You work for a company that synthesizes pharmaceutical intermediates. A solvent acetone (ACE) is used in the purification of the drug. Recently 100 drums (200 liters per drum) of pure acetone were accidentally mixed with 10 drums of waste solvent containing 40 wt.% methanol (MET) and 60 wt.% 2-propanol (IPA). The plant needs more acetone for purification of the drug, and it will take two weeks for a new shipment to arrive. The drug is very profitable, and management wants to keep the operation running at full capacity. Your supervisor wants to know if a flash process can be quickly developed to remove the acetone from the MET/IPA mixture. The pharmaceutical chemist says if the acetone is >95 wt.% pure they can still use it. Therefore, we would like your team to design an isothermal flash process for the partial removal of acetone from the mixture. 1) How much (if any) of the acetone can be recovered with a purity which meets the pharmaceutical chemist's specification? 2) Please provide the feed conditions (composition, temperature, pressure, rate) and the resulting product stream conditions. Hint: Use Aspen Plus to solve this problem, provide table(s) or figure(s) with assumed conditions and results to support your answers and calculations. Please name your feed stream "FEED_initials" with your initials inserted. I mentioned above that this uses Aspen Sensitivity. This tool is really handy for looking at the influence of variables upon outputs. You could run 10+ unique simulations varying pressure, temperature etc. Instead, the Sensitivity tool collects even more data in a single "run". Please practice using the tool. To start this problem, you'll want to define a flowrate - it's a bit arbitrary. It would depend on the size of your equipment but one way to think about it is: how long should this take? Some managers might want it done in one shift, realistically that means about 4 h of separation time because your operators need time for set up and shut down. If the plant runs 24 h, the manager might want 10 h of separation time. You decide. You'll also need to specify an initial pressure and temperature. You might look at the Txy and Pxy diagrams in Properties to make your initial guess. As long as you're in the 2-phase envelope it shouldn't matter too much what you choose because "sensitivity" will explore a broader range of variables. Think about how to define the output of the sensitivity analysis.

ISBN: 9781259696527

Author: J.M. Smith Termodinamica en ingenieria quimica, Hendrick C Van Ness, Michael Abbott, Mark Swihart

Publisher: McGraw-Hill Education