Design a condenser for the following duty: 45,000 kg/h of mixed light hydrocarbon vapors to be condensed. The condenser is to operate at 10 bar. The vapor will enter the condenser saturated at 60 °C and the condensation will be complete at 45 °C. The average molecular weight of the vapor is 52. The enthalpy of the vapor is 596.5 kJ/kg and the condensate 247.0 kJ/kg. Cooling water is available at 30 °C and the temperature rise is to be limited to 10 °C. Plant standards require tubes of 20 mm o.d., 16.8 mm i.d., 4.88 m (16 ft) long, of admiralty brass. The vapors are to be totally condensed and no subcooling is required.