Concentrated fermentation liquid containing 20% (w/w) gluconic acid from an evaporator has a flow rate of 2000 kg/h and a temperature 90 °C. It needs to be cooled to 6 °C in a heat exchanger with cooling water. The cooling water has a flow rate 2700 kg/h and an initial temperature 2 °C. If the cooling water leaves the heat exchanger at 50 °C, what is the rate of heat loss from gluconic acid solution to the surroundings? Assume the heat capacity of gluconic acid is 0.35 cal/g-°C^-1.
(a) 69390.84 kJ/h
(b) 65780.56 kJ/h
(c) 67890.67 kJ/h
(d) 65432.10 kJ/h
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Question is from Energy Balance Numericals Without Reactions in section Energy Balance of Bioprocess Engineering
