A single effect evaporator is used to produce 30 kg per minute of thick liquor contains...

A single effect evaporator is used to produce 30 kg per minute of thick liquor contains 35 % by Weight of NaOH . The aqueous NaOH solution enters into the evaporator contains 8 % of NaOH by Weight . 6942 . 8 kg per hour of steam is used is heating medium and the vapor space pressure is maintained at 120 mmHg . Assume heat transfer coefficient 0 . 416 kcal / s . m * . °C , enthalpy of feed = 117 . 15 kJ / kg , enthalpy of product = 55 kcal / kg and latent heat of steam is 2202 . 58 kJ / kg .

a ) . Calculate capacity of the evaporator .

b ) . At what pressure the steam is supplied if the heat transfer area is 72 . 56 x 10 mm and BPR is 303K ? Assure the distance between liquid level and heat transfer surface in the evaporator is 180 cm ?

Expert Solution

Amanda K answered 7 months ago

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