JPS58176421A - Power generation by gas turbine engine - Google Patents

Abstract

PURPOSE:To enable the shifting between a no load operation and a loaded operation of the titled engine to be made only by the switching operation of a valve by a method wherein the compressor is evacuated or the air in the compressor is substituted with helium when air vaporized from liquid phase air is supplied so that the requiried driving power is applied on a generator to thereby increase the power generation output of the generator. CONSTITUTION:The liquid phase air 1 is stored in a storage vessel 3 from a pipe 2 and is introduced into the air turbine 13 through a liquid phase air vaporizer 6 and an air heater 9 via a pipe 2 and a pump 5 when the electric power demand reaches its peak so that the vaporized air expands adiabatically. Then the air sucked into the compressor 21 of the gas turbine 20 is introuced into a burner 22 after being compressed to about 12atm. and the resulatant combustion gas is introduced into the gas turbine 25 to generate a driving power so that the generator 24 is driven to generate electric power through a shaft 36 and at the same time, the compressor 21 is driven through a shaft 37. Further, after closing an inlet valve 27 of the compressor 21 to the full, the air in the compressor 21 and an air circulation passage is substituted with helium gas by opening a valve 50 provided in a pipe 49 leading to a helium gas vessel 51 whereby the compressor is operated in substantially a no-load operation condition.

Description

Detailed Description of the Invention The present invention produces and stores liquid air in advance, and pressurizes and vaporizes the liquid air during peak demand for electricity.The resulting pressurized air is then pressurized for combustion by a compressor. A method that facilitates no-load operation of the compressor and mutual switching in a gas turbine power generation method that increases power generation output by supplying fuel to a combustor instead of air to burn it and drive a gas turbine. be.

We have been manufacturing and storing liquid air for a long time! ! The compressed air obtained by boosting the pressure of this liquid air with a pump and vaporizing it during peak electricity demand hours is switched to supply the compressed air for combustion by the compressor, thereby driving the compressor during normal operation. A gas turbine power generation method has been proposed in which power generation efficiency is almost doubled by eliminating the need for the generated power of a gas turbine and using it for power generation (for example, Japanese Patent Laid-Open No. 52-34148).

That is, since gas turbine power generation has a configuration in which a compressor and a turbine are combined, the power generated by the turbine minus the power required for the compressor to compress air is extracted as the power generation output.

Generally, the power required for a compressor is approximately 60% of the power generated by a turbine.
For example, in a gas turbine with an output capacity of 10,000 kW, the power generated by the turbine is approximately 175,000 kW, and the power consumed by the compressor is 105,000 kW. Therefore, if compressed air is supplied from the outside, the ideal turbine output will be 17.5
It will now be possible to extract all 10,000 kW, making it possible to increase output by 105,000 kW without installing an additional gas turbine unit.

On the other hand, in order to increase the output by 105,000 kW using the conventional method, it is necessary to increase the capacity by installing, for example, a 70,000 kW gas turbine unit and a 35,000 kW steam turbine for recovering its exhaust heat. In order to supply compressed air from the outside, for example, liquid air is produced in advance using the cold energy of liquefied natural gas (LNG) released into seawater. As a method for manufacturing based on electric power consumption, methods such as Japanese Patent Laid-Open No. 140880/1983 have been proposed.

The liquid air produced by these methods is stored in a storage tank, and the pressure of the liquefied air is raised by a pump during peak electricity demand, and then it is vaporized and heated, and the resulting pressurized air is used to generate pressurized air using a compressor. Instead, it is fed to a gas turbine. However, when performing this gas turbine power generation method using externally pressurized air, it is difficult to smoothly switch between the supply of combustion air by the compressor and the vaporized liquid air without stopping the operation of the gas turbine. There was an inconvenience. That is, conventionally, a shaft coupling device was provided between the compressor and the gas turbine.
When vaporized liquid air is supplied to a gas turbine, the operation of the compressor is stopped by disconnecting the shaft connector. Therefore, when switching the supply source of compressed air to the gas turbine, there are inconveniences such as having to temporarily stop the operation of the gas turbine in order to operate the shaft coupler.

In view of the drawbacks of this conventional method, the present invention increases the power generation output by loading the required power to the generator by replacing the inside of the compressor with vacuum or helium and operating with no load when supplying vaporized liquid air. Thus, the transition to no-load operation and vice versa to load operation can be smoothly performed only by a valve switching operation. The present invention will be explained in detail below. FIG. 1 is a system diagram of an embodiment of the present invention. Liquid air 1 produced by the method described above is introduced into a storage tank 3 through a pipe 2 and stored therein, but during peak power demand, it is drawn out from a pipe 4 at a rate of 950T/11 and pumped to a pressure of about 200 atm by a liquid pump 5. The pressure is increased, the air enters the submerged vaporizer 6, is introduced through pipe 7, and is vaporized and heated by exchanging heat with the air discharged from pipe 8. It then enters air warmer 9, enters pipe 10, and enters pipe 11. After exchanging heat with the discharged seawater or heated waste water and warming it to room temperature (20C), it is drawn out from the pipe 12, introduced into the air turbine 13, and expanded adiabatically. The power generated by the air turbine 13 is recovered and used for other purposes. The air, which has been expanded to about 12 atmospheres by the air turbine 13 and cooled, enters the air warmer 9 again through a pipe 14, where it is heated by exchanging heat with the seawater or heated waste water, and then sent through a pipe 15 to a gas turbine unit 20, which will be described later. sent to.

The gas turbine unit 20 normally consists of an air compressor 21, a combustor 22, a gas turbine 23, an exhaust heat recovery boiler 25, and the air sucked into the air compressor 21 through a pipe 26, a valve 27, and a pipe 28. is compressed to approximately 12 atmospheres and is passed through pipes 29 and 30, valve 31, pipe 32.33i, and combustor 22.
The combustion product gas enters the gas turbine 23 through the pipe 35, where it generates power. The generated power drives the generator 24 through the shaft 36ft to generate electricity, and at the same time drives the air compressor 21 through the shaft 37.

However, in order to switch the pressurized air from the air compressor 21 in the gas turbine unit 20 to the pressurized air supplied via the pipe 15, first the valve 40 is opened and the air is supplied from the pipe 15 to the combustor 22 through the pipe 41.33. Pressurized air is sent in, and at this time, the valve 42 is controlled so that the pressure in the pipe 33 becomes constant, and the square 31 provided in the pressurized air delivery pipe 30.32 from the compressor 21 is operated in the closing direction. . When the amount of air in the pipe 41J reaches the rated value, the valve 31 is fully closed, but during that time the compressor 21
The discharge pressure is controlled by a discharge valve 43. After the air introduced into the combustor 22 has passed through the pipes 14 and 41 in this manner and has been switched to the next nine, the air compressor 21 is brought into a no-load state. That is, when the air compressor delivery valve 31 is fully closed, the valve 43 is open, but this opening degree is adjusted to reduce the discharge pressure of the air compressor 21 to the lowest possible liquid bottom pressure, and then By turning the compressor valve 27 in the closing direction, the pressure on the suction side of the compressor is reduced, and the release valve 43 is further adjusted so that the ratio of the suction pressure to the discharge pressure is within a safe range that does not cause a surging phenomenon. When the discharge pressure of the compressor 21 reaches atmospheric pressure, while maintaining that state, the nine valves 44 installed in the bypass line between the suction side and the discharge side are opened, and the discharge valve 4 to the atmosphere is opened.
3 in the closing direction, and finally the discharge valve 43 is fully closed. The air discharged from the compressor 21 is thus transferred to the pipe 29. Cooler 45. Valve 44. After circulating through the path of the pipe 28, the compressor artificial valve 27 is fully closed to make the above-mentioned differential flow path a closed system. Thereafter, the valve 47 provided in the pipe 46 leading to the evacuation device 48 is operated in the opening direction, and the pressure inside the closed system is reduced by the evacuation device 48. This evacuation operation progresses until the degree of vacuum within the closed system reaches a state in which the air compressor 21 is operating under almost no load. In addition to obtaining a no-load operating state by creating a vacuum inside the compressor 21 as described above, the same effect can be obtained by replacing the inside of the compressor 21 with helium gas, that is, the compressor artificial valve 2
7 is fully closed, the pipe 49 leading to the helium gas container 51
A state close to no-load operation can be obtained by opening the valve 50 provided in the compressor 21 and replacing the air in the compressor 21 and the differential path with helium gas.

By using the compressed air separately produced in this way in place of the pressurized air by the compressor 21 in the gas turbine unit 20, and by causing the compressor 21 to operate under no load, , it is possible to meet short-term peak power demand, but to do so, the generator 24 needs to have a capacity of 175,000 kW, for example, compared to the conventional capacity of 70,000 kW. Or 70,000k as shown in Figure 2
In addition to the W generator 24, there is also a 105,000 kW auxiliary generator 24.
' is coupled via a shaft 38, but this additional generator 24'
The connection position is not limited to the shaft end side, but is connected at an optimal position on one axis depending on the type of gas turbine.

As described above, the present invention provides an air path for the in-unit compressor of a gas turbine power generation system in which pressurized air is supplied from outside the gas turbine unit and introduced into the combustor instead of the pressurized air by the in-unit compressor. The compressor is made into a closed system, and the system is vacuumed or replaced with helium to enable no-load operation of the compressor, thereby almost doubling the power generation output. By making it possible to smoothly shift to reverse load operation only by operating the valve, the above switching operation can be performed at any time during operation, making it possible to easily cope with peak demand for electricity. .

[Brief explanation of drawings]

FIG. 1 is a system diagram showing one embodiment of the method of the present invention, and FIG. 2 is a diagram showing the main parts when an additional generator is installed. 3 is a storage tank, 5 is a liquid pump, 6 is a submerged vaporizer, 9 is an air heater, 13 is an air turbine, 20 is a gas turbine unit, 21 is an air compressor, 22 is a combustor, 23 is a gas turbine, 24 .24' is a generator, and 25 is an exhaust heat recovery boiler. Patent applicant Denki Kido, patent attorney representing Nippon Sanso Co., Ltd.
-Otoma Banbe Shigenori Toshio Tsuruwaka

Claims (1)

[Claims] ■Produced and stored in advance in a gas turbine power generation method in which fuel and pressurized air obtained by a compressor are supplied to a combustor for combustion, and the combustion gas is introduced into a gas turbine to obtain power and drive a generator. The pressurized air obtained by pressurizing and deaerating the liquid air with a pump is supplied to the combustor in place of the pressurized air by the compressor in response to an increase in power demand, and the air path of the compressor is closed. system, the compressor is operated under no load by vacuuming the closed system or replacing it with helium gas, and the driving power is diverted to increase the load on the generator or to drive the auxiliary generator. A gas turbine power generation method characterized by the following.