The demand for high grade materials as well as market availability and pricing policy of suppliers are reasons for the rise on raw-material prices. With the exception of clay, these materials are scarce. The production of the synthetic raw-materialsrequires plenty of energy and hence is expensive. Use of recycled raw-materials is alternative option to substitute the more and more expensive and scarce raw-materials.
The steel industry uses 70% of all refractory products. When they are spent, they can be a valuable source of raw-materials. Therefore it is necessary to sort the waste and recycle it.
The refractory breaks should be collected in dependence of origin and sorting and clearing should always ensure an exactly graded product of the further treatment as raw-material. Colour, lustre, grain-shape, brick-size and analyses in the reworking phase are differentiation criteria. Depending on customer’s wishes, further reworking is made by breaking, drying, grinding, screening, blending and packing. Portion of the disturbing magnetic matters (iron, slag) can be reduced by magnetic separation.
Most of the materials reworked are bricks and fused materials and price level of the different processed materials is in the range of 60-100% of the respective primary raw-materials. Depending on the grain-shape, porosity, density, impurities, phases and coking, the % substitution of the primary raw-materials can be decided.