Mapping the Global Anthropogenic Chromium Cycle: Implications for Resource Efficiency and Potential Supply Risk

Chromium (Cr) is a critical metal due to its non-substitutable
application in the metallurgy industry and highly uneven distribution
of global reserve. However, there is a lack of in-depth analysis of
global Cr flow patterns and its trade networks among individual cycles,
which leaves the potential barriers and opportunities unexplored for
improving chromium resource efficiency. Here, we employ a trade-linked
multilevel material flow analysis (MFA) to map the global anthropogenic
Cr cycle for year 2019. Social network analysis is also used to identify
the key countries involved in the global Cr trade network. The results
highlight that the global Cr cycle depends substantially on international
trade in different forms, of which stainless steel is the leading
application. Although South Africa, Kazakhstan, and Turkey are the
major Cr primary resource suppliers, China and India play substantial
roles in manufacturing Cr-containing products. Regional disparities
exist in the scrap contents of individual country cycles, varying
from 7% (uncertainty ranges from 4 to 11%) in China to 88% (uncertainty
ranges from 87 to 89%) in India. Additionally, several countries are
essential in the global Cr redistribution and in the connectivity
of the Cr trade network, which may lead to their strong import dependence
and even supply disruption.