A feed of 4,535 kg/h of a 2% wt. salt solution at 38 C enters continuously...

A feed of 4,535 kg/h of a 2% wt. salt solution at 38 C enters continuously a single-effect evaporator and is being concentrated to 3% wt. The efficiency of the evaporator is at 85%. The evaporator is at atmospheric pressure and the area of the evaporator is A= 69.7 m2. Saturated steam at 110 C is supplied for heating (90% quality). Since the solution is dilute, it can be assumed to have the same boiling point as water. The heat capacity of the feed can be taken as Cp=4.10 Kj/kg C. If the evaporator is operating at atmospheric pressure 101.3 kPa (absolute). Calculate
1. Amount of steam needed (kg/h) per one kg/h of water removed
2. Calculate overall heat transfer coefficient, U. if the heat exchanger works in a counter-current flow

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Amanda K answered 5 months ago

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