The use of a Steam condenser in a power plant is to improve the efficiency of the
power plant by decreasing the exhaust pressure of the steam below atmosphere.
Another advantage of the condenser is that the steam condensed may be recovered
to provide a source of good pure feed water to the boiler and reduce the water
softening capacity to a considerable extent. A condenser is one of the essential
components of a power plant.
Functions of Steam Condensers
The main purposes of the condenser are to condense the exhaust steam from the
turbine for reuse in the cycle and to maximize turbine efficiency by maintaining
proper vacuum.
As the operating pressure of the condenser is lowered (vacuum is increased), the
enthalpy drop of the expanding steam in the turbine will also increase. This will
increase the amount of available work from the turbine (electrical output).
Why Air-Cooled Steam Condensers?
a. Water Usage: Air cooled steam condensers use air, not water, as the cooling
medium, allowing economic criteria to determine plant design and location, rather
than availability of water.
b. Thermal Pollution: Air-cooled steam condensers eliminate thermal pollution of
rivers, lakes and streams by discharging heat directly to the atmosphere.
c. Chemical Pollution: Because air cooled steam condensers do not use Evaporative
cooling, they eliminate requirements for disposal of large quantities of chemically-
treated water.
d. Visual Pollution: Water vapor plumes that rise into the air from evaporative coolers
can cause ground fog and ground ice formation, both of which are potential
hazards. Air cooled steam condensers eliminate these conditions.
e. Sitting Flexibility: Environmentally compatible air cooled steam condensers
eliminate water dependence, chemical effluent disposal, thermal pollution and
plume formation to simplify the permitting process and allow maximum flexibility
in plant sitting.
Introduction of Air Cooled Steam Condenser
Due to the decreasing availability and rising cost of cooling Water, dry-cooling towers
or direct air-cooled condensers (ACC’s) are increasingly employed to reject heat to
the environment in modern power plants incorporating steam turbines. Unfortunately,
with an increase in the ambient temperature, the effectiveness of these cooling
systems decreases resulting in a corresponding reduction in turbine efficiency. The
3. Air Cooled Steam Condenser
