help on Separation Homework.

The Problem Current methods for biofuel production focus on a single product such as corn-derived ethanol or algae-derived diesel fuel. The next generation of processes based on plant-derived lignocellulosic biomass are envisioned to operate as “biorefineries” rather than focusing on a single product. One way to diversify products is to use a variety of fermentation organisms with different product profiles. In this project, you will explore methods to separate products of the reaction of fermentation-derived ethanol and n-butanoic acid to produce ethyl butyrate. Butanoic acid has an extremely unpleasant smell to humans, but ethyl butyrate has a pleasant fruity smell similar to pineapple and is used as a solvent and in the food and fragrance industries. The produce from a catalytic reactor consists of an equimolar mixture of 25 kmol/h of each of four components: ethanol, n-butanoic acid, water, and ethyl butyrate. You are to design a separation train to accomplish three things: (1) recover 99% of the ethyl butyrate at 99% purity, (2) remove at least 99.9% of the water from the process, and (3) recover at least 95% of both ethanol and butanoic acid for recycling to the reactor. You do not need to account for this recycling (just to produce either a mixture of ethanol and butanoic acid or two pure streams). Your goal is to develop a moderately detailed design in which all separation units are specified, thermodynamic models are described for the mixtures, and operating conditions (temperatures, pressures, flowrates and numbers of stages) are determined. Design Rules 1. You need to choose thermodynamic models and provide evidence that they are accurate for your mixtures to the extent that you are able (use handbooks, data compilations, journal articles, etc.). 2. You must state and justify the assumptions that you make for the calculations on each unit. For instance, you need to explain why constant molal overflow is OK before doing a McCabe-Thiele calculation. 3. If a rule of thumb is needed, external reflux ratios can be set to 25% higher than the minimum required. 4. You determine and specify number of stages, feed location and any other process parameters of all units. Be on guard for excessively large or small numbers. 5. You should make every effort to completely regenerate and recycle any components that you add (including solvents and adsorbents), while accounting for necessary makeup streams. 6. Detailed economic calculations are not needed, but if multiple options are explored or optimization is performed, the capital and operating expenses should be compared. The final capital and operating costs of the process should also be provided. Report Required 1. Projects must be completed by your ASPEN groups. 2. Grading will be based on the attached evaluation form. 3. Final report a. Main text will be limited to 12 pages including figures, with additional calculations or figures in Appendices. Spacing should be 1.5 with 12 pt Times New Roman or 11 pt Arial, Courier or similar font. b. Only one report per group c. Contents i. Title page ii. Executive summary (or abstract – include key results) iii. Introduction (background about what is the problem and why are you designing this) iv. Design calculation methodology (assumptions and justifications, thermodynamic model, etc.) v. Results and Discussion (what did you find worked, were there any complications, what are heating/cooling requirements, etc.) vi. Conclusions (be concise and only describe final outcomes) vii. References cited viii. Appendices: Figures, tables, summary flowsheets, sample calculations. Be sure that figures are legible, clear, and have descriptive captions.