著者
醍醐 市朗 五十嵐 佑馬 松野 泰也 足立 芳寛
出版者
社団法人日本鉄鋼協会
雑誌
鐵と鋼 : 日本鐡鋼協會々誌 (ISSN:00211575)
巻号頁・発行日
vol.93, no.1, pp.66-70, 2007-01-01
被引用文献数
2 17

During the last two decades, the total material input in Japan has been about 2 billion tons, and approximately 50%, i.e., about 1 billion tons has accumulated as the net addition to stock in the form of buildings, social infrastructure, and various kinds of products. The amount of the net addition to stock is calculated annually from the differential between the input and the output. Therefore, the contents of the accumulated stock are unknown. It is said that these unknown contents include material that has already been discarded as invisible waste. In this study, dynamic material flow analysis was conducted to quantify the amount of stock that is not associated with social activities and cannot possibly be collected as scrap in the future. First, we defined some terms: in-use stock, hibernating stock, and overall stock. Hibernating stock comprises the steel used for the constructional material of land fill site, the steel dissipated by corrosion and erosion, etc. Furthermore, we defined the system boundary to account for the steel stock and constructed equations to calculate the three types of stock. To calculate the amount of in-use stock, a dynamic model-the population balance model-was adopted. The amounts of in-use stock and hibernating stock in Japan from 1980 to 2000 were calculated. The result shows that 0.96 billion tons of the in-use stock is included in the 1.22 billion tons of overall stock in the year 2000.
著者
玉城 わかな 五十嵐 佑馬 藤巻 大輔 林 誠一 友田 陽 松野 泰也 長坂 徹也
出版者
The Iron and Steel Institute of Japan
雑誌
鉄と鋼 (ISSN:00211575)
巻号頁・発行日
vol.92, no.5, pp.340-345, 2006-05-01 (Released:2009-06-19)
参考文献数
20
被引用文献数
6 6

1.91 milliont of steel scrap was exported from Japan to Korea in 2003, which accounted for more than 30% of the total steel scrap exported to other countries from Japan. Change in steel scrap demand in Korea in the future will make a great influence on the amount of Japan's steel scrap domestic consumption and export. In this work, quantitative data about the steel production, steel scrap demand and consumption during 1977-2003 in Korea were collected to analyze the amounts of inhouse, industrial and obsolete scrap generation, and total steel accumulation in Korea. Then, the steel scrap demand in Korea in the future was estimated. The total accumulation of steel in Korea was estimated as 380 million t in 2003 and 548 million t in 2010, respectively. The amount of obsolete scrap generation in Korea was 7.1 million t in 1996 and 9.0 million t in 2003, which was about 3.0% and 2.4% of the total steel accumulation in each year. Supposing that the amount of crude steel production, scrap consumption percentages in B.O.F and E.A.F will be stable, the obsolete scrap generation in Korea in 2010 were estimated as 13-17 million t. This significant increase in obsolete scrap generation in Korea could exceed the current amount of the scrap import. So, self-sufficiency of steel scrap could be achieved in around 2010 in Korea.