mainly used, that is, it is obtained by reacting caustic soda with barium chloride solution, and evaporating, crystallizing and separating. Main chemical reactions:
BaCl2+2NaOH→Ba(OH)2+2NaCl
(5) Neodymium nitrate is a colorless or white cubic crystal, soluble in water and concentrated sulfuric acid. It decomposes at high temperature and decomposes into oxide when burned to emit green light and is toxic. It is mainly made of concentrated nitric acid and barium carbonate. It is also made of nitric acid (50%) and barium sulfide (such as Hengnan Chemical Pesticide Factory). The first grade product contains lanthanum nitrate ≥99.0%, and the second grade product ≥98.5%.
(6) Precipitated barium sulfate (barium sulfate) Barium sulfate is a white crystalline powder which is hardly soluble in water and is fused to fuming sulfuric acid and molten alkali. Easy and potassium permanganate, calcium carbonate, or alkali metal nitrate mixed crystal. Co-heating with carbon can be reduced to strontium sulfide.
The production method includes a barite refining method and a mirabilite- sulfurization method. The former is calcined with barite and coal powder, and then reacted with Na2SO4, and the latter is reacted with barium sulfide and thenardite, and subjected to pressure filtration and drying. Made separately.
Zinc Alloy Die Casting with Passivation have a good surface roughness, strength and elongation, Which are widely used in a variety of ornaments, such as furniture, accessories, door handle ,architectural decoration, bathroom accessories, lighting parts, toys, tie clips, belt buckles, various metal buckle and so on,they are required a good surface treatment performance.
Zinc Alloy Die Casting with Passivation have their own purposes, need to meet the performance requirements.
(1) mechanical properties, tensile strength, when the material fracture resistance;Elongation, brittleness and plasticity of the measure;Hardness is the resistance of the material surface is pressed into a hard object or friction caused by plastic deformation.
(2) state of the working environment: temperature, humidity, media contact with the workpiece and air tightness requirements.
(3) precision: accuracy and dimensional stability can be achieved.
Zinc Alloy Die Casting with Passivation
Zinc Casting Passivation, Zinc Passivation
Ningbo Zhenhai Xinxie Machinery Co.LTD , https://www.xinxie-diecasting.com