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Environmentally Conscious Design & Manufacturing. Class 2: Industrial Ecology & Manufacturing. Prof. S. M. Pandit. Industrial Ecology and Manufacturing Case Study: The Automobile - A Discrete Manufactured Product. Agenda Environmental Impact “The Master Equation”
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Environmentally Conscious Design & Manufacturing Class2: Industrial Ecology & Manufacturing Prof. S. M. Pandit
Industrial Ecology and Manufacturing Case Study: The Automobile - A Discrete Manufactured Product Agenda • Environmental Impact “The Master Equation” • Automobile sub-systems & Environmental Impact • Environmental interactions during manufacturing • Energy consumption & Motive energy options • Infrastructure: Embedded energy in roads • Environmental interactions during product use References: Graedel & Allenby “Industrial Ecology and the automobile” EPA Web
The Master Equation Quantitative estimates of the environmental impact in a particular locality (or eco - system) Gross Domestic Product Population Env. impact per unit of GDP
The Master Equation E = [P] [ip P = P0 exp {Rt} E = Environmental Impact P = Population (temporal) ip= Gross Domestic Product(GDP) / person = Environmental Impact / GDP Po =Initial population t = Time R = Net rate of growth = (Rb - Rd) + (Ri - Re)
The Master Equation E Pip Time
The Master Equation As we move towards sustainable manufacturing, The environmental impact surface should become flatter. d/dt [Pollutant generation] < d/dt [Pollutant processing] Short / Long term implications
Automobile Sub-systems & Environmental Impact Societal & Cultural Factors Constituents Environmental impact Design Questions Addressed Sub-systems ? Impact of design and materials - Technology focus
Automobile Sub-systems & Environmental Impact Chassis Frame Engine Brakes Cooling systems Lubrication Tires Fuel Paint Emission Control Electrical power Electronics Mechanics, Thermofluids Overview of Sub-Systems Tribology Chemical processing, Thermofluids Machines, Signal processing
Automobile Sub-systems & Environmental Impact Time - Temperature dependent diffusion of C in Fe Materials selected (how do we look at properties?) : Ferrous Cast Irons Steel Alloy steels Aluminum alloys Ceramics Composites Polymers Fluids Engine / Transmission / Brake / Battery Ref: http://ate.cc.vt.edu/eng/materials/classes
Automobile Sub-systems & Environmental Impact • Environmental • Impact • Raw Material depletion • Combustion by-products • Manufacturing Process Waste Streams
Automobile Sub-systems & Environmental Impact • Design factors and Environmental Impact • Combustion Efficiency • Weight • Corrosion resistance • Ease of Manufacturing • Functionality • Cost • Recyclability
Environmental Interactions during Manufacturing Upstream Input(s) Raw Materials & Energy Manufacturing process Waste Streams Downstream Output(s)
Environmental Interactions during Manufacturing • Typical Manufacturing Processes, inputs and outputs • What can we do with these? • Develop analytical I/O models • - Based on experimental data (Regression,DDS) • - Based on a physical understanding of the process • (still using models developed to describe basic • interactions; e.g. rate phenomenon in chemical • metallurgy to describe chemistry change and • effluents in welding processes)
Environmental Interactions during Manufacturing Aromatic hydrocarbons released from binder. & Heat released - Sand discarded after use Casting & Forming: Other Processes: Die Casting, Injection molding, Welding and Brazing, Metal Plating, Painting
Environmental interactions during manufacturing “Greening” the manufacturing processes (How) - Energy management - Better mold utilization - Reuse of contaminated water - Waste water treatment options - TRANSITION TO NEW PROCESSES?
Energy Consumption (urban use) Other losses Aero: 10.9% Rolling: 7.1% Braking: 2.2% Standby (3.6%) Accessories (1.5%) Engine Engine Losses (69.2%) Driveline losses (5.4%)
Energy Consumption (options) C - Based Fuels CH3OH High Cost, Smog, Global Warm Nat. Gas High Cost, Smog, Global Warm C2H5OH High Cost, Smog, Bio. Corn-based: 5% of needs
Energy Consumption (options) Electric Vehicles: - Electro-Chemical Batteries - Electromechanical Batteries Hybrid power Fuel Cells
Energy Consumption (options) Hybrid: Fuel economy of 66 mpg and emission reductions of 50% for carbon dioxide and 90% for carbon monoxide, hydrocarbons and nitrogen oxide
Energy Consumption (options) About Fuel Cells Ref: http://www.benwiens.com/energy1.html
Infrastructure: Embedded Energy in Roads Material Embedded Energy(J/kg) Bitumen 0.63 Cement 6.70 Aggregate 0.07 Reinforcing steel 23 Steel Beams 18
Infrastructure: Embedded Energy in Roads Energy / km of urban roads 8.4 x 1012J Total Embedded Energy: (x1018J) Roads: 190 Bridges: 1.5 Estimated worldwide “embedded energy” in roads
Environmental Interactions during Product Use • Auto use residues or potential waste streams • {Principal Environmental Impact occurs during use, and • this is therefore the most “significant” life cycle stage} • Solids • Liquids • Gaseous
Environmental Interactions during Product Use Liquids: Oil Antifreeze Battery Acids Solids: Batteries (10% lead loss) Tires (freeze and grind?) Scrap - How do you quantify?
Environmental Interactions during Product Use Gaseous Emissions: In many urban areas, motor vehicles are the single largest contributor to ground-level ozone, a major component of smog. Ground-level ozone is the most serious air pollution problem in the northeast and mid-Atlantic states. - EPA http://www.dieselnet.com/standards/cycles
Environmental Interactions during Product Use Cars also emit several pollutants classified as toxics, which cause as many as 1,500 cases of cancer in the country each year. Auto emissions also contribute to the environmental problems of acid rain and global warning. - EPA Ref: http://www.nsc.org/ehc/mobile/mse_fs.htm
Environmental Interactions during Product Use CxHy: Hydrocarbons react with nitrogen oxides in the presence of sunlight and elevated temperatures to form ground-level ozone. It can cause eye irritation, coughing, wheezing, and shortness of breath and can lead to permanent lung damage.
Environmental Interactions during Product Use NOx Nitrogen oxides also contribute to the formation of ozone and contribute to the formation of acid rain and to waterquality problems. CO Carbon monoxide is a colorless, odorless, deadly gas. It reduces the flow of oxygen in the bloodstream and can impair mental functions and visual perception. In urban areas, motor vehicles are responsible for as much as 90 percent of carbon monoxide in the air.
Environmental Interactions during Product Use • Clean - up • the toxins (How?) • Chemical Catalysis • Absorption • Adsorption • How about bio-degradation? http://news.pollutiononline.com/common
Environmental Interactions during Product Use • Where From? • When outside temperatures on hot, sunny days cause a car's fuel to evaporate • Hot engine and exhaust system of a running car cause the fuel to become heated • When the car is shut off and remains hot enough to cause fuel to evaporate • During refueling, when gasoline vapors escape into the air from the gas tank and the nozzle