Generally operating cost for Air Cooled Heat Exchanger (ACHE) is less than the same of water-cooled heat exchanger (WCHE). Operating cost of WCHE includes cost of make-up water for the cooling water, power required for the cooling tower fans and for the circulating pump, cooling tower maintenance, etc. while operating cost of ACHE includes cost of power consumed by fan. Day by day cost of water increases and hence the difference in operating cost between WCHE and ACHE increases.
Inlet temperature of water to cooling tower (or outlet temperature of cooling water from heat exchanger circuit) should not be greater than 600C otherwise it creates the scale formation and also affects the material of construction of cooling tower. While for air there is no limit for temperature.
Fouling or scale formation does not take place with air cooling.
Since water is not used as the cooling medium, the disadvantages of using water are eliminated.
Eliminates high cost of water including expense of treating water.
Thermal or chemical pollution of water resources is avoided.
Installation is simplified due to elimination of coolant water piping.
Location of the air-cooled heat exchangers is independent of water supply location.
