Recovery and processing of various oils are important elements of the agricultural and food industries. For example, soybean hulls are removed from the beans, which are then flaked and contacted with hexane. The hexane extracts soybean oil and leaves very little oil in the residual solids. The solids are dried at an elevated temperature, and the dried solids are used to feed livestock or further processed to extract soy protein. The gas stream leaving the dryer is at 80°C, 1 atm absolute, and 50% relative saturation.
(a) To recover hexane, the gas leaving the dryer is fed to a condenser, which operates at 1 atm absolute. The gas leaving the condenser contains 5.00 mole% hexane and the hexane condensate is recovered at a rate of 1.50 kmol/min.

Calculate the condenser temperature and the required flow rate of fresh nitrogen to the dryer in standard cubic meters per minute (SCMM).
(b) In an alternative arrangement, the gas leaving the dryer is compressed to 10.0 atm and the temperature simultaneously is increased so that the relative saturation remains at 50%. The gas then is cooled at constant pressure to produce a stream containing 5.00 mole % hexane. Calculate the final gas temperature and the ratio of volumetric flow rates of the gas streams leaving and entering the condenser. State any assumptions you make.
(c) What would you need to know to determine which of processes (a) and (b) is more cost-effective?

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Na. high T N, 80°C, 1 atm CH14 (s, = 50%) N2 CH14 (V)(5 mole%) DRYER CONDENSER (I atm) Wet solids 1.5 kmol CH(0ymin Dry solids