Lecture 2. Ulrike G.K. Wegst Thayer School of Engineering Dartmouth College, Hanover, NH Cummings 106

Transcription

1 Lecture 2 Ulrike G.K. Wegst Thayer School of Engineering Dartmouth College, Hanover, NH ulrike.wegst@dartmouth.edu Cummings 16 MFA 211 UGKW 212

2 Getting Started Guide in CES Help

3 Browse, Search, and Select: Materials

4 Getting Started Guide Slides

5 Browse, Search, and Select: Processes Processing Options for this Material

6 Processes for Age Hardening Wrought Al-alloys

7 Example: Sheet stamping, drawing and blanking

8 Note: Detailed Eco Material Processing Info in Materials Universe

9 Project/Case Study Step 1: Disassembly

10 Disassembly When disassembling your artifact, carefully measure and document (notes, sketches, images): Amount of time required for disassembly does it tell you something about your own skill or successful Design for Disassembly?) Ease of disassembly is it destructive or reversible? Tools required standard or specialist, how many different ones, etc? Number of different materials and amounts each materials used? Consumables required for artifact s function (e.g. energy, water, paper, etc.)? Scope for product take back (technical, economic, legal?)

11 Exploded Diagram of Artifact and Components A clear and well labeled diagram that includes dimensions and/or scale bars. Where do the components fit in relation to each other and the entire artifact? (Document everything very carefully: once the article has been dismantled it may not be possible to reassemble it.) What is the position of each component in the artifact, also relative to others? This is vital to understanding the component s function. What is the function and what are the design requirements for each component?

12 Function and Design Requirements Function and properties to consider for each component: Density of component: it may be important that the artifact is lightweight Mechanical properties: such as stiffness, strength and/or toughness Electrical properties: conducting or insulating Specific functions: some materials might be chosen because they fulfil a specific function within the article (e.g. piezoelectric or ferromagnetic materials) Corrosion resistance: appropriate for lifetime of component and artifact? Aesthetics: is the appearance important? Economics: costs of the raw materials and processing can influence the materials choice as much as its physical properties; for example diamond is an extremely hard material, but it is not widely used due to cost.

13 Materials Each component will probably be reasonably easily identifiable as belonging to one of four classes of materials: Metals Polymers Ceramics Hybrids/Composites

14 Project/Case Study Step 2.1: Analysis of Materials

15 Materials Identification

16 Example: Polymer Identification

17 Project/Case Study Step 2.1: Resources and World Production

18 Annual World Production and Reserves

19 Material Production Concern 1: Resource consumption, dependence 96% of all material Usage 2% of Global energy

20 Carbon to Atmosphere Concern 2: Energy consumption, CO 2 emission 2% of all carbon to atmosphere

21 Project/Case Study Step 2.2: Eco Audit

22 Eco-audit for Design Need: Fast Eco-audit with sufficient precision to guide decision-making 1 resource energy (oil equivalent) 1 emission CO 2 equivalent Distinguish life-phases Energy (MJ) C 2 equiv (kg) This is the life-energy and life-co 2 (as prescribed in ISO 144 and PAS 25) These are potential benefits (could be recovered at end of life)

23 Eco-aware Design: The Strategy (1) The steps Fast eco-audit Analyse results, identify priorities Explore options with What if.. s 6 4 Initial design 6 4 What if.. Different material? Energy (MJ) Energy (MJ)

24 Eco-aware Design: The Strategy (2) The steps Fast eco-audit Analyse results, identify priorities Explore options with What if.. s Look at the first three steps Use CES to select new Materials and/or Processes Recommend actions & assess potential savings 6 Use eco-audit to indentify design objective Energy (MJ) Material Minimize: material in part embodied energy CO 2 / kg Manufacture Minimize: process energy CO 2 /kg Transport Minimize: mass distance transport type Use Minimize: mass thermal loss electrical loss End of life Select: non-toxic materials recyclable materials

25 The CES Eco-audit Tool User inputs User interface Bill of materials Manufacturing process Transport needs Duty cycle End of life choice Data from CES Eco database Embodied energies Process energies CO 2 footprints Unit transport energies Recycling / combustion Eco audit model Outputs (including tabular data)

26 Typical Record Showing Eco-properties

27 The Simple Audit Tool: Levels 1, 2 and 3 Add record Eco Audit Synthesizer Options. ^ 1. Material, manufacture and end of life? 1 Component 1 Cast iron 3% 2.4 Casting Recycle 1 Component 2 Polypropylene %.35 Molding Landfill How many? Name v 2. Transport? Choose material from CES DB tree Set recycle content 1% Enter mass Choose process Choose end-oflife path v 3. Use? HELP at each step v 4. Report?

28 Material and Process Energy / CO 2 Component name Material Process Mass (kg) End of life Component 1 Aluminum alloys Casting 2.3 Recycle Component 2 Polypropylene Polymer Casting molding 1.85 Landfill Reuse Forging / rolling Refurbish Extrusion Component 3 Glass Glass molding 3.7 Reuse Recycle Wire drawing Powder forming Combust Vapor methods Landfill Total embodied energy Total process energy Total mass Total end of life energy Available processes CES EduPack materials tree End of life options

29 Transport Transport stage Transport type Distance (km) Stage 1 32 tonne truck 35 Stage 2 Sea freight 12 Transport energy Transport CO 2 Table of transport types: MJ / tonne.km CO 2 / tonne.km

30 Use Phase Static Mode Energy input and output Power rating Usage Usage Fossil fuel to electric 1.2 kw W days per year kw MW hours hp per day ft.lb/sec kcal/yr BTU/yr Total energy and CO 2 for use Energy conversion path Fossil fuel to heat, enclosed system Fossil fuel to heat, vented system Fossil fuel to electric Fossil fuel to mechanical Electric to heat Electric to mechanical (electric motor) Electric to chemical (lead-acid battery) Electric to chemical (Lithium-ion battery) Electric to light (incandescent lamp Electric to light (LED)

31 Example: Bottled Water (1 units) 1 litre PET bottle with PP cap Blow molded Filled in France, transported 55 km to UK Refrigerated for 2 days, then drunk Number Name Material Process Mass (kg) End of life 1 Bottles PET Molding.4 Recycle 1 Caps Polyprop Molding.1 Recycle 1 Water 1. Transport Stage 1 Use - refrigeration 14 tonne truck 55 km Fossil to electric.12 kw 2 days 24 hrs/day

32 How it looks in CES EduPack 212

33 The Output: Drink Container Energy (MJ) Material Manufacture Transport Use End of life The audit reveals the most energy and carbon intensive steps and allows rapid What if % virgin PET with recycling Carbon (kg) Material Manufacture Transport 1% virgin PET with recycling Use End of life PET Glass?

34 How it looks in CES EduPack 212

35 Change the Materials 1 litre glass bottle with aluminum cap Glass molded Filled in France, transported 55 km to UK Refrigerated for 2 days, then drunk Number Name Material Process Mass (kg) End of life 1 Bottles Soda PET glass Glass Molding mold.4.45 Recycle 1 Caps Aluminum Polyprop Rolling Molding.1.2 Recycle 1 Water 1. Transport Stage 1 Use - refrigeration 14 tonne truck 55 km Fossil to electric.12 kw 2 days 24 hrs/day

36 Glass Bottle Replacing PET 4 Change of scale Energy (MJ) 2 1 Material Manufacture Transport Use End of life Energy (MJ) 4 2 Material Manufacture Transport Use End of life % virgin PET with recycling % virgin glass with recycling Change of scale Carbon (kg) Material Manufacture Transport Use End of life Carbon (kg) Material Manufacture Transport Use End of life % virgin PET with recycling % virgin glass with recycling

37 Use Recycled PET instead of Virgin? Energy (MJ) 2 1 Material Manufacture Transport Use End of life Energy (MJ) 2 1 Material Manufacture Transport Use End of life % virgin PET with recycling % recycled PET with recycling Carbon (kg) Material Manufacture Transport 1% virgin PET with recycling Use End of life Carbon (kg) Material Manufacture Transport Use End of life 1% recycled PET with recycling

38 Is it practical to use recycled PET?

39 Combust instead of Recycle Energy (MJ) 2 1 Material Manufacture Transport Use End of life Energy (MJ) 2 1 Material Manufacture Transport Use End of life % virgin PET with recycling % virgin PET with combustion Carbon (kg) Material Manufacture Transport Use End of life Carbon (kg) Material Manufacture Transport Use End of life % virgin PET with recycling % virgin PET with combustion

40 Ship by air freight, refrigerate 1 days 4 1 Energy (MJ) Material Manufacture Transport Use Disposal Change of scale Energy (MJ) Material Manufacture Transpt Use Disposal % virgin PET with truck transport % virgin PET with air freight Change of scale 5 4 Carbon (kg) Material Manufacture Transport 1% virgin PET with truck transport Use Disposal Carbon (kg) Material Manufacture Transpt 1% virgin PET with air freight Use Disposal

41 So what? CES has two tools-sets to help explore the materials dimension of environmental design Tool 1. Eco-audits allows to implement quick, approximate portraits of energy / CO 2 character of products. Tool 2. Selection strategies (to be introduced in Week 4) allows selection to re-design products to meet eco-criteria, using systematic methods They allow fast audits and systematic materials selection for redesign

42 Recommended Background Reading

43 Preparation for Next Class with Prof. Wegst Textbook and CES Software Read Chapters 3 & 4 in Ashby Textbook (posted on Blackboard) Additional helpful Background Reading: White Papers on Eco Audit and Eco Design (in Help section) Project/Case Study Start disassembly of artifact. An excellent Introduction to the Deconstruction and Investigation of the Materials and Processes Used in your Everyday Item or Article is provided at (Dissemination of IT for the Promotion of Materials Science (DoITPoMS) at University of Cambridge, UK)