Production and utilisation of iron and steelmaking slag in Japan and the application of steelmaking slag for the recovery of paddy fields damaged by Tsunami

In Japan, about 40 million tonnes of slag is generated annually during the iron and steelmaking process. This large amount of byproduct warrants investigation on its disposal. In this study, the production, chemical characteristics, and use of iron and steel slag in Japan, especially converter slag, have been reviewed. Then, the necessity for sodium removal and nutrient supply for the recovery of the paddy fields damaged by the Tsunami, which resulted from the great east Japan earthquake, has been explained. Since converter slag can serve the above two requirements simultaneously, owing to its chemical properties, investigations on efficient utilisation of converter slag have been carried out. With the perspective of both agriculture and engineering science, the positive effects of converter slag on desalting, pH improvement, and supply of nutrients such as silicon have been found.