Dynamic material flow analysis of nickel and chromium associated with steel materials by using matrace

¹ Department of Metallurgy, Materials Science and Materials Processing, Graduate School of Engineering, Tohoku University, Miyagi, Japan
² Department of Chemical Engineering, Graduate School of Engineering, Tohoku University, Miyagi, Japan
³ Department of Environmental Studies for Advanced Society, Graduate School of Environmental Studies, Tohoku University, Miyagi, Japan
⁴ Center for Material Cycles and Waste Management Research, National Institute for Environmental Studies, Ibaraki, Japan
⁵ Faculty of Political Science and Economics, Waseda University, Tokyo, Japan

^a Corresponding author: kentaro.takeyama.t2@dc.tohoku.ac.jp

Received: 19 September 2016
Accepted: 20 February 2017

Abstract

A stable supply of alloy elements is essential for steel production, and strategic management of alloy elements is important not only for the steel industry, but for every manufacturing industry However, in the current recycling system, steel scrap is mainly used as a source of iron. When scrap contains large amounts of alloy elements, they were regarded simply as impurities and dissipated Material flow analyses are useful tools for investigating material cycles and reveal important information about the structural problems including dissipation or inefficient usage of target material In this study, dynamic material flow analysis of alloy elements associated with steel materials, especially Ni and Cr was conducted using MaTrace model. The aim of the study was to evaluate the dissipation of Ni and Cr in Japan and the potential to reduce dissipation of Ni and Cr. We determined that 45.7% of Ni, and 81.0% of Cr is dissipated into physical losses and that 14.3% of Ni and 9% of Cr is lost as quality loss over 100 years The main causes of the dissipation are the low recovery rate of scrap from end of life products for Ni, the low yield of refining processes for Cr and the low horizontal recycling rate of special steel excluding Ni-type stainless steel for both elements.