Common Barite Beneficiation Processes and Equipment

Barite is a common barium mineral, its main component being barium sulfate (BaSO₄). It is an important industrial mineral raw material for the production of barium and barium compounds. Taking barite deposits in my country as an example, they are mainly divided into four types: sedimentary deposits, volcanic sedimentary deposits, hydrothermal deposits, and residual deposits. Based on ore type, raw ore properties, mine scale, and intended use, commonly used barite beneficiation methods include hand sorting, gravity separation, flotation, magnetic separation, and combined processes. Generally, residual barite ore is easier to beneficiate and gravity separation is preferred; sedimentary barite ore and hydrothermal barite ore associated with sulfide minerals and fluorite require flotation in addition to gravity separation.

Below, we will explain each barite beneficiation process and the barite beneficiation equipment used in each process.

I. Barite Hand-Separation Method

After the raw ore is mined, simple manual hand-separation is a common beneficiation method in many small mines. Because some mines have high geological grades and stable quality, qualified barite products can be selected by hand-separation based on the differences in color, density, etc., between barite and associated minerals. For rich-grade barite ore selected by hand-separation, the particle size requirement is 30-150mm, BaSO₄>95%, generally greater than 92%. Overall, hand-separation is simple and easy to implement, requiring no barite beneficiation equipment, and is suitable for small-scale beneficiation. However, it has low productivity, requires high ore grade, and results in significant resource waste.

II. Barite Gravity Separation Method:

The barite gravity separation method mainly relies on the density difference between barite and associated minerals for separation. It includes processes such as washing, screening, desliming, jigging, and shaking tables, and is mostly used for processing residual barite ores. After washing, screening, crushing, and desliming, the raw ore is further processed by barite beneficiation equipment such as jigging and shaking tables to obtain high-quality barite concentrate with a product grade of over 88%. Jaw crushers or impact crushers are generally used in the crushing stage, while double-roll crushers are typically used for fine crushing. The beneficiation stage employs heavy media rotary separators, cone classifiers, jigging separators, or shaking tables. When the barite particle size is greater than 2mm, heavy media separation or jigging is usually used, but the upper limit for heavy media separation is 50mm, while the upper limit for wet and dry jigging is approximately 20mm. When the barite particle size is less than 2mm, shaking tables can be used for separation, but a hydrocyclone must be used to remove mud before the finer processing to improve the separation effect.

III. Barite Flotation

Barite has a relatively high specific gravity, 4-4.6, and good floatability. Barite flotation primarily relies on the differences in surface physicochemical properties between barite and associated minerals for separation. It is commonly used for sedimentary barite deposits and hydrothermal barite ores associated with sulfide minerals and fluorite. Taking China as an example, barite deposits are predominantly low-grade, with over 80% of proven reserves associated with other minerals. Flotation is essential for separating finely sized ores and for gravity separation tailings. Common barite flotation processes include direct flotation and reverse flotation, with reverse flotation aimed at removing alkali metal sulfides. As a common salt mineral, barite flotation can be categorized into two types based on adsorption methods: one uses anionic collectors such as fatty acid alkyl sulfates and alkyl sulfonates for chemical adsorption on the barite surface, thus separating it from other associated minerals; the other uses cationic amine collectors for physical adsorption. Amine collectors have low collection efficiency and are extremely sensitive to the slime; therefore, anionic collectors are more ideal. Typically, NaOH is added to the ball mill to adjust the pH to 8-10, and water glass is added to the slurry as a modifier. Barite flotation is then carried out using oleic acid collectors at a solids concentration of 40%-50%.

IV. Barite Magnetic Separation

Barite magnetic separation mainly relies on the difference in surface magnetic properties between barite and iron oxide minerals. It is commonly used to separate barite from iron-bearing minerals such as siderite. Magnetic separation is often used in conjunction with gravity separation to produce barite feedstock for use with barium-based reagents requiring very low iron content.

V. Combined Barite Process

Barite deposits associated with sulfide minerals often employ a combined gravity separation-flotation process. Taking barite-quartz-calcite type ore beneficiation as an example, in the combined flotation-gravity separation process, sodium silicate and a collector are added to the flotation cell to remove quartz impurities, resulting in a mixed ore of barite and calcite. Then, based on the density difference between calcite and other gangue minerals and barite, gravity separation equipment such as jigs and shaking tables are used for gravity separation to finally obtain barite concentrate. Early barite mines were mostly high-grade ores, typically using low-cost, low-tech hand-separation or gravity separation methods. However, with the decreasing grade and increasing complexity of barite ore properties, magnetic separation, flotation, and combined beneficiation methods are increasingly widely used in barite ore beneficiation. It is recommended that mine owners develop scientific and reasonable flotation processes based on beneficiation test reports to avoid unnecessary economic losses.