Immobilization of solid waste by vitrification using glass cullet

The vitrification is one of the methods used in the treatment of hazardous solid waste by converting them into leach-resistant materials. In the vitrification process glass is formed, in which hazardous substances, containing also heavy metals are permanently inertized. Among many approaches to the vitrification process one feasible way is the usage of glass cutlet as binding agent and a material that reduces the temperature of the whole process. The glass cutlet in this process acts as 'solvent' that permanently binds heavy metals inside the inorganic amorphous network of the silicate glass. In this study solid waste from the mound of the Chemical Plant in Tarnowskie Gory (actually in the liquidation) has been subjected to the vitrification process. For that particular solid waste the leaching of chemical substances by the water and 5% solution of nitric acid (V) has been determined. The vitrification of the solid waste has been performed in the laboratory scale of 100 at the following temperatures: 700 degrees C, 800 degrees C, 900 degrees C, 1000 degrees C and 1200 degrees C. Laboratory experiments have been performed for solid waste without additives and for blends of waste and the cutlet glass (10%/90% and 50%/50% respectively). The leaching of chemical substances from the vitrification products by the water and 5% solution of nitric acid (V) has been determined by weight. The contents of chlorides and sulphates in the resulted filtrates have also been determined. In the acid filtrates the contents of Cd, Cr, Cu, Mn, Ni, Ph and Zn have been determined using atomic absorption spectrometry (AAS). It has been stated that the process of vitrification of solid waste with the cutlet glass additive may be an effective method of inertization of toxic and hazardous waste inside the inorganic amorphous network of the silicate glass. This can reduce almost to the minimum their leaching effect on the environment. Moreover in the vitrification process considerable decrease of waste volume is achieved. The glass-ceramics, which is the product of that process, is not harmful for the environment so it can be use in the industrial sector.