Double-Effect Evaporator with Reverse Feed. A feed rate of 20410 kg/hr of 10 wt % NaOH solution at 48.9 °C is being concentrated in a double-effect reverse-feed evaporator to produce a 50% solution. Saturated steam at 178.3 °C is fed to the first evaporator and the pressure in the second effect is 10.34 kPa abs. The heat-transfer coefficient for each effect is assumed to be 2840 W/m²-K. Calculate the heat-transfer area, the steam consumption rate, and the steam economy.

Double-Effect Evaporator with Reverse Feed. A feed rate of 20410 kg/hr of 10 wt % NaOH solution at 48.9 °C is being concentrated in a double-effect reverse-feed evaporator to produce a 50% solution. Saturated steam at 178.3 °C is fed to the first evaporator and the pressure in the second effect is 10.34 kPa abs. The heat-transfer coefficient for each effect is assumed to be 2840 W/m²-K. Calculate the heat-transfer area, the steam consumption rate, and the steam economy.

Principles of Heat Transfer (Activate Learning with these NEW titles from Engineering!)

8th Edition

ISBN:9781305387102

Author:Kreith, Frank; Manglik, Raj M.

Publisher:Kreith, Frank; Manglik, Raj M.

Chapter9: Heat Transfer With Phase Change

Section: Chapter Questions

Problem 9.27P

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