Ore Beneficiation Plants
Kaolin Ore Beneficiation
The most widespread industrial use of kaolin is as a filler and coating material in paper production. It is also used in ceramics (porcelain, refractories), the rubber industry (for strength and abrasion resistance), paints and inks (as filler/extender or in place of titanium-based pigments), as well as in cosmetics, soap, toothpaste, pharmaceuticals (adsorbent or carrier), fertilizers, detergents and catalysts.
Kaolinite ore contains not only the targeted aluminium silicate minerals but also unwanted impurity minerals such as quartz, iron oxides and titanium dioxide (rutile). Therefore, to obtain a high-purity product suitable for industrial use, the raw ore from the mine must undergo various beneficiation operations. These typically include crushing, grinding, screening, classification, magnetic separation, packaging and loading. However, the process flow must be tailored to the mineralogical and chemical properties of the ore and the target product specifications. As BAS, we deliver the right process flow, engineering and correct magnetic separation steps for the ore as a turn-key scope.
Kaolinite (Al₂Si₂O₅(OH)₄) is the main component of kaolin and can occur with other kaolin minerals such as dickite, nacrite and halloysite. Ore origin and the impurities it contains directly affect colour, brightness and refractoriness, which determine its commercial value. In particular, iron oxide and hydroxide minerals such as hematite, goethite and lepidocrocite — even at levels as low as 0.4% — can give the product undesired colours ranging from red to yellow. This adversely affects marketability and reduces value. Effective removal of these iron compounds is therefore a critical step in producing high-quality kaolin.
Magnetic separation is an effective and widely preferred method for removing iron-bearing impurities from kaolin. This method is preferred at industrial scale for its high separation efficiency, low energy consumption, low operating costs and ease of application.