Ceramic prods. made from clay mixt. - which includes spent fullers earth contg. oil, fat or wax, so external energy required for baking kiln can be reduced

摘要

Water and clay are mixed to form a plastic mass, part of the clay being replaced by active- or fullers- earth (I) contg. oil, fat, and/or wax. The mixt. may also contain lean clays, opening materials, and other conventional addns., and is moulded, dried, and baked to make prods., esp. coarse ceramics prods. Earth (I) pref. replaces 1-25, esp. 1-15% of the dry wt. of the clay. Earth (I) pref. contains 10-50%, esp. 15-35% oil, fat, and/or wax, based on its dry wt., and pref. has a calorific value of 4000-25,000, esp. 6000-20,000 kJ/kg. The process can be used e.g. in mfg. bricks, stoneware, clinker, refractories, etc. Earth (I) is used for the purification of mineral or vegetable oils, fats and waxes; the spent earth (I) thus has a high content of these materials, and can be used to reduce the energy consumption of baking kilns while also disposing of a material previously regarded as waste.