This review outlines the geology and occurrence of kaolins in the world and the state of the art in processing high-quality kaolins. The physical and chemical characteristics of kaolin are also reviewed with respect to their use for specific applications in paper, ceramics and refractories, plastics, rubber, adhesives and paint industries.
KAOLIN: PROCESSING, PROPERTIES AND APPLICATIONS 93 to the USBM statistical production data (Table 1), the total US kaolin pro- duction stood at 9.89 million tons in 1988 which showed a 28% increase as compared to 7.95 million tons in 1984. Of this amount, 82% is produced in Georgia, 8% in South Carolina followed by 2.8% in Arkansas.
The physical and chemical characteristics of kaolin are also reviewed with respect to their use for specific applications in paper, ceramics and refractories, plastics, rubber, adhesives and paint industries. The market outlook for world kaolin is outlined with respect to product specifications, markets and
The flow properties of kaolin used for paper coating are very important. Both low-shear and high-shear viscosity measurements are made at 70-71 % solids. Low-viscosity kaolins are required for paper coating because the kaolin coating color must flow easily as it is applied to the paper surface, not leaving streaks or blotches, which can be .
A process flow diagram for kaolin mining and dry processing is presented in Figure 11.25-1, and Figure 11.25-2 illustrates the wet processing of kaolin. In the dry process, the material is crushed to the desired size, dried in rotary dryers, pulverized and air-floated to remove most of the coarse grit. Wet processing of kaolin begins with
The rheological properties of deflocculated suspensions of kaolin in water are im-portant in modern paper coating applications. The relation between the bulk physical properties of kaolin and rheology is complex. Viscosity at low rates of shear increases with increasing specific surface area of the kaolin. Viscosity at high rates of shear
In rubber, kaolin performs as a processing aide, giving the material dependable curing rates and increased strength with better resistance to tears and abrasions. In plastics, Kaolin helps improve impact and tensile strength, warp resistance, electrical and chemical resistance, and enhances smoothness and brightness.