Abstract:
Fossil fuel is the dominant energy source worldwide accounting
for 80 % of total energy sources, 18 % of it is being used for electricity
generation which made the search for improvement opportunities in
order to optimize the design and operation condition essential. The
present work aims to analyze the performance of Garrri 4 power plant
(110 MW); a sponge coke fired circulating fluidized bed power plant in
order to define improvement opportunities magnitude and location. The
system was analyzed using Energy and exergy analysis at three different
loads 29.32 MW, 45MW and 47 MW in term of key performance
parameter. The energy analysis revealed the boiler as the main source of
exergy destruction accounting for 85.59%, 85.29 and 75% from the total
exergy destruction, and the heaters as having the highest exergetic
efficiency ranging from (73.25- 99.6)% (74.6 - 95.29)% and (55- 98.9)%
followed by the steam Turbine having 69.27%,72.29% and 76.10% all for
the sited loads respectively. A general improvement in the plant
exergetic efficiency is observed when shifting toward the plant’s rated
load from 21.79%, 23.72% till 26.27% for the studied loads respectively
accompanied by a slight reduction in exergy destruction associated with
the generation of 1MW of electricity from 10.92 MW, 9.97 MW and 9.85
MW respectively.
