Problem 8.2: Use the data for the system methanol-ethanol (from the previous problem) to design a separation process that takes a mixture with 20% methanol and produces a stream that contains 90% methanol by continuously flashing the vapor stream until the required purity is reached (the liquid streams are not recycled). The process is to be operated at 1 bar with a ratio V/L = 0.5 in all flash separators.
a) How many flash separators are needed?
b) Calculate the percentage of methanol recovered in the 90% stream relative to the methanol in the feed.
c) Change the vapor liquid ratio to V/L = 0.75 and repeat parts a and b.
d) Your boss has asked you to recommend a value for the vapor, liquid ratio V/L. What is your recommendation?