At present, there are some environmental problems such as an increase in the domestic waste and a shortage of landfill site in Japan. Especially, the amount of paper products (newspaper, photocopy paper, corrugated board, weekly magazine, gravure magazine, catalog, etc.) accounting for more than50% of all domestic waste has been increasing. Therefore, the reduction of its incineration ash becomes a pressing task for using the landfill site as long as possible. In this study, the effect of melting treatment on the reduction of paper products was investigated, and the amounts of chlorine in combustion gas and in residual ash generated from each paper product were evaluated.
The melting treatment was found to reduce effectively the amount of paper products, and therefore to be effective for prolonging period of landfill site in Japan. The chemical composition of the slag prepared by melting paper products was mainly composed of several compounds in the SiO2-Al2O3-CaO system, and the slag was suitable for preparing various glasses. Furthermore, the melting temperature decreased in increasing amounts of glass cullet that was mixed with combustion ash. The amounts of Pb and Sb eluted from the molten slag in pure water, salt solution (3.5 wt%) and acid solution (pH 3) were much lower than those from the combustion ash. In addition, the chloride gas and chloride compounds in residual ash generated from the combustion of paper products were scarcely detected. These results suggested that the amount of toxic chlorine emitted by melting paper products is extremely small.
