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

E. OPTIMIZATION GRAPHS
E.1.3
Towers
The influence of the Closest Approach Temperature Difference on the
two different types of towers is now investigated.
E.1.3.1 ∆ T,min,Tower
Figure E.5
The COP ABS,f uel (blue curve in figure E.5) is heavily dependent on
the ∆ T,min when the DRY Tower is used because a large ∆ T,min,Tower
will give a large absorber and condenser temperature. The electrical
efficiency of the system (black curve) raises a little when ∆ T,min,Tower is
increased, but that is merely due to lower FAN power consumption when
the absorption cooling unit becomes less efficient and this way needs less
low quality heat removed.
For the WET Tower the COP ABS,f uel (figure E.6A) is unaffected by
the ∆ T,min . This is because the (somewhat simple) model of the wet
tower only uses the air inlet conditions and tower (wet bulb) efficiency to
determine the water outlet temperature. So the water outlet temperature
is not affected by the ∆ T,min (hence COP is unaffected).
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