2000 kg/h of milk is sterilized in a steam infusion sterilizer. The
milk is heated to 145 ℃ by introducing it into the steam infusion chamber H and then is cooled quickly by flashing in the flash vessel F. The vapor that flashes off in the vessel F is condensed in the condenser C by direct contact of the vapor with cooling water. To avoid dilution of the milk, the pressure in the vessel F must be such that the rate at which vapor flashes off in the vessel F is equal to the steam that is added in the vessel H. Calculate the cooling water flow rate in the condenser that will give the required pressure in the flash vessel. The following data are given: The temperature of the milk at the inlet of H is 40 ℃, the temperature of the cooling water at the inlet of the condenser is 20 ℃, the steam introduced into the chamber H is saturated at 475.8 kPa pressure, and the heat capacity of the milk is 3.8 kJ/kg ℃ at the inlet of the infusion chamber and 4 kJ/kg ℃ at the exit of the infusion chamber.