integration of solid oxide fuel cells and ... - Ea Energianalyse

3.14 Cooling Tower - TOWER
3.14. Cooling Tower - TOWER
Removing heat (at a temperature not too far from the ambient temperature)
to the surrounding air can be somewhat difficult, expensive and
energy consuming (and perhaps water consuming). Three popular solutions
exist:
air,o
air,o
air,o
DRY
WET
SEMI
w,add
w,add
w,o
FAN
air,mp
air,i
w,i
w,o
FAN
air,mp
air,i
w,i
w,o
FAN
air,mp
air,i
w,i
Figure 3.16: The three variants of the Cooling Tower component. w = water, i = inlet, o = outlet,
mp = midpoint (after fan at the air side) and w.add = water addition.
• A Dry Cooling Tower, which only consumes power for driving
a fan to send ambient air over tubes containing the fluid to be
cooled. A dry cooler can, however only cool down the fluid to a
temperature above the ambient temperature.
• A Wet Cooling Tower, which utilizes the enthalpy of evaporation
of water for cooing the fluid. The water and air is in direct contact,
which increases the heat transfer. Furthermore, by using this
component it is possible to cool down the fluid to below ambient
temperature. A wet tower has the advantage, that it consumes
(less) power for driving a fan than a dry tower, since a smaller air
flow is needed, but on the downside it has a water consumption to
make up for the water lost in evaporation.
• A semi-wet Cooler mixing the two types above by spraying a water
mist over the tubes of the dry cooling tower to use the enthalpy of
evaporation. This has the advantage that more water can be added
during hot weather, while the cooler can run in dry cooling mode
during cold weather. But since the fluid inside the tubes and the air
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