JPH0472049B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a gas turbine power generation system that combines a gas turbine power generation device and an exhaust heat recovery boiler. (Prior Art) Conventionally, this type of system has been devised to extract electric energy and steam energy by combining a gas turbine power generator 101 and an exhaust heat recovery boiler 102, as shown in FIG. Simple open gas turbine power generation systems are well known and widely used in general industry. That is, in this system, the gas turbine power generation device 100 compresses the air that is taken in by the air compressor 106, guides the high-pressure air as combustion air to the combustor 107, and injects fuel into the combustion air. This generates high-pressure and high-temperature combustion gas, which is expanded by the gas turbine 108 to generate rotating shaft power, which is used to power the generator 110.
The gas turbine 10 is configured to extract electrical energy by driving the gas turbine 10.
Even in the exhaust heat recovery boiler 102 installed in the exhaust gas exhaust pipe 112 led from 8, the exhaust gas (generally
500° C.) to generate steam, and the steam energy is supplied to an appropriate load system from the steam supply pipe 113. (Problem to be Solved by the Invention) However, in such a system, due to the hydrodynamic characteristics of the air compressor 106, the continuous maximum output of the generator 110, that is, the rated output, depends on the intake air temperature and therefore the outside air temperature. It will be greatly affected. For example, when a 3 MW class gas turbine power generator is used at its rated output point, as shown by the solid line in Figure 3, the generator end output rapidly decreases as the outside temperature rises. In the winter, only about 80% of the output can be obtained. Therefore, even if you invest in equipment for 3MW output,
This means that only an average of 2.7MW of electricity can be obtained throughout the year, which is extremely uneconomical. The present invention has been made in view of these points, and provides a gas turbine power generation system that can always exhibit good power generation capacity without reducing the amount of power generation even when the outside air temperature is high as in summer. The purpose is to (Means for Solving the Problems) The present invention provides a gas turbine power generation system that combines a gun turbine power generation device and an exhaust heat recovery boiler, in which an air cooler is interposed in the intake pipe of the gas turbine power generation device. At the same time, a compression water cooler is connected to the gas turbine shaft of the gas turbine via a reduction gear mechanism, and cold water is circulated from the compression water cooler to the air cooler to cool the air supplied to the turbine generator. This is the basic structure of the invention. (Operation) The air taken into the gas turbine power generator is cooled by heat exchange with cold water circulating between the air cooler and the compression water cooler. Therefore, even when the outside air temperature is high, the intake air temperature becomes low, and a decrease in power generation output due to a rise in the outside air temperature is reliably avoided. As a result, the average amount of electricity consumed throughout the year increases. (Example) Hereinafter, the configuration of the present invention will be specifically explained based on the example shown in FIG. In the gas turbine power generation system shown in FIG. 1, 1 is a gas turbine power generation device, 2 is an exhaust heat recovery boiler, 3 is a compression type water cooler, and 4 is an air cooler. The gas turbine power generation device 1 compresses atmospheric air taken in through an intake pipe 5 with an air compressor 6, and guides the high-pressure air to a combustor 7 as combustion air.
Fuel is injected into the combustion air to generate high-pressure and high-temperature combustion gas, which is expanded by the gas turbine 8 to generate rotating shaft power, which is then transmitted via the reduction gear mechanism 9 by the gas turbine shaft 8a. It is configured to extract electrical energy by driving the generator 10. Further, an exhaust gas discharge pipe 12 is led from the gas turbine 8 to the chimney 11. The exhaust heat recovery boiler 2 is installed in the exhaust gas exhaust pipe 12 and is configured to recover heat from exhaust gas discharged from the gas turbine 8 to generate steam. The steam generated in the boiler 2 is supplied to an appropriate load system through a steam supply pipe 13, and is used as a heat source for the load system. The compression type water cooler 3 is a known type that uses a compressor and a refrigerant, and is connected to a cooling tower 14 via a cooling water circulation pipe 15. Note that this circulation pipe 15 is provided with a cooling water circulation pump 15a. In this embodiment, the input shaft 3a of the water cooler 3 is connected to a suitable transmission shaft 9a of the reduction gear mechanism 9 via a clutch 16, and the water cooler 3 is connected to a gas turbine in the gas turbine generator 1. It is devised so that it is driven by driving force. The air cooler 4 is provided with the intake pipe 5 and connected to the water cooler 3 via a cold water circulation pipe 18, and converts the air in the intake pipe 5 into cold water led from the water cooler 3. It is configured to cool by exchanging heat with. Note that the cold water is circulated between the water cooler 3 and the cooler 4 by the circulation pump 18a. By the way, the system of the present invention in the above embodiment and the conventional system mentioned at the beginning were operated under the conditions shown in Table 1 when the outside air temperature was 30°C (3 MW).
A comparative experiment was conducted to compare the performance of a power generation device of the same class (using a power generation device of the same class), and the results shown in Table 2 were obtained. Regarding the system of the present invention, experiments were conducted separately for cases in which the intake air temperature was cooled to 5°C and cases in which it was cooled to 12°C. From this experimental result, the system of the present invention, which cools the intake air temperature, generates more power than the conventional system (approximately 20 to 26
% increase), power generation efficiency (approximately 2% increase), and steam generation amount by waste heat recovery (approximately 2-3% increase). . On the other hand, cooling the intake air temperature requires a small amount of energy (in the case of cooling to 5 degrees Celsius, the water cooler driving power is approximately 110kw, the cooling water flow rate is approximately 71000kg/h, and the pump driving power is approximately 3.2kw. In the case of cooling to 12°C, the water cooler requires only about 75 kW of driving power, the cooling water flow rate of about 49,000 kg/h, and the pump driving power of about 2.2 KWh.

【table】

[Table] In addition, when determining the relationship between the generator end output and the outside temperature in the above-mentioned system of the present invention, the dashed line in Figure 3 shows the system that can be cooled to 5°C (dotted and dashed line), and the system that can be cooled to 12°C as the dashed line. is shown by a two-dot chain line), and it is understood that the output is hardly affected by the outside temperature. In addition, in the above embodiment, the exhaust heat recovery boiler 2
It goes without saying that a system equipped with a superheater or an energy saver may be used, and either a natural circulation type or a forced circulation type may be used. (Effects of the Invention) As can be easily understood from the above explanation, the gas turbine power generation system of the present invention does not reduce the amount of power generated even when the outside temperature is high, such as in the summer, and can be used regardless of changes in the outside temperature. It is possible to always demonstrate the maximum capacity, and it is possible to effectively increase or improve the amount of electric power generation, power generation efficiency, and amount of steam generation compared to conventional systems. Therefore, the gas turbine power generation system of the present invention can sufficiently cover the electricity and steam used in the factory throughout the year.

[Brief explanation of the drawing]

FIG. 1 is a system diagram showing an embodiment of the gas turbine power generation system according to the present invention, FIG. 2 is a system diagram showing a conventional gas turbine power generation system, and FIG.
The figure is a characteristic curve diagram showing the relationship between generator end output and outside air temperature when a 3 MW class gas turbine power generator is used. 1...Gas turbine power generation device, 2...Exhaust heat recovery boiler, 3...Compression water cooler, 4...Air cooler, 5...Intake pipe line, 6...Air compressor, 7...
Combustor, 8...Gas turbine, 8a...Gas turbine shaft, 9...Reduction gear mechanism, 9a...Transmission shaft,
10... Generator, 12... Exhaust gas discharge pipe, 13
...Steam supply pipe, 16...Clutch, 17...
Prime mover, 18...Cold water circulation pipe.

Claims (1)

[Claims] 1. In a gas turbine power generation system that combines a gas turbine power generation device and an exhaust heat recovery boiler, an air cooler is interposed in the intake pipe of the gas turbine power generation device, and a reduction gear mechanism is installed on the gas turbine shaft of the gas turbine. A gas turbine power generation system characterized by having a configuration in which a compression type water cooler is connected to the air cooler via the compression type water cooler, and chilled water is circulated from the compression type water cooler to the air cooler to cool air supplied to the turbine power generator.