Pinch technology has developed into a powerful tool for thermodynamic analysis of chemical processes and associated utilities, resulting in significant energy savings. Conventional pinch analysis identifies the most economical energy consumption in terms of heat loads and provides practical design guidelines to achieve this. However, in analyzing systems involving heat and power, for example, steam and gas turbines, etc., pure heat load analysis is insufficient. Exergy analysis, on the other hand, provides a tool for heat and power analysis, although at times it does not provide clear practical design guidelines. An appropriate combination of pinch and exergy analysis can provide practical methodology for the analysis of heat and power systems. The methodology has been successfully applied to refrigeration systems. This paper introduces the application of a combined pinch and exergy approach to commercial power plants with a demonstration example of a closed-cycle gas turbine (CCGT) system. Efficiency improvement of about 0.82 percent (50.2 to 51.02 percent) can be obtained by application of the new approach. More importantly, the approach can be used as an analysis and screening tool for the various design improvements and is generally applicable to any commercial power generation facility.

Issue Section:
Gas Turbines: Closed Cycles
Topics:
Closed-cycle gas turbines, Design, Exergy analysis, Pinch effect, Heat, Stress, Chemical processes, Energy consumption, Energy generation, Exergy, Gas turbines, Power stations, Power systems (Machinery), Public utilities, Refrigeration, Steam
1.
Kinney, C., and Wright, D. E., 1978, “Advanced Coal-Fueled Combustor/Heat Exchanger Technology Study,” Division of Power Systems, Department of Energy USA, Contract No. EF-77-C-01-2612.
2.
Dhole, V. R., 1991, “Distillation Column Integration and Overall Design of Subambient Plants,” PhD thesis, UMIST, Manchester, United Kingdom.
3.
Dhole, V. R., and Linnhoff, B., 1992, “Total Site Targets for Fuel, Co-generation, Emissions and Cooling,” presented at ESCAPE II conference, Toulouse, France; also Computers and Chemical Engineering, 1993, Vol. 17, Suppl., pp. s101–s109.
4.
Dhole, V. R., and Linnhoff, B., 1993, “Overall Design of Low Temperature Processes,” presented at ESCAPE III Conference, Graz, Austria; also Computers and Chemical Engineering, Vol. 18, Suppl., 1994, pp. S105–S111.
5.
Hall, S. G., 1989, “Targeting for Multiple Utilities in Pinch Technology,” PhD thesis, UMIST, Manchester, United Kingdom.
6.
Hall, S. G., Parker, S. J., Linnhoff, B., 1992, “Process Integration of Utility Systems,” presented at IEA workshop on Process Integration, Gothenburg, Sweden, organized by CADDET/CASU.
7.
Linnhoff, B., et al., 1982, “User Guide on Process Integration for the Efficient Use of Energy,” Institution of Chemical Engineers, Rugby, United Kingdom.
8.
Linnhoff
 
B.
, and
Ahmed
 
S.
,
1989
, “
Supertargeting: Optimal Synthesis of Energy Management Systems
,”
ASME Journal of Energy Resources Technology
, Vol.
111
, pp.
131
–
136
.
9.
Linnhoff
 
B.
, and
Dhole
 
V. R.
,
1992
, “
Shaftwork Targets for Low Temperature Process Design
,”
Chem. Eng. Sci.
, Vol.
47
, No.
8
, pp.
2081
–
2091
.
10.
Umeda
 
T.
,
Niida
 
K.
, and
Shiroko
 
K.
,
1979
, “
A Thermodynamic Approach to Heat Integration in Distillation Systems
,”
AIChE Journal
, Vol.
25
, No.
3
, pp.
423
–
429
.
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