9 IE 7Feb 07 web

Slide1 : Industrial Ecology Pig iron 2.5% Carbon Steel 0.1-2% Carbon Wrought iron <0.1% Carbon Stainless steel <1.2% Carbon, >10.5 % Chromium


Slide2 : Natural Environment Raw Materials Final Products Productive Capital extraction extraction waste production waste recycling material consumption product manufacturing product waste product waste recycling product remanufacturing production waste Industrial ecology: Biogeochemical analogy – R U Ayres


Slide3 : Industrial ecology: Biogeochemical analogy – R U Ayres Inorganic sedimentary rock sulfate phosphate carbonate Nutrients carbon nitrogen phosphorus sulfur Bio-products (non-living) humus detritus Biomass (living) mobilization sequestration regeneration assimilation (photosynthesis) death excretion sequestration mobilization regeneration


Slide4 : Industrial ecology: Food chain analogy – T E Graedel Primary Producer Smelter Primary Consumer Wire producer Secondary Consumer Cable producer Tertiary Consumer Computer manufacturer Solar energy Extractor Miner Secondary producer Recycler Collector Top Consumer Customer Concentrated copper ore Copper ore Production waste Lost material Copper ingots Copper wire Data cable Copper ingots Eol PC PC Recyclables Reusables


Slide5 : Industrial ecology: Food chain analogy – T E Graedel Primary Producer Plankton Primary Consumer Invertebrate Secondary Consumer Small fish Tertiary Consumer Large fish Solar energy Extractor Bacteria Decomposer Bacteria Top Consumer Shark Mineral salts Minerals, other resources Excretions, carcasses Inorganic materials Lost material Carcasses


Slide6 : Transformation process Material inputs Energy inputs Wastes & emissions Useful outputs Thermodynamics and Material Flows in the Economy 1. Law of Thermodynamics: Conservation of energy In non-nuclear processes energy can neither be created nor destroyed. Energy can only be transformed from one form into another. The total amount of energy input to a non-nuclear transformation process is thus equal to the total amount of energy output. Conservation of mass The total mass of material inputs into a (non-nuclear) material transformation process is equal to the total mass of material outputs. Conservation of mass per chemical element The total mass of each chemical element is conserved during every (non-nuclear) material transformation process.


Slide7 : 1. Law of Thermodynamics: Quantity of energy during transformations stays the same. Law of Thermodynamics: Quality of energy decreases during transformations (what matters is exergy not energy). 2. Law of Thermodynamics Short form: In a closed system, entropy (disorder) will increase with time until it reaches its highest possible value. What does this mean for material transformation processes (which are open systems): Every order-increasing material transformation processes requires low-entropy energy inputs. Order-increasing material transformation processes turn low-entropy energy inputs into high-entropy energy outputs. Every production process creates waste and/or emissions. Without low-entropy energy inputs materials tend to dissipate during use and disposal. Thermodynamics and Material Flows in the Economy


Slide8 : Direct materials Ancillary materials Low-entropy energy Economic output Wastes & emissions High-entropy energy Transformation process 1. Law of TD 2. Law of TD The material transformation process


Slide9 : Literature Biogeochemical analogy and industrial ecology: Industrial Ecology, Ayres & Ayres, 1996, Edward Elgar Accounting for Resources 1, Ayres & Ayres, 1998, Edward Elgar Accounting for Resources 2, Ayres & Ayres, 1999, Edward Elgar Food chain analogy and industrial ecology: Industrial Ecology, Graedel & Allenby,1995 & 2002, Prentice Hall Thermodynamics and material flows in the economy: The Entropy Law and the Economic Process, Georgescu-Roegen, 1971, Harvard University Press Evolution, Time, Production and the Environment, Faber & Proops, 1990, Springer Integrating Economics, Ecology and Thermodynamics, Ruth, 1993, Kluwer Eco-Thermodynamics: Economics and the Second Law, 1996, INSEAD working paper


Slide10 : Ecosphere Anthroposphere Materials Sink for: Wastes & Emissions Needs & Wants Solar Radiation (Teff ~ 6000K mainly UV, optical and IR) Earth’s Radiation (Teff ~ 300K mainly IR) Services Products Production All materials that enter the economic system will eventually leave it Large amounts of low-entropy energy are needed to drive the economic system All economic activity is essentially dissipative of both energy and materials Low-entropy Energy Material Flows in the Economy high-entropy Energy


Slide11 : ExxonMobil reports annual profits of $25bn Business: US oil giant reports annual profits that exceed the GDP of Syria. More business news Global warming 'may kill off polar bears in 20 years' Life: Many Arctic animals could be extinct within 20 years because of global warming, conservationists warn. Special report: climate change Monday January 31 2005 Search this site Central paradigm of MFA: Mass Balance IN = OUT


Slide12 : Scientists warn growing acidity of oceans will kill reefs Paul Brown, environment correspondent Friday February 4, 2005 The Guardian (UK newspaper) Scientists have given warning of a newly discovered threat to mankind, which will wipe out coral and many species of fish and other sea life. Extra carbon dioxide in the air, caused by the burning of fossil fuels, is not only spurring climate change, but is making the oceans more acidic – endangering the marine life that helps to remove carbon dioxide from the atmosphere. So alarmed have marine scientists become about this that special briefings have been held for government departments. Carol Turley, head of science at Plymouth Marine Laboratory, warned of a "potentially gigantic" problem for the world. Central paradigm of MFA: Mass Balance IN = OUT


Slide13 : Class exercise: You are mining a copper mine with an ore grade of 0.4%. How much ore do you need to extract 1 ton of copper (assuming 100% extraction efficiency) How much of the ore ends up as mining waste? (this waste is called tailings) Grinding copper ore in BC, Canada Concentration of copper ore by froth flotation


Slide14 : Declining ore grades greatly increase the amount of wastes generated during mining and refining Tons of tailings per ton of metal Ore grade X (%) Ore grade (%) → Tailings (tons / ton) (Does not include for overburden or ancillary materials) Examples:


Slide15 : Motivation for Studying Material Flows in the Economy The extraction of material resources has large environmental impacts. Material transformation processes require large quantities of high-grade energy. Once mobilized, many materials / substances create environmental impact / damage when they are released back into the environment. Substances of economic interest are typically intrinsically linked to many other substances, many of those toxic or otherwise environmentally damaging. All mobilized materials will eventually be released back into the environment. Material transformation processes that are higher up in the supply chain tend to be more energy and waste intensive than downstream processes. This creates large incentives for recycling and reuse. Some uses of certain materials are inherently dissipative.


Slide16 : Definition of Material/Substance Flow Analysis (MFA/SFA) According to Bringezu and Moriguchi (2002), MFA / SFA can be defined as the quantitative accounting of material / substance inputs and outputs of processes in a systems or chain perspective. According to Graedel (2002) MFA / SFA is usually employed to answer one or several of the following questions: How much material enters the economic system? How is the material transformed? How much material is added to the stock in use? How much material is recycled? How much material escapes from the economic system to the environment? How much material ends up in landfill? What trends exist in these stocks and flows? MFA / SFA comprises a variety of flow analysis types: Stocks and flows of individual substances, e.g. chlorine, arsenic, cadmium, lead, etc. Stocks and flows of bulk materials, e.g. paper, plastics, aluminum, steel, copper, etc. Stocks and flows of products and their constituent materials, e.g. diapers, batteries, etc. Total material flows on different levels, e.g. national, sectoral, regional, household, etc.


Slide17 : History of MFA/SFA 1800-1850 Concept of metabolism is introduced to describe the sum of biochemical reactions on the level of cells, organs and organisms 1842 Formulation of the Law of Conservation of Energy 1860s The term metabolism is first applied to human societies by Marx to describe material exchanges between man and nature 1880s Geddes develops first national MFA (80 years ahead of his time and largely ignored) 1905 Mass-Energy-Equivalency is formulated by Einstein in his theory of special relativity 1910s Ostwald and Soddy discuss the importance of availability and conversion of energy to human societies and their development, but this never entered the social sciences mainstream 1930s Notion of the ecosystem is established 1940s The metabolism of ecosystems is first studied 1950-1960 Some discussion of the input aspects of societal metabolism (mainly by geographers and geologists) 1969 First modern MFA of a national economy presented by Ayres & Kneese Apply mass balancing to MFA Environmental pollution and its control is a materials balance problem Reduction of wastes and emission by reduction of inputs


Slide18 : Accounting methodology for material stocks: Producing processes Imports Exports Consuming processes Stocks of upstream materials Stocks of downstream materials Stocks outside of boundaries Stocks outside of boundaries Material stock Transformation processes Transportation processes Methodology – Single material or substance


Slide19 : Material production Potential Waste Component fabrication Product Assembly Product Use Raw Material Material Components Products Imports / Exports Domestic Environment Extraction Release Methodology – Single material or substance


Slide20 : Example: Copper Estimated world production in MMT / y End uses in the USA in 2000: Building & construction 42% Electrical & electronic products 27% Industrial machinery & equipment 10% Transportation equipment 10% Consumer & general products 11% Copper has the highest electric and thermal conductivity after silver Highly corrosion resistant Primary production from ore: 50-100 MJ/kg Cu (cradle-to-gate) Secondary production from scrap: ~ 20 MJ/kg Cu (cradle-to-gate)


Slide21 : Example: Copper Flows in North America in 1994 (in kt / y) Import / Export Environment Lithosphere Production: Mill, Smelter, Refinery Fabrication & Manufacturing Use Waste Management Concentrate, Blister, Cathode 325 Ingots 3 Semis, Finished Products 17 Stock 3 Cathode 3270 Prod. Cu 2640 Prod. Alloy 690 Stock 1920 Discards 1410 Old Scrap 190 New Scrap 730 140 Old Scrap 180 330 Tailings & Slag 365 Ore 3130 Landfilled Waste, Dissipated ??? 2200 Source: CIE, Yale 710 1500


Slide22 : Copper entering use in 1994 (in kt / y) 3300 3000 3900 350 280 180 260 Source: CIE, Yale Global consumption: 11.3 million metric tonnes


Slide23 : Copper entering use in 1994 (in kg / y and capita) 8.2 8.4 1.4 1.0 0.9 6.1 0.4 Source: CIE, Yale


Slide24 : Copper leaving use in 1994 (in kg / y and capita) 3.4 2.2 0.4 0.5 0.7 2.0 0.2 Source: CIE, Yale


Slide25 : Copper recycling rate in 1994 50% 80% 64% 30% 90% 82% 38% Source: CIE, Yale


Slide26 : Reading for Monday, 12 February: Materials, A report of the U.S. Interagency Working Group on Industrial ecology, Material and Energy Flows, 1998, Washington DC (is posted on course website as ‘Reading for Lecture 10’)