Continuous fractionation: Savarit-Pouchon method 9.10 An acetone-water solution containing 25 wt % acetone is to be fractionated at a rate of 10 000 kg/h at I sid atm pressure, and it is planned to recover 99.5% of the acetone in the distillate at a concentration of 99 wt %. The feed will be available at 26.7"C (80 F) and will be preheated by heat exchange with the residue product from the fractionator, which will in turn be cooled to 51.7"C (125*F). The distilled vapors will be condensed and cooled to 37.8 C (125'F) by cooling water entering at 26.7'C and leaving at 40.6'C. Reflux will be returned at 37.8"C, at a reflux ratio Lo/ D = 1.8. Open steam, available at 70 kN/m, will be used at the base of the tower. The tower will be insulated to reduce heat losses to negligible values. Physical property data are given in Prob. 9.4. Determine; (a) The hourly rate and composition of distillate and reflux. (b) The hourly condenser heat load and cooling water rate. (c) The hourly rate of steam and residue and the composition of the residue. (d) The enthalpy of the feed as it enters the tower and its condition (express quantitatively). () The number of theoretical trays required if the feed is introduced at the optimum location. Use large-size graph paper and a sharp pencil. Ans.: 13.1