The effects of borax petahydrate alkaline on anhydrous borax melting furnace refractory bricks

In the production process of anhydrous borax, the refractory materials used in melting furnaces both affect the product quality and constitute one of the biggest cost items. This thesis work consists of 2 (two) stages. In the first stage, the corrosion resistance of fused cast AZS (Al2O3-ZrO2-SiO2) refractory bricks and andalusite based high alumina refractory bricks used in existing anhydrous borax melting furnaces were comparatively investigated depending on chemical composition, temperature and time. AZS TYPE-1, AZS TYPE-2, AZS TYPE-3 and andaluzite based high alumina refractory bricks were subjected to corrosion attack tests of molten borax pentahydrate at 850 °C 24 hours, 850 °C 48 hours and 950 °C 24 hours. At the end of the experiment, the wear amount of the samples was measured and SEM analyzes were made and comparatively examined. As a result of the experiments, it has been seen that the refractory providing the lowest corrosion resistance is the andaluzite-based high alumina brick, and the amount of resistance to corrosion increases as the amount of zirconia in the melt cast AZS refractories increases. The purpose of the second stage experimental studies is to select refractory materials that can be an alternative to the existing refractory materials used in anhydrous borax melting furnaces, provide an advantage in terms of cost, and not affect the product quality. In this context, the interactions of graphite, chrome magnesite, fused chrome, mag-carbon and silicon carbide refractories with borax pentahydrate molten at 850 °C and 12 hours were investigated. It was concluded that these refractory bricks, which were studied within the scope of alternative refractory selection studies, are not suitable for use in anhydrous borax melting furnaces. Keywords: Refractory, Anhydrous Borax, Borax Pentahydrate, Corrosion