Chapter 1. Kaolin and Ball Clay Processing for Ceramic Utilization

Summary

The purpose of processing is to remove and/or reduce impurities and to enhance physical properties. In order to determine the best method to remove impurities, the impurities must be identified and their particle size determined. Quartz, mica, iron minerals, titanium minerals, and carbonaceous compounds are the major impurities. Physical properties that can be altered and enhanced are particle size, shape, and distribution; surface area; color; rheology; plasticity; modulus of rupture; shrinkage; fired color; casting rate; and suspension. Some of the processes that are used to reduce impurity levels and enhance physical properties are screening, classification by centrifuge, high-intensity magnetic separation, blending, flotation, selective flocculation, grinding (wet and dry), calcination, and dispersion. The amount and type of processing are limited by cost.