The potential use of cement-asbestos waste in the ceramic masses destined for sintered wall clay brick manufacture

Asbestos fibers are considered to be carcinogenic and to cause cancer, thus elimination of asbestos-containing materials from the environment is necessary. Currently, asbestos materials are stored in special landfills designed for hazardous wastes. However, this procedure is not a final solution to the problem and an alternative might be thermal recycling. This paper reports the results of a study on using asbestos-cement slates as an additive to ceramic masses that are typical in the manufacture of sintered clinker wall bricks. Green compacts containing various amounts (0-10 wt%) of asbestos-cement wastes were sintered at temperatures of 1100-1200 °C. Subsequently, ceramic product properties such as water absorption, open porosity, apparent density, compressive strength and freeze resistance were determined. The preliminary results of the study indicate that asbestos-containing materials can be used as one of the raw materials in the manufacture of clinker ceramic material, and that the origin of the asbestos-cement used does not have a significant influence on the basic properties of sintered clinker wall bricks. Main ceramic properties, such as water absorption, compressive strength and freeze resistance, comply with national standards and requirements for construction and road clinker ceramic.