Metal Stocks, Flows, and Sustainability

Transcription

1 Center for Industrial Ecology Yale School of Forestry & Environmental Studies Metal Stocks, Flows, and Sustainability Thomas E. Graedel Yale University Total Material Consumption: Neolithic Human Breath Excreta +0 Solid waste 0.1 Unit: tonnes/cap-yr 1

2 Total Material Consumption: Modern Human Offgas Solid waste 3 Sewage Unit: tonnes/cap-yr US 20 th Century Materials Use 2

3 Big Questions for the Yale Stocks and Flows (STAF) Project How much do we know about the ways in which modern society uses metals? How much metal exists in in-use stock, and where is it located? How much metal is discarded to landfills, or lost by dissipation from in-use stocks? Should we mine tailings, slag, landfills? Are supplies of any metals of long-term concern and, if so, which ones? How Do We Characterize a Metal Cycle? 3

4 IMPORT/EXPORT PROCESS- ING FABRICA- TION USE WASTE DISCARD MGT. ORE ENVIRONMENT STAF Project Yale University 2004 European countries Building Multilevel Materials Cycles Asian countries Planet Earth Other countries Nine regions STAF Project, Yale University 4

5 STAF Project Emphases: International Trade of Metal in Products, Total Flow into Use, Metal Added to In-Use Stock, Discard Management and Recycling Typical data availability (with emphasis on metal content) I/E Import / Export Production P Fabric. & Manuf. F U 4 Use Recycling & Waste W Mgt. Ore STAF Project Yale University 2006 Repositories data available through statistics (USGS, etc) few data available, typically estimated by Yale data known to industry, but usually not available in statistics 5

6 Status of the STAF Project Al Cr Fe Ni Cu Zn Nb Mo Rh Pd Ag Sn W Pt Pb Blue: Multilevel cycle complete Green: Multilevel cycle in preparation Yellow: Under discussion Red: Stock determination performed What is the Structure of the STAF Database? Because of differences in the data structure, four kinds of tables have been developed: Geography (for metadata like population or land area) Flows Stocks References Information in the different tables is linked through the Relational DataBase (RDB) Within a table, each data entry is uniquely identified through a Record ID (i.e., Geography Record ID, Flow Record ID, Stock Record ID, and Reference ID). 6

7 A Sampling of Results from the STAF Chromium Project Japan Waste Management, Chromium WM Ca Import/Export -24 Old Scrap 24 Discards 152 Old Scrap 109 Collection, Separation, and Treatment Landfill, Waste, Dissipated Landfill 67 STAF Project, Yale University Gg Cr/yr 7

8 Japan Chromium Cycle: One Year Stocks and Flows, 2000 Import/Export Ore, Concentrate Production FeCr 441 FeCr 521 Chem 15 Ref Semis 155 Fabrication & Manufacturing Products 36 Products 400 IW 71 HW 5.4 Use 324 Stock Discards 76 Old Scrap 24 Waste Management & Recycling FeCr Slag 16 Prompt 73 Downgraded Scrap 106 Old Scrap 109 Landfill, Waste, Dissipated 67 Ore Environment STAF Project, Yale University Gg Cr/yr FeCr = ferrochromium; IW = industrial waste; HW = hazardous waste; Ref = refractories South Africa Chromium Cycle: One Year Stocks and Flows, 2000 Import/Export Ore, Concentrate Ore 2,156 Tailings 263 Production FeCr Slag 268 FeCr 1129 FeCr 210 Chem 20 Ref Metals from Slag 36 Semis 73 F&M Prompt 6.9 Products 4.9 Products 20 Downgraded Scrap 9.6 IW 26 HW 3.2 Use 16 Stock Discards 4.3 Old Scrap 10 Old Scrap 8.5 Waste Management & Recycling Landfill, Waste, Dissipated 15 Ore Environment STAF Project, Yale University Gg Cr/yr FeCr = ferrochromium; IW = industrial waste; HW = hazardous waste; Ref = refractories 8

9 Computing Copper Resource Stock In Use Quantifying stock per capita Step 1: Determine content of major reservoirs Typical auto 21 kg Cu Typical house 200 kg Cu 9

10 Quantifying stock per capita Step 2: Multiply by the number of units in the reservoirs Copper Stock per capita 144 kg Cu 35 kg Cu New Haven Beijing 10

11 Annual Copper Usage: Where Are We Headed? (Tg/year) Year Copper Stock and Copper Need 144 kg Cu 144 kg Cu New Haven Beijing 1.3 Pg Cu Global need in

12 Limits to Materials: Copper Stock and Copper Supply 144 kg Cu 144 kg Cu New Haven Beijing 1.3 Pg Cu 1.6 Pg Cu Global need in 2040 Global resource Is There a Saturation Point for Iron Stock In Use? 12

13 Distribution of iron stocks in the U.S. Yale CIE Beijing s National Stadium: An Iron Repository Floor area: m 2 Steel use: 41.8 Gg 335 kg/m 2 13

14 Transport Technologies and Iron Intensity No iron 10 Mg Fe/bus 170 kg Fe/cap 1 Mg Fe/car 670 kg Fe/cap Multilevel Iron Stocks Shanghai Beijing China, rural China, urban China New Haven Connecticut US (TD) Per Capita Iron Stocks-In-Use (Mg Fe/cap) 14

15 Iron stocks in use Hypothesis: Per capita iron stock in use is an indicator for the degree of industrialization. Implication: Experiences of iron stock saturation levels of industrialized countries can be used for long-term forecasting of iron (and steel) demand in developing countries. Yale CIE Unanticipated Trouble for Metals? 15

16 New Mineralogy Technological products (computers, cars, etc.) are recovered and reprocessed Typically the products contain a suite of co-occurring metals in combinations unfamiliar to nature (and thus to traditional ore processing technology) To make the new mineralogy work, the products must be recovered and then recycled with high efficiency A Mine of the Future 16

17 Summary Increasingly, metal stocks are moving from below ground to above, from ores to cities For some metals, but not all, there are suggestions of in-use stock saturation The sustainability of resource supplies is not assured, and it is imperative that we better understand how we use (and how we lose) the metals given to us by nature Thanks to our Sponsors! IAI U.S. National Science Foundation 17