Stocks and Flows Project (STAF)

Modern society is made possible by the use of metals, and metals have historically been supplied from virgin stocks (ore bodies, mineral deposits, and the like). Other reservoirs exist, however, a principal one being materials or products in use, stored, or discarded over the years by corporations and individuals. These reservoirs might become very important in the next few decades of rapid population growth and resource and energy use. There are also concerns about the use of energy in the extraction and processing of metals, and realization that the loss of resources by dissipation or landfilling can sometimes be problematic from an environmental standpoint, and concerns over the short and long-term “criticality” of metals.

In the STAF project, we are evaluating current and historical flows of specific technologically significant materials, determining the stocks available in different types of reservoirs and the flows among the reservoirs, developing scenarios of possible futures of metal use, and assessing metal supply and demand. As of fall 2011, the group has completed work on copper, zinc, chromium, lead, iron, nickel, silver, and stainless steel, comprising complete cycle characterizations for all countries using significant amounts of these materials (more than 50), nine world regions including Europe, North America, and Asia, and the planet as a whole. Targeted studies of a few states and cities have also been accomplished. Specialized studies on tin, cobalt, tungsten, and aluminum have been done as well. These comprehensive cycles, and their interpretation and implications, are published in the scholarly literature as they are completed.
 
Key publications on multi-level metal cycles

 
Copper: “The multilevel cycle of anthropogenic copper”, T.E. Graedel, D. van Beers, M. Bertram, K. Fuse, R.B. Gordon, A. Gritsinin, A. Kapur, R. Klee, R. Lifset, L. Memon, H. Rechberger, S. Spatari, and D. Vexler, Environmental Science & Technology, 38, 1253-1261, 2004.

Zinc: “The multilevel cycle of anthropogenic zinc”, T. E. Graedel, D. van Beers, M. Bertram, K. Fuse, R.B. Gordon, A. Gritsinin, E. M. Harper, A. Kapur, R. J. Klee, R. Lifset, and S. Spatari, Journal of Industrial Ecology, 9 (3), 67-90, 2005.

Yang, Y. M., T. E. Graedel, and B. K. Reck. (2014). The Evolution of Zinc Use in Industrialized Countries.Journal of Industrial Ecology, accepted.

Silver: “Contemporary anthropogenic silver cycle: A multilevel analysis”, J. J. Johnson, J. Jirikowic,  M. Bertram D. van Beers, R. B. Gordon, K. Henderson, R. J. Klee, T. Lanzano, R. Lifset,  L. Oetjen, and T. E. Graedel,, Environmental Science & Technology, 39, 4655-4665, 2005.
 
Chromium: “The contemporary anthropogenic chromium cycle”, J. Johnson, L. Schewel, and T.E. Graedel, Environmental Science & Technology, 40, 7060-7069, 2006.

Iron: “Forging the anthropogenic iron cycle”, T. Wang, D. B. Müller and T. E. Graedel, Environmental Science & Technology, 41, 5120-5129, 2007.

Nickel: “Anthropogenic nickel cycle: Insights into use, trade, and recycling”, B. K. Reck, D. B. Müller, K. Rostkowski, and T.E. Graedel, Environmental Science & Technology, 42, 3394-3400, 2008.

Eckelman, M. J., B. K. Reck, and T. E. Graedel. 2012. Exploring the global journey of nickel with Markov models. Journal of Industrial Ecology 16(3): 334-342.
 
Lead: “The multilevel cycle of anthropogenic lead”, J.S. Mao, J. Dong, and T.E. Graedel, Resources, Conservation, and Recycling, 52, 1050-1057, 2008.

Stainless steel: “Global stainless steel cycle exemplifies China’s rise to metal dominance”, B. K. Reck, M. Chambon, S. Hashimoto, and T.E. Graedel, Environmental Science & Technology, 44, 3940-3946, 2010.

Platinum: Nassar, N. T. 2013. Anthropospheric losses of platinum group elements. In Element recovery and sustainability, edited by A. J. Hunt: The Royal Society of Chemistry.

Tellurium: Kavlak, G. and T. E. Graedel. 2013b. Global anthropogenic tellurium cycles for 1940-2010. Resources Conservation and Recycling 76: 21-26.

Selenium: Kavlak, G. and T. E. Graedel. 2013a. Global anthropogenic selenium cycles for 1940-2010. Resources Conservation and Recycling 73: 17-22.

Cobalt: Harper, E. M., G. Kavlak, and T. E. Graedel. 2012. Tracking the Metal of the Goblins: Cobalt's Cycle of Use. Environmental Science & Technology 46(2): 1079-1086.

Special Topics Explored by the STAF Project (selection)

Chen, W. Q.; Graedel, T. E., Anthropogenic Cycles of the Elements: A Critical Review. Environ. Sci. Technol., 46, (16), 8574-8586, 2012.

Ciacci, L., W. Q. Chen, F. Passarini, M. Eckelman, I. Vassura, and L. Morselli. 2013. Historical evolution of anthropogenic aluminum stocks and flows in Italy. Resources Conservation and Recycling 72: 1-8.

Reck, B. K. and V. S. Rotter. 2012. Comparing growth rates of nickel and stainless steel use in the early 2000s. Journal of Industrial Ecology 16(4): 518-528.

Urban mines: “Copper mines above and below the ground”, A. Kapur and T.E. Graedel, Environmental Science and Technology, 40, 3135-3141, 2006.

Graedel, T. E., The prospects for urban mining. The Bridge, pp 43-50, 2011.

Spatial analysis of metal stocks: “Spatial characterization of multi-level in-use copper and zinc stocks in Australia”, D. van Beers and T.E. Graedel, Journal of Cleaner Production, 15, 849-861, 2007.

Rauch, J. N., Global mapping of Al, Cu, Fe, and Zn in-use stocks and in-ground resources. Proc. Natl. Acad. Sci. U. S. A. 2009, 106, (45), 18920-18925.

In-use stocks: “Exploring the engine of anthropogenic iron cycles”, D.B. Müller, T. Wang, B. Duval and T.E. Graedel, Proceedings of the National Academy of Sciences of the US, 103, 16111-16116, 2006.

Chen, W. Q.; Graedel, T. E., Dynamic analysis of aluminum stocks and flows in the United States: 1900-2009. Ecological Economics, 81, 92-102, 2012.

Metal in products: “The ‘Hidden Trade’ of metals in the United States”, J. Johnson and T.E. Graedel, Journal of Industrial Ecology, in press, 2008.

Loss of metal to the environment: “Silver emissions and their environmental impacts: A multilevel assessment, M. J. Eckelman and T.E. Graedel, Environmental Science & Technology, 41, 6283-6289, 2007.

Lifset, R. J.; Eckelman, M. J.; Harper, E. M.; Hausfather, Z.; Urbina, G., Metal lost and found: Dissipative uses and releases of copper in the United States 1975-2000. Sci. Total Environ., 417, 138-147, 2012.

Recycling: Reck, B.K.; Graedel, T.E.' Challenges in metal recycling. Science, 337, 690-695, 2012.

Graedel, T. E.; Allwood, J.; Birat, J.-P.; Buchert, M.; Hagelüken, C.; Reck, B. K.; Sibley, S. F.; Sonnemann, G., What Do We Know About Metal Recycling Rates? Journal of Industrial Ecology, 15, (3), 355-366, 2011.

Eckelman, M. J., L. Ciacci, G. Kavlak, P. Nuss, B. K. Reck, and T. E. Graedel. (2014). Life Cycle Carbon Benefits of Aerospace Alloy Recycling. Journal of Cleaner Production, in review.

Nassar, N. T. 2013. Anthropospheric losses of platinum group elements. In Element recovery and sustainability, edited by A. J. Hunt: The Royal Society of Chemistry.

Nuss, P. and Eckelman M. J. 2014. Life cycle assessment of metals: A scientific synthesis. PLOS one 9(7): 12pp (e101298).