JPS6312834A - Underwater tank - Google Patents

Abstract

PURPOSE:To enable easy and safe installation of an underwater tank, by a method wherein, in a pressure accumulating air tank for air for pressurization combustion used for a gas turbine, pressurized air from an air compressing system is guided to a flexible tank installed in sea water through a pipe body. CONSTITUTION:A gas turbine generator feeds compressed air from an air compressing system 1 to a combustor, a turbine is driven by means of high pressure high temperature combustion gas generated in the combustor, and a power is generated by means of a generator. In this case, a flexible tank 7, installed in sea water, is connected to the air compressing system 1 through a pipe body 8. In which case, a depth H in water of a connection end 6 is set so that a sea water pressure at the connecting end 6 of the flexible tank 7 is adjusted to a pressure matching that of air 10 for combustion. Through utilization of a surplus power at night, the air compressing system 1 is driven, compressed air produced by the air compressing system is stored in the flexible tank 7, and during power generation in the daytime, the stored air is utilized as air for combustion.

Description

DETAILED DESCRIPTION OF THE INVENTION OBJECTS OF THE INVENTION (Field of Application of the Invention) The present invention relates to an accumulator for pressurized combustion air used in submersible tanks, such as gas turbines.

(Prior art and its problems) When operating power plants that make up an electric power system, nuclear power plants, where starting and stopping are generally undesirable, and pulverized coal-fired power plants, where starting and stopping are not easy, are used for base operation. When power demand increases during the day, power shortage officials will
Oil-fired power plants, LNG, and LPG that can be started and stopped quickly and easily
Thermal power plants as well as gas turbine power plants that use LNG gas as fuel are operated to meet the demand for electricity. Therefore, many power plants other than those for base operation are operated or shut down at night and other times.

A power plant that uses pressurized air to burn fuel,
For example, in a gas turbine power plant having a schematic configuration as shown in Fig. 1, air pressurized to about 10 atmospheres by an air compressor (1) is used as combustion air and is used in a combustor together with fuel gas (for example, LNG). In addition to (2), a working gas is created, which drives a gas turbine (3) to generate a generator (
4), the surplus power generated during the night and other times when the generator is stopped is used to drive the generator (4) as an electric motor to operate the air compressor (1), thereby generating electricity. It has been proposed to store the pressurized air in a storage device (5) excavated underground and use this stored air for combustion during power generation operation.

According to this method, the power of the air compressor, which requires the same or more power than the generated power, can be covered by inexpensive surplus electricity, which can greatly reduce fuel costs.For example, the surplus power can be used to generate nuclear power. If you use that, the fuel cost for power generation is currently 3 yen/KWh, and if LNG is used as the fuel for gas turbine power generation, it will be 10 yen/KWh, so 1O-3 = 7 yen. The power generation fuel cost per I KWh can be reduced. Additionally, compared to the conventional method, which generates combustion air by driving an air compressor at the same time as the gas turbine is operating, this method requires more power generation equipment by the amount of power required for the air compressor. For example, if the power generation power is 100,000 KW, the power required for the air compressor is 1
Since it will be more than 100,000 kW, it would be possible to obtain the same excellent effect as if the power generation equipment was increased by 100,000 kW.

In addition to the above, not only is the load multiplied by 1,000 machines, but
When used as a bank amplifier power plant in the event of a grid failure,
By opening the valve of the storage device, combustion air with the required pressure can be obtained immediately, so the startup speed is fast and about 90% of the load can be taken in a short time of about 10 minutes. Therefore, it has the effect of increasing the stability of the system.

However, in the conventional storage device, the air pressure changes depending on the use of the stored air, as shown in FIG. For this reason, the combustion state of the fuel gas changes and the operating state of the gas turbine changes, so there is a drawback that the operating efficiency, etc., cannot be avoided. In addition, it is desirable that a storage device dug underground be constructed economically so that the stored air does not escape from the wall, and for this purpose, it is necessary to be able to excavate into a stratum that is both dense and easy to excavate. Highly desired. However, in Japan, it is difficult to find suitable geological strata, and it can be said that there is no suitable location in the bay area, especially for the location of a power plant.

The present invention provides a constant pressure accumulating air device that can be easily applied to coastal power plants, and eliminates the drawbacks of conventional devices. Next, the details will be explained using the drawings.

[Structure of the invention]

(Means for Solving the Problems) FIG. 2 is a diagram showing an embodiment of the present invention, and the features of the present invention are as follows. That is, one end is connected to the air compression system (1
) and a flexible tank (7) (
A pressurized combustion air storage pipe (8) (for example, an iron pipe) is connected to a storage pipe (8) (for example, made of stainless steel plate or Teflon).

A vinyl pipe) is installed in the sea along the seabed (9), and is flexible so that the seawater pressure at the flexible tank connection end (6) can counteract that of the stored combustion air 0I11. The flexible tank connection end (6) is characterized by selecting a water depth l(), and the flexible tank (7)
The size, number, and wall thickness of the combustion air are determined by the amount of combustion air stored, pressure,
Selection is made based on water depth, etc. Note that 0υ is a weight for preventing the tube body (8) etc. from floating due to the pressurized combustion air, and is made of, for example, rock chips.

(Function and Effect) In the above, the pressure of the pressurized combustion air α0) is set to 10, for example.
If the pipe body (8) is installed at a constant water depth of 200 m, the seawater pressure acting on the flexible tank (7) of the pipe body (8) will be IO pressure, and the amount of combustion air will be The flexible tank (7) changes size as the use changes.

For this reason, the pressure does not change due to the use of combustion air, unlike the conventional storage device excavated and formed underground as shown in Figure 1, and is always maintained at a constant pressure, which does not adversely affect the operation of the turbine. .

In addition to this, the present invention is an underwater type, and as long as the required water depth is obtained, it can be made by simply laying a pipe body, and unlike underground excavation type, it can be easily used for excavation and decommissioning. It can be made relatively easily without any difficulty. Therefore, it is easy to apply to gas turbine power generation plants, which are mostly constructed on the bay or coast.

(Modified Example) The case where a flexible tank is used has been described above, but as shown in Fig. 3, a sunken ship a';! is disposed of at the underwater end (6) of the pipe body (8). Place the flexible tank (7) in it.
It can also be protected from external forces by providing a

Moreover, if the underwater end (6) is closed, it can be made into a transformer type. However, in this case, a diaphragm is required to prevent the influence of seawater on the turbine. Further, in the above description, a weight aυ was used as shown in FIG. 2 to prevent floating due to the stored air, but instead of this, a lock fill material may be filled into the pipe body (8).

This method is easy to implement as it is sufficient to drop the rockfill material from above ground, but if the rockfill material enters the combustor it will have an adverse effect on the turbine, so an appropriate diaphragm is required. In addition, although the above examples have been applied to gas turbines, for example, it can be applied to so-called combined cycle power generation in which the exhaust heat of the gas turbine drives a steam turbine to increase power generation efficiency, as well as equipment that requires storage of pressurized air, etc. It can be used as an oil storage tank for pond water storage, etc.

[Brief explanation of the drawing]

FIG. 1 is a system diagram showing an example of gas turbine power generation, FIG. 2 is a detailed explanatory diagram of the present invention, and FIG. 3 is a partial diagram of a modification of the present invention. (1)...Air compressor, (2)...Combustor, (3)
...gas turbine, (4)...generator, (5)...
・Storage device, (6)...Flexible tank connection end, (7)
... Flexible tank, (8) ... Pipe body, (9) ...
Seabed, Ql...combustion air, aυ...weight, αno...
...Shipwreck.

Claims (1)

[Claims] A pipe body with a filling port for stored pressurized air at one end and a flexible tank connected to the opening at the other end is installed at a depth where water pressure that can oppose the pressure of stored pressurized air can be obtained. A submersible tank featuring