Green Engineering

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Green Engineering

• Jess Everett
• A number of the slides were adopted
• from a presentation by Dr. Robert Hesketh

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Green Engineering

• Design, commercialization and use of processes
  and products that are feasible and economic while
  minimizing
• Generation of pollution at the source
• Risk to human health and the environment
• US EPA

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Sustainable Development

• Sustainable development meets needs of present
  without compromising ability of future
  generations to meet needs
• World Energy Council

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Industrial Ecology

• Systematic examination of
• local/regional/global
• uses/flows of
• materials/energy in
• products/processes/industrial sectors/economies
• Focuses on potential role of industry in reducing
  environmental burdens throughout product life
  cycle

Journal of Industrial Ecology
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Life Cycle Assessment
Materials
Materials
Materials
Materials
Life- Cycle Stages
Energy
Energy
Energy
Energy
Raw Materials Extraction
Material Processing
Product Manufacturing
Use, Reuse, Disposal
Wastes
Wastes
Wastes
Wastes
Life- Cycle Impacts
Human health and ecosystem damage
global warming
ozone depletion
smog formation
acidifi- cation
other toxic releases
-Robert Hesketh
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20W compact fluorescent lamp compared to 75W
incandescent lamp
-Robert Hesketh
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Green Design Initiative

• Reduce environmental damage by
• Minimizing use of non-renewable resources
• Reducing use of renewable resources to
  sustainable levels
• Lowering environmental discharges

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Engineers and Environmental Regulations
Major Laws/Amendments
Environmental Regulations
Bishop, Pollution Prevention Fundamentals and
Practice, McGraw-Hill, 2000
-Robert Hesketh
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U.S. Energy Flows, 1997
Annual Energy Review 1997, U.S. DOE, Energy
Information Administration, Washington, DC,
DOE/EIA-0384(97)
-Robert Hesketh
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Global Warming and Related Impacts
Energy
Materials
Cause and Effect Chain
Products
Process of Concern
greenhouse gas emissions CO2, CH4, N2O
climate change sea level change
human mortality or life adjustments
Contribution to global Warming Phipps, NPPC,
http//www.snre.umich.edu/nppc/
Climate Change 1995, Intergovernmental Panel on
Climate Change, WMO and UNEP, Cambridge
University Press, 1996.
-Robert Hesketh
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Stratospheric Ozone and Related Impacts
Cause and Effect Chain
Energy
Materials
Products
Process of Concern
ozone depleting substances CFCs, HCFCs
human mortality or life adjustments ecosystem
damage
ozone layer loss increase in uv
Toxics Release Inventory Data
Climate Change 1995, Intergovernmental Panel on
Climate Change, WMO and UNEP, Cambridge
University Press, 1996.
-Robert Hesketh
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Smog formation and related impacts
Cause and Effect Chain
Energy
Materials
Products
Process of Concern
human/ecological damage from O3 and other oxidants
NOx and volatile organic substances
photochemical oxidation reactions
1 - Chemical Allied Processing 2 - Petroleum
Related Industries
NOx
VOCs
NOx
1997
Miscellaneous
3 - Metals Processing, 4 - Other Industrial
Processes 5 - Solvent Utilization, 6 - Storage
Transportation 7 - Waste Disposal Recycling
Transportation
Industrial Processes
VOCs
1997
Fuel Combustion
National Air Quality and Emissions Trends Report,
1997, U.S. EPA Office of Air Quality Planning and
Standards, http//www.epa.gov/oar/aqtrnd97/chapter
2.pdf
-Robert Hesketh
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Acid rain / Acid deposition
Cause and Effect Chain
Energy
Materials
Products
Process of Concern
human/ecological damage from H and heavy metals
SO2 and NOx emission to air
Acidification rxns. acid deposition
SO2
1997
Miscellaneous
1 - Chemical Allied Processing 2 - Petroleum
Related Industries 3 - Metals Processing 4 -
Other Industrial Processes 5 - Solvent
Utilization 6 - Storage Transportation 7 -
Waste Disposal Recycling
Transportation
Industrial Processes
Fuel Combustion
National Air Quality and Emissions Trends Report,
1997, U.S. EPA Office of Air Quality Planning and
Standards, http//www.epa.gov/oar/aqtrnd97/chapter
2.pdf
-Robert Hesketh
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Human Health Toxicity
Energy
Materials
Products
Process of Concern
Transport, fate, exposure pathways routes
Human health damage carcino- genic non...
Toxic releases to air, water, and soil
EPCRA Toxic Waste
RCRA Hazardous Waste
Allen and Rosselot, 1997
-Robert Hesketh
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Green Design Tools

• Mass balance analysis
• Green indices
• Design for disassembly and recycling aids
• Risk analysis
• Material selection and label advisors
• Full cost accounting methodologies

Introduction to Green Design, By Chris
Hendrickson, Noellette Conway-Schempf, Lester
Lave and Francis McMichael, Green Design
Initiative, Carnegie Mellon University,
Pittsburgh, PA
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Mass balance analysis

• Trace materials or energy in and out of an
  analysis area
• manufacturing process or plant, watershed
• Ideally based on measured inflows, inventories,
  and outflows
• problems with data availability and consistency

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Green Indices

• Summarize various environmental impacts into
  simple scale
• E.g., compare pound mercury dumped into the
  environment with pound dioxin?
• Designer compares green score of alternatives and
  choose one with minimal environmental impact
• Provide at least rudimentary guidance in choosing
  materials, components, or processes

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Design for disassembly and recycling aids

• Making products that can be taken apart easily
  for subsequent recycling and parts reuse
• Kodaks disposal cameras snap apart, allowing
  87 of the parts (weight) to be reused or
  recycled
• DFD/R acts as a driver for recycling and reuse
• Disassembly may exceed value of materials
• DFD/R software generally calculate potential
  disassembly pathways, point out fastest pathway,
  and reveal obstacles to disassembly that can be
  "designed out"

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Risk analysis

• Tracing through chances of different effects
  occurring
• E.g., risk of toxic emissions estimated by
• estimating amount and type of emissions
• transport in the environment
• ecological and human exposure
• likely damage (such as cancer) as a percent
• All steps have uncertainty
• Integrate effects over several media
• air, water and land

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Basic Concepts Risk Assessment
Exposure
Hazard
Risk

-Robert Hesketh
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Basic Concepts Risk Assessment
Exposure
Hazard
Risk

Concentration in Air, Water Soil (g/m3)
Transmission Rate(m3/s)
Duration (s)
-Robert Hesketh
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Basic Concepts Risk Assessment
Exposure
Hazard
Risk

Permissible Exposure Limit (PEL) Threshold Limit
Value (TLV) No Observable Adverse Effects Level
(NOAEL) Reference Dose (RfD) Reference
Concentration (RfC) Cancer Slope Factors
Human Health Ecosystem EffectsCarcinogenicTox
icity
-Robert Hesketh
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Material selection

• Different materials can produce a particular
  quality component or product, but with different
  environmental implications
• Material selection guidelines attempt to guide
  designers towards the environmentally preferred
  material

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Material Selection Principles

• Graedel and Allenby 1995
• Use abundant, non-toxic materials where possible
• Use materials familiar to nature (e.g.
  cellulose), rather than man-made (e.g.
  chlorinated aromatics)
• Minimize number of materials used in product or
  process
• Try to use materials that have an existing
  recycling infrastructure
• Use recycled materials where possible

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Label advisors

• Marks on materials or products that reveal
  information about material content relevant to
  environment or conservation
• Plastic identification symbol that can be used in
  plastics resorting and recycling efforts
• Eco-labels provide unbiased appraisal of
  environmental benefits of products
• Recycled Content, Energy Saving, Organic, Pest
  Management, Social Responsibility, Sustainable
  Agriculture, Sustainable Fishing, Animal Welfare,
  Sustainable Wood

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Full cost accounting methodologies

• Provide methods to account for ALL costs
  associated with a product, process, activity
• Companies may incur high costs from using a
  material or process that creates environmental
  problems when an environmentally benign material
  or process exists
• Consumers purchase products that create
  environmental problems because they do not know
  about green alternatives
• Example protect bolt from corrosion
• plate with cadmium or use stainless steel bolt
• purchase price of the two bolts
• additional costs to the company of using a toxic
  material

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Green Engineering WEBSITE
http//epa.gov/oppt/greenengineering/