Iron and steel scrap flow analysis in Japan

An effective utilization of scraps has been required for a establishing a sound material-cycle society. In order to understand the supply and demand system of the scrap at the present time, it is necessary to know the detail and precise scrap flow. For this purpose, the present study aims a material flow analysis for the iron and steel scraps. Since the iron and steel are the most typical base-materials for the society, it has been believed that we have enough amount of statistical information on their scrap markets. It is found by the present study, however, that the domestic circulation figure for iron and steel scrap was hard to be drawn due to mainly the discrepancy of the definition of each scrap category between the supplier and the user. Such discrepancy results in the following three major problems; (1) discontinuity of the scrap flow, (2) mismatching of the categories of supplied and used scraps, and (3) the lack of the data about un-collective scrap.