1. 1 Environmentally Conscious Process Planning Prepared by Felipe Román

2. 2 Last Week… Today Last lectures –Some ECDM assessment tools… For processes: process mapping I/O assessment For facilities & regions: EnviroFacts & TRI Explorer Today –Begin considering environmental concerns during the product development process… particularly in the process planning stage

3. 3 Learning Objectives 1.Know what is process planning and how it fits in the product development process 2.Understand how to carry out environmentally conscious process planning 3.Learn how to quantitatively assess manufacturing environmental loads

4. 4 Focus: Manufacturing Life Cycle Stage Why manufacturing?...

5. 5 Product Development

6. 6 Environmentally Conscious Manufacturing Strategies Good housekeeping Training and supervision Waste handling Material substitution / elimination / addition In-process recycling Process modification Process Planning Part / product modification Source: http://www.fotosearch.com/ICL154/bim_139/http://www.fotosearch.com/ICL154/bim_139/ Adapted from (Sutherland and Gunter, 2001) and (Skerlos 2005).

7. 7 Process Planning Also known as… –Process engineering –Manufacturing engineering –Process design –Process routing Resources –Machines –Auxiliary equipments –Cutting tools –Cutting fluids Figure from Feng and Song, 2000 Process planning is the set of product development activities that determines how a part will be manufactured given product and production specifications.

8. 8 Manufacturing Processes Metal Casting Bulk Deformation / Forming Sheet Metal Forming Material Removal –Traditional Machining –Precision Machining –Deburring –Advanced Machining Surface Preparation –Cleaning –Hardening –Electro-plating –Painting Joining and Fastening / Assembly Polymer Processing Rapid Prototyping Source: http://divisions.asme.org/med/enewsletter/2003july/meT CreportWeb_files/image002.gif. More information can be found at http://erc.engin.umich.edu/. http://divisions.asme.org/med/enewsletter/2003july/meT CreportWeb_files/image002.gifhttp://erc.engin.umich.edu/

9. 9 Some Auxiliary Equipment (Supporting) Air compressors Coolant systems Water softeners Water Recirculation Material/waste handling Chillers Boilers Piping system

10. 10 Some Auxiliary Equipment (Pollution Control) Oil/dust mist collectors Incinerators / oxidizers Wastewater treatment Gondolas & roll offs Chip centrifuges / Chip wringers Briquetting machines Source: http://www.nationalconveyors.com/metal_chip_onl y/metal_chip_processing/chipwringers6.html http://www.nationalconveyors.com/metal_chip_onl y/metal_chip_processing/chipwringers6.html Source: http://www.ars-inc.com/industrial.htmhttp://www.ars-inc.com/industrial.htm

11. 11 Environmentally Conscious Process Planning For traditional machining (turning)… –Process selection –Resource selection Machine selection Auxiliary equipment selection Cutting fluid selection Cutting tool selection –Process parameter, operational sequence selection

12. 12 Turning Process - Lathe Source: http://www.efunda.com/processes/machining/turn.cfmhttp://www.efunda.com/processes/machining/turn.cfm

13. 13 Turning Categories

14. 14 Mass & Energy Balances * Mass & energy balances are your friend… CV Mass balance equation for an open system: Energy balance equation for an open system:

15. 15 Machine-Level Assessment 1.Identify process- related environmental Inputs/Outputs (I/Os) 2.Quantify I/Os Electricity (kWh) Coolant (gals) Wet chips (lbs) Used coolant (gals) Oil mist (mg/m 3 ) 3.Identify mathematical relationship / function for I/Os Elec. = f (x1,x2,x3) Mist = f (y1,y2,y3,…)

16. 16 Some Machine-Level Models Electricity (kWh/yr) Coolant (gals/yr) Wet chips (lbs/yr) Used coolant (gals/yr) Oil mist (mg/m 3 )

17. 17 Operational-Level Assessment Energy = f (z1,z2,…) Coolant = f (w1,w2,…)

18. 18 Some Operational-Level Models For straight turning operations… Cutting energy (kWh) –Cutting force –Machining time Coolant lost from machined part (gals) –Density of cutting fluid –Surface tension of cutting fluid –Cross-sectional area of workpiece Oil mist generated from straight turning (mg/m 3 )

19. 19 Different Cleaning Processes

20. 20 Aqueous Cleaning Processes Direct consumptionClosed-loop consumption Source: http://www.karcher.ca/CCE/HD%20- %20HDS%20Web%20Pages/Features/Powe rNozzle%20Spray%20Others.jpghttp://www.karcher.ca/CCE/HD%20- %20HDS%20Web%20Pages/Features/Powe rNozzle%20Spray%20Others.jpg Source: http://www.acme- fab.com/html_640/PROD_Monorail-washer.htmlhttp://www.acme- fab.com/html_640/PROD_Monorail-washer.html

21. 21 Aqueous Cleaning Inputs/Outputs Can you think of mathematical models for estimating these inputs/outputs for a closed-loop system?

22. 22 Generic Process Map of an Aqueous System Add chemicals and electricity to wastewater treatment

23. 23 Summary Main Points Showed how to estimate environmental loads of straight turning operation Similar approach should be applicable to other manufacturing processes (e.g., milling, cleaning, etc.) By estimating environmental loads & impacts a process engineer can (quantitatively) tradeoff cost, quality and productivity objectives and make better process planning decisions

24. 24 References 1.Sutherland, J.W. and Gunter, K.L., 2001, "Environmental Attributes of Manufacturing Processes," in Handbook of Environmentally Conscious Manufacturing, C.N. Madu, Kluwer Academic Publishers, pp. 293-316. 2.Skerlos, S.J., 2005, "Prevention of Metalworking Fluid Pollution: Environmentally Conscious Manufacturing at the Machine Tool, under peer review for textbook," in Handbook of Environmentally Conscious Mechanical Design - Volume 2: Environmentally Conscious Manufacturing, John Wiley & Sons.