The ABE biochemical process makes acetone, n-butanol, and ethanol by an anaerobic, submerged, batch fermentation at 30C of corn kernels, using a strain of the bacterium Clostridia acetobutylicum. Following fermentation, the broth is separated from the biomass solids by centrifugation. Consider 1,838,600 L/h of clarified broth of S.G. = 0.994, with a titer of 22.93 g/L of ABE in the mass ratio of 3.0:7.5:1.0. A number of continuous bioseparation schemes have been proposed, analyzed, and applied. In particular, the selection of the first separation step needs much study because the broth is so dilute in the bioproducts. Possibilities are single-stage flash, distillation, liquid–liquid extraction, and pervaporation. In this exercise, a single-stage flash is to be investigated. Convert the above data on the clarified broth to component flow rates in kmol/h. Heat the stream to 97C at 101.3 kPa. Use a process simulator to run a series of equilibrium-flash calculations using the NRTL equation for liquid-phase activity coefficients. Note that n-butanol and ethanol both form an azeotrope with water. Also, n-butanol may not be completely soluble in water for all concentrations. The specifications for each flash calculation are pressure = 101.3 kPa and V=F, the molar vapor-to-feed ratio. A V=F is to be sought that maximizes the ABE in the vapor while minimizing the water in the vapor. Because the boiling point of n-butanol is greater than that of water, and because of possible azeotrope formation and other nonideal solution effects, a suitable V=F may not exist.