UTILIZING OF BORAX SOLID WASTES IN ROOF TILE AND BRICK BODIES Guray Kaya, Bekir Karasu and Erkul Karacaoglu Anadolu University, Department of Materials Science and Engineering, Iki Eylul Campus, 26555 Eskisehir, Turkiye Keywords: Borax solid wastes, Utilizing, Roof tile and brick bodies, Recycling, Characterization. Abstract Boron minerals are widely employed in various fields such as ceramic, glass, cement, metallurgy, etc. Although boron deposits of the world are limited, the production level of boron-based products is continuously increased. Turkiye possesses approximately 73 % of total world boron resources. Etibor Kirka Borax Company of Turkiye produces tincal concentrates and borax pentahydrates. During such productions considerable amounts of concentration and derivation wastes appear. Having considered the increased rate of production it is quite obvious that the level of relevant wastes will also be raised. With this study it was aimed to utilize these wastes in roof tile and brick bodies and to convert them into a form environmentally and human friendly. Newly produced products were undergone to several standard tests for the determination of their shrinkage, water absorption, strength values and coloring parameters. Additionally, micro structural studies were conducted. Introduction Boron is regarded as an important candidate for the source of energy in the new millennium since the fossil fuels are coming to an end and also affecting environment detrimentally [1]. Turkiye has the largest known reserves of boron minerals in the world [2]. The most important boron ores in Turkiye are colemanite, ulexite and tincal [3-4]. The major mining method is open pit mining, underground mining being practiced in two mines. Run-of mine ores are enriched by selective crushing, attrition scrubbing and classifying. Concentrates are either directly marketed or treated to produce refined products, namely decahydrate, pentahydrate, perborate and boric acid [2]. Etibor Kirka Borax Company, which was founded in Kirka-Eskisehir, is known to own the biggest borax mines in the world. In there, 800.000 t/yr of concentrated tincal, 160.000 t/yr of borax pentahydrate, 60.000 t/yr of anhydrate borax and 17.000 t/yr of borax decahydrate are produced from tinkal [5]. As much as 400.000 t/yr wastes such as borax slime, lineal, concentrator and derivative waste are discharged during operations. The wastes are mainly composed of clay minerals; montmorillonite, vermiculite, illite, chlorite and contain up to 10-20 % B 2 O 3 . Presently, these wastes are collected in tailing dams. Although boron is a known micro nutrient, higher concentrations are reported to be deleterious for plants [7] and materials with high boron concentration should be considered as a pollutant. In order to alleviate the pollution problem at borax plants, several attempts have been made to handle or use these wastes in different ways [8-15]. In the present study, Etibor Kirka Borax Company’s concentrator and derivative wastes were evaluated in roof tile and brick bodies at different ratios up to 10 %. It was thought that utilizing these wastes would not only remedy the environmental problems associated with them but also might improve the quality of the relevant bodies. 535 Sohn International Symposium ADVANCED PROCESSING OF METALS AND MATERIALS VOLUME 1 - THERMO AND PHYSICOCHEMICAL PRINCIPLES: NON-FERROUS HIGH-TEMPERATURE PROCESSING Edited by F. Kongoli and R.G. Reddy TMS (The Minerals, Metals & Materials Society), 2006