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Green Engineering Profit = Ø. ?. It depends!!!!. The 3M Experience. 130 Manufacturing sites in the US Operations in more than 40 countries One of the largest producers of consumer products It was one of the largest producers of waste, both toxic and nontoxic
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The 3M Experience • 130 Manufacturing sites in the US • Operations in more than 40 countries • One of the largest producers of consumer products • It was one of the largest producers of waste, both toxic and nontoxic • Waste was produced during manufacturing of its products and its raw materials.
The 3M Experience • Late 1960s and early 1970s • Clean Air Act Amendments (CAAA) in 1967 • National Environmental Policy Act (NEPA) in 1969 • Federal Water Pollution Control Act (FWPCA) in 1972 • Clean Water Act (CWA) in 1972 • Safe Drinking Water Act (SDWA) in 1974 • Toxic Substance Control Act (TSCA) in 1976
The 3M Experience • 1975. 3M initiates a Pollution Prevention Program. • Solve its own environmental pollution and conservation problems • Prevent pollution at the source wherever and whenever possible • Develop products with minimum effect on the environment • Assure that its facilities and products meet and sustain all regulations
The 3M Experience RESULTS $ 150 million in lower costs for energy, process chemical, and waste treatment
Pollution Prevention Definition The EPA defines pollution prevention as: the use of material, processes, or practices that reduce the creation of pollutants at the source. It includes practices that reduce the use of hazardous materials, energy or other resources and practices that protect natural resources through conservation or more efficient use.
Pollution Control vs. Pollution Prevention • In the 1970’s, end-of-pipe treatment: • reduce the load or toxicity to acceptable levels. • Conversion techniques such as incineration or biotreatment. • Transform the contaminants into more benign species.
Pollution Control vs. Pollution Prevention • In the 1980’s, strong interest in recycle/reuse of chemicals: • Pollutants are recovered from terminal streams. • Separation processes: chemicals are reused or sold. • Realization that waste streams can be valuable process resources.
Pollution Control vs. Pollution Prevention • At present, there is more substantial industrial interest in the more comprehensive concept of pollution prevention.
What is Pollution Prevention? • Any activity aimed at reducing the release of undesirable chemicals to the environment. • Other terms used: • Waste Management • Waste Minimization • Green Engineering
Why going green? • Compliance • Tougher regulations forecast • Product banned • Company image in community • others
How do we go green? • Alternative Chemical Reaction Paths. • Solvent Modeling. • Green Engineering through Process Integration.
Why is Green Engineering so challenging? Because engineers must select the type of pollution prevention technology, system components, interconnection of units, and operating conditions.
Why is Green Engineering so challenging? • The environmental problem integrates: • All process objectives including: • cost effectiveness • yield enhancement • energy conservation • environmental acceptability • The waste receiving media namely air, water and land.
Contaminant Transport and Transformation in the Environment • Concentration: ppm, ppb, mg/l, mg/l • Loading processes: mechanisms by which pollutants are introduced in the environment. • Advective Process: movement of pollutant away from the source due to physical movement of the medium in which is contained.
Contaminant Transport and Transformation in the Environment • Dispersive Processes: the pollutant mixed with the uncontaminated surroundings due to turbulence or temp. gradients. • Diffusional Processes: individual molecules or ions move due to conc. gradients. • Partitioning Processes: division between two phases.
Contaminant Transport and Transformation in the Environment • Acid-Base Ionization • Solubility • Nonaqueous Phase Liquids: LNAPLs DNAPLs. • Very difficult to remove • The LNAPLs can volatilize or sorb into solids. • Adsorptive Effects: Sorptive properties: absorption and adsorption.
Contaminant Transport and Transformation in the Environment • Volatilization • Transformations: • Hydrolysis • Oxidation-Reduction Reactions • Photochemical Reactions • Biological Transformations
Green Engineering • Process Integration: • Three key components: • - Synthesis • - Analysis • - Optimization