Industrial Ecology

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MFA Methodology All Materials
Domestic Environment
Foreign Hidden Flows
Air and Water
Water Vapor
Imports
Exports
Economic Processing
Domestic Extraction
Domestic Processed Output (DPO) (to Air, Land and
Water)
TDO
DMI
TMR
TMI
Stocks
TMO
Domestic Hidden Flows
Domestic Hidden Flows
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MFA Methodology All Materials
Input flows
DMI
Foreign Hidden Flows
Direct Material Input Domestic Extraction
Imports
Imports
Domestic Extraction
TMI
DMI
Total Material Input Direct Material Input
Domestic Hidden Flows
TMR
TMI
TMR
Total Material Requirement Total Material
Input Foreign Hidden Flows
Domestic Hidden Flows
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MFA Methodology All Materials
Output flows
Domestic Environment
DPO
Domestic Processed Output (DPO) Direct
Material Input Net Additions to Stock Exports
Exports
Domestic Processed Output (DPO) (to Air, Land and
Water)
TDO
TDO
Total Domestic Output (TDO) Domestic Processed
Output Domestic Hidden Flows
TMO
TMO
Total Material Output (TMO) Total Domestic
Output Exports
Domestic Hidden Flows
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MFA Methodology All Materials
Domestic Environment
Foreign Hidden Flows
Air and Water
Water Vapor
Imports
Exports
Economic Processing
Domestic Extraction
Domestic Processed Output (DPO) (to Air, Land and
Water)
TDO
DMI
TMR
TMI
Stocks
TMO
Domestic Hidden Flows
Domestic Hidden Flows
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MFA Methodology All Materials
Input Flows (origin) Domestic extraction Fossil
fuels (coal, oil, etc.) Minerals (ores, gravel,
etc.) Biomass (timber, cereals, etc.)
Imports Fossil fuels, Minerals,
Biomass Semi-finished goods Final Goods Direct
material input (DMI) Unused domestic
extraction from mining/quarrying from biomass
harvest soil excavation Total material input
(TMI) Unused foreign extraction from
mining/quarrying from biomass harvest soil
excavation Total material requirements (TMR)
Output Flows (destination) Emissions and
wastes Emissions to air Waste to
land Emissions to water Dissipative use of
products (Fertilizer, manure, compost, seeds,
paints, pesticides, etc.) Domestic processed
output to nature (DPO) Disposal of unused
domestic extraction from mining quarrying from
biomass harvest soil excavation Total domestic
output to nature (TDO) Exports Fossil fuels,
Minerals, Biomass Semi-finished goods Final
Goods Total material output (TMO)
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MFA Methodology All Materials
Mass balance equation Inflows Outflows Stock
Change
Net Additions to Stock (NAS) Domestic
extraction Imports Direct Processed Output
Exports
Net Additions to Stock (NAS)
Imports
Exports
Domestic Extraction
Domestic Processed Output (DPO) (to Air, Land and
Water)
Stocks
Net Additions to stock (NAS)
Infrastructure and buildings Machinery
durable goods etc.
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Material Flow Perspective of Pollution Prevention

• If pollution is caused by material flows, its
  prevention is also a material issue
• There are essentially three ways to reduce or
  prevent pollution
• Dematerialization (less material to achieve the
  same function)
• Substitution (different substance or material)
• Reuse recycling (use material and value-added
  over and over)

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Dematerialization examples

• Advanced High Strength Steels (AHSS) in
  automotive applications (25 weight reduction)
• Mass reduction of beverage containers
• Continuous casting technology in metals
  production
• Drip lines instead of sprinklers for irrigation
• Carsharing business models
• Spaceframe design concept
• Miniaturization in the electronics industry
  (e.g. precious metal content in consumer
  electronics)

Dematerialization typically has a natural
economic driver and is also often done in
conjunction with material substitution.
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Dematerialization / Resource Productivity
Material flow indicator
Decoupling from economic growth
GDP
Material flow indicator
Decoupling from population growth
Capita
Generic environmental indicator
Environmental Kuznets Curve
GDP per Capita
Hypothesis Dematerialization occurs naturally as
nations get wealthier

• Criticism
• Trans-materialization
• Re-materialization
• Earths carrying capacity is absolute not relative

• 3 main ways for dematerialization
• Increase primary resource productivity
• Decrease material intensity of consumption
• Increase resource productivity through reuse and
  recycling

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Material substitution examples

• Steel versus aluminum versus plastics versus
  composites in automotive
• Steel versus concrete versus timber in
  construction
• Glass versus steel versus aluminum versus PET
  versus laminated cardboard in packaging
• MTBE instead of lead as oxygenate in automotive
  fuels
• Bio-based plastics versus petroleum-based
  plastics (e.g. polylactic acid)
• Lead-based solder versus lead-free solder (e.g.
  tin silver copper antimony alloy,
  
  tin copper selenium alloy, etc.)

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Material substitution Case study 1 Lead-free
solder
Background Electronics industry consumes around
90 Kt pa of lead-based solder
(60Sn-40Pb), 25-50 of which is process waste
(recycling rate ?). Issue Toxicity
of lead (EU ROHS Directive 2002/95/EC bans lead
in EEE) Substitute Lead-free solder (e.g.
the one announced by Sony in 1999
93.4 tin, 2 silver, 4 bismuth, 0.5
copper and 0.1 germanium)
ADP (kg antimony eq.) HTP (kg 1,4-dichlorobenzene eq.) Emission to soil
Lead 0.0135 3281
Tin 0.033 13
Silver 1.845 -
Bismuth 0.0731 -
Copper 0.00194 94
Germanium 0.00000147 -
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Material substitution Case study 1 Lead-free
solder

• Lead-free solder announced by Sony in1999
• 93.4 Sn, 2 Ag, 4 Bi, 0.5 Cu and 0.1 Ge
• New issues
• Production capacity for increased use of
  alloying materials If all solder was based on
  Sonys alloy, world production would increase as
  follows Sn 12, Ag 11, Bi 89, Ge 103
• Bismuth by-product of mining other metal,
  especially lead, copper and tin
• Depletion of some of the alloying metals

Current depletion time Depletion time with 100 Sony solder
Tin 27 20
Silver 16 14
Bismuth 30 16
Copper 35 35
Germanium 35 17
Alternative Electrically conductive adhesives
(polymer binder plus conductive filler)?
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Material substitution Case study 2 Bio-based
plastics
Background Production of plastics worldwide
consumes around 270 MMT pa of fossil
fuel, 120 MMT as feedstock and another
150 MMT as process energy. Issues
Depletion of fossil fuels
Additives (plasticizers, stabilizers, flame
retardants, blowing agents) Lack of
biodegradability (growing and persistent solid
waste stream) Substitute Bio-based
polymers (e.g. PLA or PHA) Examples
NatureWorks (Cargill Dow Polymers, USA)
packaging films, bottles,
textile fibers based on polylactic acid from
maize fermentation
GreenFill (GreenLight Products, UK) loosefill
packaging derived from
wheat starch Mater-Bi
(Novamont, Italy) films, tableware, nappies
based on a copolymer of
maize starch and polycaprolactone
(PotatoPak, UK) supermarket display
trays based on potato starch
(Rodenburg Polymers, NL) packaging
materials from potato starch
NatureFlex (Surface Specialities, UK)
cellulosic packaging films
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Material substitution Case study 2 Bio-based
plastics
American Society for Testing and Materials (ASTM)
definition Biodegradable plastic a degradable
plastic in which the degradation results from
the action of naturally occurring microorganisms
such as bacteria, fungi and algae. The first
compostable logo for cutlery went to Nat-Ur. The
Biodegradable Products Institutes (BPI) symbol
demonstrates that the product meets the ASTM
D6400 Specifications for Compostable Plastics.
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Material substitution Case study 2 Bio-based
plastics

• European Standard for biodegradability is BS EN
  13432 (2000)
• Biodegradation over 90 compared with cellulose
  in 180 days under conditions of
  controlled composting using
  respirometric methods (ISO14855)
• Disintegration over 90 in 30 months (ISO FDIS
  16929)
• Ecotoxicity test results from aquatic and
  terrestrial organisms (Daphnia magna,
  worm test, germination test) as for
  reference compost
• Absence of hazardous chemicals (included in the
  reference list)

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Material substitution Case study 2 Bio-based
plastics

• In an LCA the cradle-to-gate GHG emissions of
  polyhydroxyalkanoate (PHA), a bio-polymer
  extracted from genetically modified corn, were
  compared to those of polyethylene (PE).
• New issues
• The extraction process of PHA from corn stover
  is quite energy intensive.
• If the extraction energy comes from fossil
  fuels, the cradle-to-gate GHG emissions of PHA
  are higher than those of PE.
• Cradle-to-gate GHG emissions of PHA are lower
  than those of PE only if the stover is burned
  for energy generation, i.e. no fossil fuels are
  required for PHA extraction.

Material (fuel) PHA (biomass) PHA (natural gas) PHA (coal) PHA (oil) LDPE HDPE
g CO2 eq / kg of resin -4,000 3,800 5,400 5,000 2,800 2,200
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Reuse and RecyclingFrom Supply Chains to Supply
Loops
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From supply chains to supply loops
Traditional supply chains end with the sale and
delivery of the final product
Raw materials mining
Primary materials production
Component manufacture
Final product assembly
Product sale and delivery
Lee Billington, for example, define a supply
chain as a network of facilities that
procure raw materials, transform them into
intermediary goods and then final products, and
deliver the products to customers through a
distribution system.
Product demand use
End-of-life product disposal
What happens to the product after sale and
deliveryis of no concern for supply chain
managers
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Supply loops divert end-of-life products from
landfill and reprocess these products, their
components or their materials into secondary
resources which replace primary resources in
forward supply chains.
Raw materials mining
Primary materials production
Component manufacture
Final product assembly
Product sale and delivery
Product demand use
Component re- processing
Product re- processing
Materials re- processing
End-of-life product disposal
Eol product collection inspection
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A supply loop is constrained when it is not able,
for technical or economic reasons, to reprocess
all targeted arising end-of-life products into
secondaryoutput that is marketable a above-cost
prices.
Raw materials mining
Primary materials production
Component manufacture
Final product assembly
Product sale and delivery
Product demand use
Component re- processing
Product re- processing
Materials re- processing
End-of-life product disposal
Eol product collection inspection

• The reasons can be
• Limited collection of end-of-life products

• Limited feasibility of reprocessing

• Limited market demand for the reprocessed
  secondary resources

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Supply Loops
Reuse and recycling Environmental benefits
1.
2.
Production
Disposal
Use

1. Diversion of product or process waste from
   landfill or incineration by collecting them for
   economic value recovery via reprocessing.
2. Generation of secondary resources from product
   or process waste and displace primary
   resources, i.e. materials, components and
   products.

The environmental benefits from displacement can
be significantly higher than the benefits from
avoided landfill / incineration.
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Supply Loops - Material Recycling - Definitions
Product manufacturing
Use
Material Production
Disposal
Material reprocessing
eol recycling efficiency rate Eol collection
rate Eol reprocessing yield
recycling input rate recycling efficiency rate
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Supply Loops Materials Recycling Infinite
Cycles
Materialsproduction
End-of-life product disposal
Materials use
is the recycling efficiency rate for each cycle
Question How much recycled material do I get
from m primary material?
Total amount of material (assuming unlimited
recyclability) is Summing this series gives of
which
is secondary (recycled)
material. Overall recycling efficiency rate
Example ? 0.66, m 1kg M 3kg 1kg
primary 2kg secondary
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Supply Loops Basic Environmental Performance
Production Eprod
End-of-life disposal Edisp
Use Euse
Collection Ecoll
Reprocessing Erepro

• Life cycle impact (of a chosen environmental
  impact category)
• Without recycling
• With recycling
• Change in life cycle impact
• Recycling reduces life cycle impact if

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Supply Loops
Basic Environmental Performance Examples
Material Primary Production (cradle-to-gate in MJ/kg) Secondary Production (cradle-to-gate MJ/kg) Savings Factor
Steel 21.7 7.1 3
Aluminum 194.7 10.3 19
Copper 100 20 30 3.3 - 5
Glass 12 7.2 1.7
PET 82.7 ? ?
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Due Date of Assignment 3 Wednesday, 27 February
Reading for Friday, 22 FebruaryGeyer
Jackson (2004) Supply loops and their
constraints The industrial ecology of reuse and
recycling, Cal Man Rev 46(2), 55-73Davis et al.
(2007) Time-dependent MFA of iron and steel in
the UK, Resources, Conservation Recycling
51(2007), 118-140(is posted on course website)