Power plants – Combustion products used as motive fluid
Patent
1998-03-23
2000-04-04
Thorpe, Timothy S.
Power plants
Combustion products used as motive fluid
60 39511, 60 39512, 60728, F02C 100
Patent
active
060446404
DESCRIPTION:
BRIEF SUMMARY
TECHNICAL FIELD
The present invention refers to a process and an installation for cooling combustion air of gas turbines.
Nowadays, the use of gas turbine for the generation of electric power is considerably increasing worldwide, since not all countries have abundant water resources and furthermore the technology of nuclear power station is very expensive and complicated.
Gas turbines are extremely sensitive to the ambient air temperature. The higher the temperature of the feed air for combustion, the lower the maximum power produced by the turbine will be, and also its efficiency will be lower too, causing higher fuel consumption per KW of electric power produced. Generally, this problem increases in the summer months, exactly when the power consumption is higher.
Due to the variations of power with respect to the temperature of the air for combustion, a dry bulb temperature of 15.degree. C. was established by the ISO international norms, for normalization of the nominal values of gas turbine power. Taking this reference as a basis, it has been found that the power of a turbine operating at 35.degree. C. may be reduced by as much as 17%.
PRIOR ART AND SHORTCOMINGS OF THE PRIOR ART
Thus, in order to increase the efficiency of the turbine, combustion air-cooling systems are employed, which consists basically of the following:
a) a common cooling system with compressors (reciprocating, screw or centrifugal) either provided or not with a (water or ice) thermal storage system;
b) absorption units, employing either steam or hot fluids as energy source for obtaining the cooling effect.
In the combustion air-cooling systems that have thermal storage, ice is produced during the night using a portion of the power of the turbine itself, storing the ice in appropriate tanks. On the next day the ice is used in the peak hours to cool the turbine combustion air, in order to increase its efficiency and power.
The first disadvantage of the existing technology for combustion air cooling system is the fact that the initial installation cost is high.
Another disadvange consists of the fact that the operation cost of these systems is quite high, since it consumes energy from the turbine itself, which will be only partially recovered. In such systems a great loss of energy occurs due to the inevitable moisture condensation while cooling the air. The energy required for the condensation of the air moisture is in most cases higher than that necessary to the reduction of the air temperature, i.e., more than a half of the consumed energy is used without any useful effect.
Document U.S. Pat. No. 5,203,161 describes a method and arrangement for cooling air fed to gas turbines and presents, according to the figure on the cover page, an absorption chiller (486) for initial cooling of the air in the water spray cooler (480); an absorption chiller (451) for cooling the liquid desiccant contactor (440); a vapor compression chiller (430) for cooling the air in the chiller coil (425) and a liquid desiccant system comprising lines (458, 460, 462) and a desiccant regenerator (459). The first disadvantage of this arrangement consists in the fact that the absorption chiller (486 and 451) and the vapor compression chiller (430) need external energy to carry out their functions. Another disadvantage is the fact that the arrangement presents a complicated system of liquid desiccant.
Document U.S. Pat. No. 5,193,352 describes an apparatus and method for cooling air of a turbine (20) which actuates a generator (19). As in the prior cited document, this apparatus also presents the disadvantage that cooling of the air is carried out by devices, such as IMP-ice making plant (62), DCC-direct contact chiller (12) and TSU-thermal storage unit (60), which need external energy to carry out their functions.
Document U.S. Pat. No. 3,844,737 describes a desiccant system for an air-conditioning system, which comprises a heater for dehumidifying the air, i.e., the device presents the disadvantage that it needs external energy to carry out its function.
Docu
REFERENCES:
patent: 3349248 (1967-10-01), Garnier
patent: 3785145 (1974-01-01), Amann
patent: 3844737 (1974-10-01), Macriss et al.
patent: 4426853 (1984-01-01), Mitani et al.
patent: 5148670 (1992-09-01), Birch et al.
patent: 5193352 (1993-03-01), Smith et al.
patent: 5203161 (1993-04-01), Lehto
Journal of the Institution of Engineers (India), vol. 57, No. me-1, Jul. 1976, India, pp. 266-272, XP002005497, V. Charan, et al.: "Use of Dehumidifier and Heat Exchanger with an Evaporative Cooler."
Gartenberg Ehud
Thorpe Timothy S.
LandOfFree
Process and installation for cooling air does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Process and installation for cooling air, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process and installation for cooling air will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-354966