1. Elroy is Here to Stay

2. …A few words about UNIFAC… Interaction parameters for VLE ■ Fredenslund A, Gmehling J, Rasmussen P. 1977. Vapor- Liquid Equilibria Using UNIFAC. Elsevier, Amsterdam. ■ Hansen HK, et sl. 1991. Ind. Eng. Chem. Res. 30:2352–2355 ■ Wittig R, et al. 2003. Ind. Eng. Chem. Res. 42:183–188 Interaction parameters for LLE ■ Magnussen T, et al., HK, et sl. 1981. Ind. Eng. Chem. Fund. 20:331–339 Interaction parameters for heats of mixing ■ Dang D, Tassios DP. 1986. Ind. Eng. Chem. Process Des. Dev. 25:22–31

3. Interaction parameters (for VLE) Smith et al. 1996 Poling et al. 2001

4. CH 3 OH + H 2 O Soup of CH 3, OH and H 2 O groups Soup of CH 3 OH and H 2 O groups (molecules) CH 3 OH H2OH2O CH 3 OH H2OH2O H2OH2O H2OH2O

5. Design Project: Polylactic Acid Preliminary design and economic analysis for a plant producing 100 million lb/yr of lactic acid from a feed stream of corn steep liquor. Technical and economic aspects of design Procedural aspects of course Haven’t I seen this somewhere before? Report tips

6. Technical and economic aspects of design Advantages of polylactic acid Seriously cool biodegradable thermoplastic polymer.

7. Feed: corn steep liquor Steeping First step in wet corn milling 1–2 days at ~125 °F in dilute sulfurous acid solution Soften kernel, breaks down proteins, removes some soluble components End product of steeping is light steep water (LSW). Contains ~6% of dry weight of grain. 35–45% protein good for feed supplements LSW is evaporated to produce corn steep liquor (CSL). Dry solids content 30–55 g/L. This is feed for our process.

8. Process Holding tank(s) DP1 DP2 DP3

9. Optical isomers of lactic acid For design project, pretend as if L -isomer is the only one that exists. Can use D -properties.

10. Fermentation Composition of feed, etc. Biomass is acid-resistant bacteria Carried out batch at ~47 °C ComponentAmt. or conc. CSL (36 wt. % dry solids)12 vol. % Glucose90 g/L Calcium carbonate35 g/L Tween® 801 g/L Bacterial cells???

11. Kinetics, etc. Modified Monod equation pH Controls distribution between unionized form (lactic acid) and ionized (lactate) Tradeoffs in choosing number and size of fermentation tanks Decision Point 1

12. Cell separation / filtration Must be acknowledged in your flow sheet and mass balances, but does NOT have to be considered in detail Holding tank downstream of fermentation Needed to maintain continuous feed for the liquid extractor; size should be chosen carefully

13. Liquid extraction Do we need to talk about partitioning equilibria with ionizable groups? YES Do we need to talk about liquid extraction? YES A few comments now… Choice of solvent Light solvent (triethyl amine, butanol, octanol) Heavy amine (trioctyl amine, Alamine 336) Less detail in design: solvent flow rate, number of ideal stages Solvent flow rate affected by both extraction and distillation Decision Point 2

14. Distillation Components: lactic acid, extraction solvent, water 2 schemes depending on extraction solvent Possible water in extract makes this a ternary system S LA LA S S LA LA S

15. Recycle You should consider this element carefully in developing your process flow sheet Heat integration Elroy looks VERY kindly on processes exhibiting at least some degree of energy integration. Elroy frowns VERY strongly upon processes without any energy integration.

16. Required level of detail in technical design Fermenters A rigorous solution of the kinetic equations must underpin your fermentation reactor design. You must decide vessel number and size based on reactor residence time, factoring in the required time-average product flow rate, and the necessity of emptying, cleaning and charging fermenters between batches. This decision must be reported by 7 March (Decision Point 1). You must also define in detail how the fermenters will be heated or cooled to maintain the stated operating temperature.

17. Distillation You must develop a detailed design of the distillation column specifying reflux ratio and boilup ratio; temperature, pressure and composition of feed, distillate and bottom product streams; column height above feed and below feed, and column diameter; type of packing or trays; and thermal duty and heat transfer area for reboiler and condenser. Calculations can be made with UniSim. However, you must check carefully the properties of L -lactic acid, and augment them as necessary. Even if you use UniSim, you must also prepare a McCabe-Thiele diagram that explains your design.

18. Heat exchangers Determine and state thermal duty, heat transfer area, temperature and pressure of input and output streams, and type of heat exchanger. Fluid lines Your design must include sizes of all lines between units (must be standard sizes), and pump selection and power for each line. These specifications must be reported by 8 April (Decision Point 3).

19. Flow sheet Your completed design (and in particular, report) must contain a neat, computer-generated, detailed flow diagram. It should resemble Towler and Sinnott’s Figure 2.8 (p. 39). It may not be a UniSim flowsheet.

20. Streams must be labeled, with information about each stream (temperature, pressure, phase, composition) tabulated below by number. Information must be given in units customary among engineers in this country (not Planet X on the galactic rim), i.e., flow rates in lb/h or kg/h, pressures in psi or kPa, temperatures in °F or °C, dimensions in ft or m, and pipe sizes in in. Although you might use other units in calculations, they must be converted into acceptable units in your final presentation. Also, you should retain extra significant figures in order not to let round-off error corrupt your calculations. However, you should ultimately report only a reasonable number of digits. Net: a flow rate expressed as, e.g., 1.344789002 × 10 8 g/week WILL NOT FLY with Elroy or any of your project supervisors.

21. Givens (a) Materials available CSL (36 wt. % solids) Glucose Calcium carbonate Tween® 80 Bacterial cells (b) Services available Steam, 150 psig, saturated: $15 / 1000 kg Cooling water, 60 psig, 30 °C supply, 40 °C return: $0.20 / 1000 gal Process water (chilled), 60 psig, 15 °C: $1.50 / 1000 gal Electricity: $0.06 / kWh Wastewater treatment: $3.00 / 1000 gal

22. (c) Product specification Lactic acid, mole fraction ≥ 99.9%, ≤ 0.01% solvent, sells for $0.90/lb (d) On stream time Assume 8000 hours / year

23. Economic analysis Assume 20-year project life, 6% annual effective interest rate, 40% tax rate. Results and criteria specifically to be addressed in your final report are: fixed and working capital investment, manufacturing cost, and revenue; return on investment (minimum acceptable 15% after income tax), and net present value. Base capital cost estimates mainly on tables in Towler and Sinnott (especially Table 7.1 (pp. 314–317) and Table 7.2 (pp. 322–324)), which yield reasonable study estimates. Do NOT expend effort contacting actual vendors for quotations on specific pieces of equipment.

24. As with process stream variables, figures from the economic analysis should be reported with a reasonable number of digits, especially as your cost estimates will be subject to ±30% error or more. In other words, report e.g. a net present value as $12,400,000, not $12,364,078.92.

25. …just reminding us that Elroy is here to stay…

26. Procedural aspects of course Industrial participants Paul Ameis (VanDeMark Chemical) Dr. David Courtemanche (Dupont) Dr. Rich Fickelscherer (Falconeer) Dr. Vasilis Papavassiliou (Praxair) Dr. William Schatmach (Praxair)

27. Regular meetings and progress reports Meetings with project supervisors Schedule Sign-up sheets posted on MN’s office door; sign up early Must talk with four different supervisors during semester All members of group must be present at meeting (grade penalty for absence) Bring questions Meeting #Week ofGroup meetings with 008 FebruaryHutch 122 FebruaryAmeis, Fickelscherer, Papavassiliou, Scharmach 207 MarchAmeis, Fickelscherer, Papavassiliou, Scharmach 328 MarchAmeis, Fickelscherer, Papavassiliou, Scharmach 418 AprilAmeis, Fickelscherer, Papavassiliou, Scharmach

28. Progress reports Schedule & contents Must be received in time for supervisors to have a look before meeting. Also bring paper copy to meeting. ReportEmail due date Mtg. due date Contents Interim #008 Feb. by 4:00 pm Bring to Mtg. #0 Introduction and literature review; solutions of acid dissociation equilibrium problems posed Interim #122 Feb. by 4:00 pm Bring to Mtg. #1 Preliminary definition of process streams and units; preliminary flow sheet Interim #207 Mar. by 4:00 pm Bring to Mtg. #2 Flow sheet with all mass and energy balances completed; analysis of production costs and revenues; Decision Point 1 — number and size of fermentation tanks decided Interim #328 March by 4:00 pm Bring to Mtg. #3 Preliminary economic evaluation of flow sheet; Decision Point 2 — solvent flow rate in liquid extraction decided Interim #418 April by 4:00 pm Bring to Mtg. #4 Provisional final flow sheet with all mass and energy balances completed; designs as requested for all units; provisional final economic evaluation; Decision Point 3 — line sizes determined Final report2 May by 4:00 pm Final report

29. Composition of grade for design project Component% of grade Report #0 2 Meeting #0 (preparedness and quality of discussion) 1 Report #1 3 Meeting #1 (preparedness and quality of discussion) 2 Report #2 3 Meeting #2 (preparedness and quality of discussion) 2 Report #3 3 Meeting #3 (preparedness and quality of discussion) 2 Report #4 3 Meeting #4 (preparedness and quality of discussion) 2 Final Report67 Final Presentation 5 SEAS Senior Design Expo 5

30. Calendar

31. Haven’t I seen this somewhere before? Yes I have… several times! CE 212 fall 2013: Extraction of LA from water with 1-octanol

32. CE 304 spring 2014: VLE of LA + 1-octanol mixtures

33. CE 317 fall 2014: Pipe flow and pumping of LA solution

34. CE 329 fall 2014: Batch fermentation kinetics based on Monod’s equation Problem was due 13 October 2014

35. CE 318 spring 2015: Murphree efficiency in distilling mixtures of LA and 1-octanol

36. CE 407 spring 2015: Multistage countercurrent extraction of LA from water with 1-octanol

37. CE 427 fall 2015: LA process safety Also bioreactor kinetics and deduction of acid conc. from pH!

38. Project and report tips Energy recovery OK to condense or boil streams, with understanding that pinch analysis cannot be strictly applied Figures and tables On “page of floats” near point of reference

39. Quality of figures

40. Quality of tables

41. Why present material given to you, or that is available in textbooks?

42. …just reminding us that Elroy is here to stay…