# Calculating Temperature, Water Evaporation, and Heat in a Power Plant Cooling Situation

In a nuclear power plant the cooling tower system must be run on a closed cycle. That is, the air exiting the tower passes over cooling coils to return it to its initial condition prior to reentering the tower. Air at 20 degrees C and 40% relative humidity enters the tower at a rate of 1.3 x 106 kg/sec. Water enters the tower at 50C and leaves at 25C. The water flow rate is 750,000 kg/sec. Saturated air exists the tower and passes over cooling coils which returns it to 20C and 40% relative humidity. Water at 22C condenses out of the air. Determine:

A) The temperature of air leaving the tower

B) Amount of water evaporating in kg/sec.

C) The heat removed by the cooling coils in kW

#### Solution Preview

...mass flow rate of water= 750,000 kg /sec

Cool Air: at inlet Ta1=20 c

at out let Ta2 = ?

Mw = mass flow rate of water= 1.3 *106 kg /sec

Heat removed by cooling coils ...