JP3354750B2 - LNG vaporizer for fuel of natural gas-fired gas turbine combined cycle power plant - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to LNG (liquefied natural gas) for fuel of a natural gas-fired gas turbine combined cycle power plant.
More specifically, the amount of L required by the power plant is determined by utilizing the heat obtained by cooling the intake of the gas turbine of the power plant and the heat obtained by cooling the equipment of the power plant.
The present invention relates to a device for vaporizing NG and using the cold heat of the LNG to cool the intake air of the gas turbine to improve the output of the gas turbine.

[0002]

2. Description of the Related Art In recent years, a gas turbine combined cycle power plant using a gas turbine and a steam turbine has become the mainstream of a power plant using LNG as a fuel in order to effectively use energy.

[0003] However, the gas turbine combined cycle power generation equipment has a characteristic that, since the suction air flow rate of the gas turbine is a constant volume flow rate, the mass flow rate of the suctioned air decreases as the atmospheric temperature increases, and the output of the gas turbine decreases. There is a problem that power generation capacity is reduced in summer when power consumption is high.

In order to solve this problem, it is conceivable to cool the intake of the gas turbine by using the cold heat of the LNG and vaporize the LNG by using the heat obtained by cooling the intake. Unexamined Japanese Patent Publication No.
Means disclosed in Japanese Patent Application Publication No. 9-29904 has been proposed.

[0005] The essence of this proposal is, as shown in FIG.
G vaporized gas (3) and gas turbine intake cooling system (8)
And a circulating system for the first heat medium between the LNG vaporizer (3) and the regenerator (4), and between the regenerator (4) and the intake air cooling device (8). A circulating system for the second heat medium is provided to vaporize LNG and cool the heat storage agent (4a) in the heat accumulator in the circulating system for the first heat medium. Means for cooling.

This conventional means relies on only the heat obtained by cooling the intake of a gas turbine as a heat source for vaporizing LNG, and the amount of vaporized natural gas (NG) and the temperature of NG only depend on atmospheric conditions. In addition, when it is not necessary to cool the intake of the gas turbine in winter, for example, since the LNG vaporization heat source is eliminated, a new LNG using seawater as a heat source is used.
It has the disadvantage of requiring a vaporizer.

As is well known, the LNG vaporizer using seawater as a heat source has the following disadvantages.

(1) Since a large amount of seawater is required as a heat source for vaporizing LNG, a large-capacity seawater supply facility such as a seawater pump and a water intake facility is required, and the configuration of the LNG vaporization facility becomes complicated.

(2) Problems such as adhesion of marine organisms and corrosion of materials are likely to occur in the water-contacting portion of the seawater supply equipment.
This may make the maintenance work of the NG vaporization facility complicated and prolonged.

(3) Seawater used as a heat source for vaporizing LNG is discharged into the ocean, but its low temperature has some effect on marine ecosystems, and one constraint on the location of LNG vaporization facilities. Becomes

As a conventional apparatus for vaporizing and heating LNG using seawater or hot water as a heat source fluid, an apparatus disclosed in Japanese Patent Publication No. 61-24634 shown in FIG. 4 has been proposed.

As shown in FIG. 4, the gist of this proposal is supplied from a conduit 4 to a tube group in the heat exchanger 1 in an intermediate heat medium type indirect heat exchanger 1 having a built-in intermediate heat medium 1a. , The intermediate heat medium 1 by the heat source fluid flowing out of the conduit 5.
a is heated and evaporated, and the evaporated intermediate heat medium vapor,
The LNG supplied from the conduit 6 to the tube group 7 accommodated in the heat exchanger 1 is heated. The vapor of the intermediate heat medium is condensed and liquefied by heat exchange with LNG, falls into the lower liquid phase, and repeats evaporation again. LNG heated by heat exchanger 1
Is supplied to the shell-and-tube heat exchanger 2 through the conduit 8, and further heated by the heat source fluid supplied from the conduit 3 in the heat exchanger 2, and after being heated to a temperature suitable for use, is vaporized. This is a device of a system that is discharged from the conduit 9 as NG.

The drawbacks of this conventional system are the following two.

(1) In the multi-tubular heat exchanger 2, a method is employed in which LNG and a heat source fluid exchange heat directly without passing through an intermediate heat medium, and flammable LNG leaks into the heat source fluid line. Great potential. The reason is that this kind of LNG
The operating pressure of LNG in the vaporizer is usually 20-50 kg
/ Cm ² G, while the operating pressure of the heat source fluid is 10
kg / cm ² G or less, and even if a small defect such as a pinhole occurs in the heat exchanger 2, a large amount of LNG leaks into the heat source fluid line. In particular, when hot water from a power plant is used as a heat source fluid, if LNG leaks into this hot water line, flammable gas is diffused into the power plant, which poses a problem in the safety of the power plant.

(2) The replacement heat exchange between LNG and a heat source fluid that freezes at a temperature near 0 ° C. always involves the possibility of freezing the heat source fluid in the heat exchanger 2. If freezing occurs in the heat exchanger 2, the melting of the ice takes a long time and the vaporizing operation of LNG must be stopped during the melting operation. In addition, if ice is generated without reaching freezing, erosion occurs due to the separated ice chips, and the heat exchanger 2 is damaged, and LNG is generated.
Increases the likelihood of leakage into the heat source fluid line. In this conventional method, the heat exchanger 1 is heated so that the LNG is heated to a temperature at which ice is not generated in the heat exchanger 2.
Even if the above design is made, there is still a possibility of icing when the load of the LNG changes or when the flow rate of the heat source fluid changes. In particular, in a multi-tube heat exchanger, drifting is likely to occur in the fluid flowing in the tube group, and ice is easily generated in a tube in which the flow velocity of the fluid is low.

[0016]

SUMMARY OF THE INVENTION An object of the present invention is to provide an LN for fuel of a natural gas-fired gas turbine combined cycle power plant.
G can be continuously vaporized at least as long as the power station requires, and the cooling power of the LNG is used to cool the gas turbine intake air, thereby preventing the power generation capacity of the power plant from being reduced in summer and the like, and also ensuring safety. And to provide an LNG vaporizer excellent in economy. To achieve this goal, the following issues need to be solved.

In order to ensure the safety of the power plant, measures must be taken to prevent flammable gas from leaking out of the system and measures must be taken to easily detect even a small leak.

[0018] The intake of the gas turbine can be cooled by utilizing the cold heat of the LNG, and the heat obtained by cooling the intake of the gas turbine can be used as a vaporization heat source of the LNG.

Under all operating conditions of the power generation equipment, an inexpensive heat source that can supply the heat required to completely vaporize the LNG required by the power plant is prepared, and the heat source cools the intake of the gas turbine. Can be used at any time as an auxiliary heat source for the heat obtained.

The power used for operation of the LNG vaporizer and new heat sources such as steam can be reduced.

[0021] In summer, in which the intake cooling of the gas turbine is performed, a function of improving the intake cooling effect of the gas turbine in accordance with an increase in the atmospheric temperature is provided.

A factor that hinders normal operation of the LNG vaporization equipment, such as freezing of a heat source fluid, can be eliminated.

It is necessary to be able to vaporize the required amount of LNG by following the load fluctuation of the power generation equipment.

The temperature of NG is set to 0 for maintenance of the power generation equipment.
℃ or more.

[0025]

Means for Solving the Problems The inventors of the present invention have proposed, as means for solving the above problems, a fuel for a natural gas-fired gas turbine combined cycle power plant shown in the following [1] to [6]. The present invention proposes an LNG vaporizer for use.

[1] LN that heats LNG with heat medium vapor across a metal wall and cools and condenses the heat medium vapor
A G vaporizer; a heating medium evaporator for heating and evaporating the heating medium liquid cooled and condensed by the LNG vaporizer with water to generate the heating medium vapor and to cool the water; An intake cooler for cooling a gas turbine intake of a natural gas-fired gas turbine combined cycle power plant with the water cooled in the above; and an in-plant cooling water cooler for cooling water for cooling equipment of the power plant with seawater A pipe passing a water outlet of an in-house cooling water circulation pump that supplies water after cooling the power plant equipment to the in-house cooling water cooler to a water inlet of the in-house cooling water cooler; A pipe connecting a water outlet of the cooling water circulation pump to equipment of the power plant, bypassing the cooling water cooler in the plant; and a pipe connecting a water outlet of the suction cooler to a water inlet of the heat medium evaporator. A road and a cooling water circulation pump for said station A pipe connecting a water outlet of the heat medium evaporator to a water inlet of the heat medium evaporator; a pipe connecting a water outlet of the heat medium evaporator to a water inlet of the intake air cooler; and a water outlet of the heat medium evaporator. And a pipeline communicating at least one of the water outlet of the intake air cooler with at least one of the water inlet and the water outlet of the on-site cooling water cooler. LNG vaporizer for fuel of combined cycle power plant.

[2] The fuel for a natural gas-fired gas turbine combined cycle power plant according to [1], wherein the heat medium is 1,2,2,2-tetrafluoroethane [HFC-134a]. LNG vaporizer.

[3] The pipe passing through the water outlet of the in-house cooling water circulation pump to the water inlet of the in-house cooling water cooler and the water outlet of the in-house cooling water circulation pump bypassing the in-house cooling water cooler. An in-plant cooling water temperature control flow control valve provided in at least one of the pipelines communicating with the equipment of the power plant, and a temperature detector for detecting the temperature of water for cooling the equipment of the power plant. The method according to the above [1] or [2], further comprising: a gauge, and means for adjusting an opening of the flow rate control valve for adjusting the temperature of the in-house cooling water based on a detection value of the temperature detector. LNG vaporizer for fuel of natural gas-fired gas turbine combined cycle power plant.

[4] A pipe connecting the water outlet of the intake air cooler to the water inlet of the heat medium evaporator and a pipe connecting the water outlet of the in-house cooling water circulation pump to the water inlet of the heat medium evaporator. A flow control valve for adjusting the temperature of the water supplied to the heat medium evaporator, a temperature detector for detecting the temperature of water supplied to the heat medium evaporator, and detection of the temperature detector. Means for adjusting the opening of the flow control valve for adjusting the temperature of the supply water for the heat medium evaporator based on the value of the heat medium evaporator. LNG for fuel of gas-fired gas turbine combined cycle power plant
Vaporizer.

[5] The first heat medium evaporator housed in the liquid phase portion in the first heat medium evaporator body having the heat medium vapor phase in the upper part and the heat medium liquid phase in the lower part. Installed at a position higher than the installation position of the first heat medium evaporator, the upper part is connected by a conduit communicating with the heat medium vapor in the first heat medium evaporator body, and the lower part is connected to the first heat medium evaporator. First LNG contained in a body connected by a conduit communicating with a heat medium liquid phase in a body of a heat medium evaporator
A vaporizer and a second LNG vaporizer; a third LNG vaporizer housed in a heat medium vapor phase portion at an upper portion of the body in which the heat medium is sealed;
A second heat medium evaporator accommodated in a lower heat medium liquid phase portion in the body in which the heat medium is sealed; and LNG of the first LNG vaporizer
A conduit having an outlet communicating with the LNG inlet of the second LNG vaporizer; and an LNG outlet of the second LNG vaporizer being connected to the third LNG vaporizer.
A pipeline communicating with an LNG inlet of the NG vaporizer; a pipeline communicating a water inlet of the second heat medium evaporator with a water outlet of the intake air cooler and a water outlet of the in-house cooling water circulation pump; A pipe connecting the water outlet of the heat medium evaporator to the water inlet of the first heat medium evaporator; and a pipe connecting the water outlet of the first heat medium evaporator to the water inlet of the intake air cooler. The LNG vaporizer for fuel of a natural gas-fired gas turbine combined cycle power plant according to the above [1], [2], [3] or [4], characterized in that it is provided.

[6] A pressure detection / controller for detecting a pressure in the first heat medium evaporator and outputting a control signal, and an output signal of the pressure detection / controller and a demand signal of a water supply amount. A water flow signal selector for inputting and outputting a smaller one of them as a water supply amount setting signal;
A water flow rate detector for detecting a flow rate of water supplied to the heat medium evaporator, and a detection signal of the water flow rate detector and an output signal of the water flow rate signal selector are input to output a water flow rate control signal. Water supply amount control means comprising a water flow controller, and a water supply amount control valve to the first heat medium evaporator controlled by an output signal of the water flow controller; and the first heat medium evaporation A pressure detection / controller that detects the pressure in the chamber and outputs a control signal, and an output signal of the pressure detection / controller and a demand signal of the LNG supply amount are input and the smaller one of them is output. An LNG flow rate signal selector for outputting as an LNG supply amount setting signal; an LNG flow rate detector for detecting a flow rate of LNG supplied to the first LNG vaporizer; a detection signal of the LNG flow rate detector and the LNG flow rate selection LNG flow by inputting the output signal of the vessel An LNG flow controller for outputting a control signal, an LNG flow control valve provided at an LNG inlet of the first LNG vaporizer and controlled by an output signal of the LNG flow controller, and an LNG supply amount control means. The LNG vaporizer for fuel of a natural gas-fired gas turbine combined cycle power plant according to the above [5], comprising:

[0032]

[Action]

1) In the above solution [1], the heat medium heated with water and evaporated through the metal wall separates the LNG through the metal wall.
Is heated and vaporized, so that LNG does not leak into the water circulation system. Even if a defect such as a pinhole occurs in the metal wall separating the heat medium and LNG, the LNG
Leaks into the heat medium, the leak can be easily detected with a normal process instrument.

Further, since the intake of the gas turbine is cooled by the water cooled by the LNG via the heat medium, a decrease in the output of the gas turbine can be prevented even when the atmospheric temperature is high. Since the water heated by the intake of the gas turbine is used for heating the heat medium, the heat obtained by cooling the intake of the gas turbine is indirectly used for heating and vaporizing LNG.

Further, not only the hot water after cooling the power station equipment can be used for heating the heat medium, but also the heat generated by the power station equipment can be used in a required amount. This means that the conventionally discarded heat source can be used as a heating / vaporization heat source for LNG in a required amount.

In addition, when the heat generated by the equipment of the power plant is small, water for cooling the equipment (in-plant cooling water)
LNG at the water inlet of the on-site cooling water cooler that cools
Since the water cooled by the above is supplied to enable heating by seawater, for example, when the heat generated by the power plant equipment is small, the heat held by the seawater is used for heating and vaporizing heat source of LNG. As a result, it is possible to secure the LNG heating / vaporization heat source required by the power plant under all operating conditions of the power generation equipment.

When the heat generated by the equipment at the power plant is large, the low-temperature water cooled by LNG can be supplied to the water outlet of the in-house cooling water cooler. Pump power for seawater supplied to the water cooler can be reduced.

2) In the solution [2], since non-flammable HFC-134a is used as the heat medium, even if the heat medium leaks into the water circulation system, there is no fear of explosion or fire. HFC-134a has no toxicity and has no ozone depletion potential of 0, so there is no problem in preserving the global environment.

3) In the above solution [3], the pipeline for supplying the cooling water in the plant after cooling the equipment in the power plant to the cooling water cooler in the plant, and the cooling water in the plant bypasses the cooler in the plant. At least one of the pipelines is provided with a flow control valve, and the opening of the flow control valve is adjusted based on the temperature of the cooling water for cooling the power plant equipment. The temperature of the cooling water in the plant can be arbitrarily adjusted according to the amount of heat generated.

This ensures that the heat source for heating and vaporizing LNG is ensured regardless of the amount of heat generated by the equipment of the power plant, and by setting the temperature of the cooling water inside the plant high, the heat medium evaporation The amount of cooling water to be supplied to the vessel can be reduced, and the power for transporting the cooling water can be reduced.

4) In the above solution [4], the pipe after supplying the water after cooling the intake of the gas turbine to the heat medium evaporator and the water after cooling the equipment of the power plant are used as the heat medium evaporator. A flow control valve is provided in at least one of the pipelines for supplying gas to the heat medium evaporator, and the opening of the flow control valve is adjusted based on the temperature of the heat source water supplied to the heat medium evaporator. The heat obtained by cooling the power plant equipment can be used as necessary as an auxiliary heat source of the heat obtained by cooling, and the temperature of the heat source water supplied to the heat medium evaporator can be maintained at a predetermined value. it can.

5) In the above solution [5], first and second heat medium evaporators are provided, and the heat source water, that is, the water after cooling the gas turbine intake air and the temperature after cooling the power plant equipment and the like. At least one of the high-temperature water is first introduced into the second heat medium evaporator and cooled, and then introduced into the first heat medium evaporator and cooled, and then cooled in the intake cooler and the power plant. It is supplied to at least one of the cooling water circulation systems. LNG is first introduced into the first LNG vaporizer,
Next, the LNG which is sequentially supplied to the second LNG vaporizer and the third LNG vaporizer, and finally supplied to the third LNG vaporizer
Is heated by the high-temperature heat medium vapor generated in the second heat medium evaporator, so that NG easily becomes 0 ° C. or more. On the other hand, the cooling water used for cooling the intake air of the gas turbine can be set to a low temperature within a range where the cooling water does not freeze in the first heat medium evaporator.

This means that the temperature of the intake cooling water of the gas turbine can be lowered while maintaining the vaporized NG temperature at 0 ° C. or higher, and the intake cooling effect of the gas turbine can be improved.

6) In the solution [6], the first
A signal for detecting the pressure of the heat medium in the heat medium evaporator and adjusting the amount of water to be supplied to the first heat medium evaporator so that the pressure of the heat medium is constant; The demand signal of the desired water supply amount is compared, and the water amount supplied to the first heat medium evaporator is adjusted by the smaller one of the signals. Also, the supply amount of LNG is determined by detecting the pressure of the heat medium in the first heat medium evaporator and adjusting the LNG so that the heat medium pressure becomes constant.
Is compared with the demand signal of the desired LNG supply amount, and the signal is adjusted by the smaller one of the signals.

With this means, if the control target value of the heat medium pressure in the first heat medium evaporator is set to a pressure equal to or higher than the saturated vapor pressure of the heat medium at a temperature of 0 ° C., Water will not freeze.

Further, the control target value of the heat medium pressure for controlling the supply amount of LNG is equal to or higher than the saturated vapor pressure of the heat medium at a temperature of 0 ° C., and the control of the heat medium pressure for controlling the water supply amount. Under the condition set to a value lower than the target value, in summer when the intake cooling effect of the gas turbine is desired to be maximized, the set value of the water supply amount (demand signal) is set to a flow rate allowed by the equipment, and the LNG supply amount is set. Operate with the maximum value set. Then, the cooling water at the cooled temperature is obtained by maximizing the performance of the equipment without freezing the water, and the intake cooling effect of the gas turbine can be maximized.

Also, in winter, when it is desired to reduce the power used for operating the LNG vaporizer, that is, the power of the heat source water supply pump to the heat medium evaporator, the above solution [3],
When the temperature of the heat source water supplied to the second heat medium evaporator is adjusted to a high temperature using [4] and the operation is performed with the supply amount of LNG set to a desired value, the flow rate of the heat source water is automatically adjusted. That L
The minimum flow rate required for NG vaporization is obtained, and the pump power can be reduced.

[0047]

1 and 2 are system diagrams showing one embodiment of the present invention. That is, X, Y, and Z shown at the left end of FIG. 1 communicate with X, Y, and Z shown at the right end of FIG. 2 to complete the present embodiment. It will be described as.

(1) is a first heat medium evaporator in which a heat transfer tube group (1a) is disposed in the body. This first heat medium evaporator (1)
The heat medium (A) accommodated in the body side of is heated and evaporated by the water flowing from the water supply port (23i) into the heat transfer tube group (1a) through the water supply pipe (23). The evaporated heat medium vapor is discharged from the heat medium vapor outlet (5θ). The water flowing in the heat transfer tube group (1a) and cooled by the latent heat of evaporation of the heat medium (A) outside the tubes is discharged from the water discharge port (22θ).

(2) shows a body in which a U-shaped tube group (3a) of the first LNG vaporizer (3) and a U-shaped pipe (4a) of the second LNG vaporizer (4) are arranged. The heat medium vapor evaporated in the first heat medium evaporator (1) is introduced from the heat medium evaporator supply port (5i) through the conduit (5) to the barrel side of (2). On the other hand, LNG passes through the LNG supply pipe (7),
First, it is introduced into the first LNG vaporizer (3) from the LNG supply port (7i), passes through the U-shaped tube group (3a), and is discharged from the LNG discharge port (8θ) to the LNG conduit (8), and further LN
G conduit (8) through the LNG supply port (8i) to the second L
It is introduced into the NG vaporizer (4) and discharged from the LNG outlet (9θ) through the U-shaped tube bank (4a) to the LNG conduit (9). The LNG is heated and vaporized by the heat medium vapor supplied from the heat medium vapor supply port (5i) while passing through the U-shaped tube banks (3a) and (4a).

On the other hand, the heat medium vapor is condensed and liquefied by heating and vaporizing the LNG, and the condensed and liquefied heat medium is discharged from the heat medium discharge port (6θ) and passed through a conduit (6) to supply the heat medium supply port. From (6i), it is circulated in the body of the first heat medium evaporator (1). That is, the first LNG vaporizer (3) and the second LNG vaporizer (3)
The body (2) containing the LNG vaporizer (4) is installed at a position higher than the installation position of the first heat medium evaporator (1), and the heat medium is connected to the first heat medium evaporator (1) and the first LNG. Self-circulation between the vaporizer (3) and the body (2) accommodating the second LNG vaporizer (4) is provided.

The first LNG vaporizer (3) and the second LNG vaporizer (4) are housed in separate bodies, and the first heat medium evaporator (1)
May be introduced separately, and LN
The number of constituent units of the G vaporizer can also be arbitrarily selected. However, the tube sheet of the first LNG vaporizer (3) into which the cryogenic LNG of -100 ° C or less is introduced is preferably small in terms of measures against thermal stress, and the heat transfer area of the first LNG vaporizer (3) is not increased. It is necessary to consider. Therefore, the first L
In the NG vaporizer (3), it is preferable to perform preheating of LNG, that is, heating of LNG to near the boiling point, and vaporize LNG requiring a large amount of heat in the second LNG vaporizer (4). In addition, from the viewpoint of reducing equipment costs, the first LNG
It is expedient to house the vaporizer (3) and the second LNG vaporizer (4) in one fuselage (2).

(10) shows a body provided with a tube group (12a) of the second heat medium evaporator (12) and a U-shaped tube group (11a) of the third LNG vaporizer (11). (10)
The heat medium (A) accommodated in the body side of the water flows through the water supply pipe (24) through the water supply port (24i) into the heat transfer tube group (12a), and flows through the water discharge port (23θ) into the water supply pipe ( It is heated by the water discharged to 23) and evaporated. The evaporated heat medium vapor condenses on the tube wall of the U-shaped tube group (11a) by heating the LNG flowing through the LNG supply port (9i) through the LNG supply port (9i) in the U-shaped tube group (11a). Liquefaction,
It falls on the liquid surface of the heat medium (A) by its own weight. On the other hand, LNG heated by the heat medium vapor becomes NG at 0 ° C. or higher and becomes NNG.
It is discharged from the G discharge port (13θ) to the NG conduit (13).

The second heat medium evaporator (12) and the third LNG vaporizer (11) are composed of the first heat medium evaporator (1) and the first LN
In the same manner as the body (2) containing the G vaporizer (3) and the second LNG vaporizer (4), they are housed in separate bodies, and both bodies are connected by a heat medium vapor conduit and a heat medium liquid conduit. However, it is preferable to house them in the same body (10) from the viewpoint of reducing equipment costs.

The heat medium (A) filled in the body (10) of the first heat medium evaporator (1) and the second heat medium evaporator is vaporized by the heat medium evaporator and liquefied by the LNG vaporizer. Such a substance needs to be a substance that undergoes a gas-liquid phase change under the operating conditions of a so-called vaporization facility and transfers heat accordingly. Further, a substance having a low freezing point, nonflammability, non-toxicity and no problem in preserving the global environment is preferable. As such a substance, for example, 1,2,2,2-tetrafluoroethane (HFC-1
Preferably, 34a) is used. That is, HFC-
The freezing point of 134a is as low as -101 ° C and extremely low temperature LNG
Is vaporized in the LNG vaporizer.
There is no concern that FC-134a will solidify and interfere with normal operation. The biggest concern that hinders the normal operation of the LNG vaporization equipment is the freezing of the heat source water in the heat medium evaporator. This problem is solved by using the means described below to reduce the heat medium temperature in the heat medium evaporator to zero.
The problem can be solved by maintaining the temperature at not less than ° C.

When HFC-134a is used as the heat medium, the heat source water exchanges heat with the nonflammable HFC-134a liquid, and the LNG exchanges heat with the nonflammable HFC-134a vapor. That is, all the points where the heat source water and the LNG directly exchange heat as in the conventional LNG vaporizer are excluded, and there is no possibility that the LNG leaks into the heat source water.

For example, even if LNG leaks into the heat medium vapor due to a defect in the vaporizer, LNG does not exist in a liquid state under the operating conditions of the heat medium, and LNG does not exist in the heat medium liquid on the heat medium evaporator side. LNG is not mixed. Further, LNG leaked into the heat medium vapor becomes non-condensable gas and hinders heat exchange between the heat medium vapor and the LNG in the vaporizer. For this reason, even in the case of a small amount of leakage, the pressure of the heat medium vapor system rises above the saturated vapor pressure of the heat medium.

Therefore, by monitoring the pressure and temperature of the heating medium vapor system using an appropriate process instrument (without a diagram), the LN
A small leak of G can be easily detected, and based on this detection, LN
LNG in heat source water by measures such as shutting off the supply of G
Leakage can be completely prevented. In addition, leakage of LNG to the atmosphere can be easily detected by gas detection means conventionally employed in this type of gas equipment. That is, according to the present embodiment, the above-mentioned problem can be solved, and the hot water of the power plant can be used as the heat source water.

(21) shows a gas turbine facility, which is composed of main facilities of an air compressor (21a), a combustor (21b), and a gas turbine (21c). NG for fuel is NG
The combustion air is introduced into the combustor (21b) through the conduit (13), and the combustion air is supplied from the intake duct (19) to the air compressor (21b).
a) is sucked and supplied to the combustor (21b), and the combustion gas is introduced into the gas turbine (21c). As is well known, since the air compressor (21a) of the gas turbine (21c) is of a constant displacement type, the mass of the sucked air decreases as the intake air temperature increases, resulting in the gas turbine (21c).
Lower the output.

Therefore, there is a disadvantage that the amount of power generation decreases in summer when the power consumption increases, and it is a problem here to try to eliminate this disadvantage. That is, LNG
To cool the intake of the gas turbine (21c) by utilizing the cold heat of the gas turbine, and an intake air cooler for cooling the intake of the gas turbine (21c) is provided in an intake duct (19) of the gas turbine (21c). (20) is the air inlet (19
i) and the air outlet (19θ).

The intake air cooler (20) and the second heat medium evaporator (12) and the first heat medium evaporator (1) are connected to a water conduit (24) through an intake cooling water circulation pump (25). , (2
3) and (22) are connected in this order to form a gas turbine intake cooling water circulation system.

That is, extremely low temperature LN of -100 ° C. or less
In order to set G to NG of 0 ° C. or more, the second heat medium evaporator (1
2) By cooling the intake air of the gas turbine (21c) with water cooled by the latent heat of evaporation of the heat medium evaporated in the first heat medium evaporator (1), and cooling the intake air of the gas turbine (21c). The heating medium is heated and evaporated by the heated water, and LNG is heated and vaporized by the evaporated heating medium vapor.

It is preferable to cool the intake air of the gas turbine (21c) as much as possible to enhance the intake air cooling effect. For this reason, in the intake air cooler (20), a finned heat transfer tube group (20a) for flowing water is provided with a water supply port (22i) and a water discharge port (24).
θ). Although various types of heat transfer tube groups can be selected as the heat transfer tube group of the intake air cooler, a finned tube group that has a small air flow pressure loss and a large heat transfer area per unit volume of the intake air cooler is preferable.

In order to improve the intake air cooling effect, it is necessary to lower the cooling water supplied to the intake air cooler (20), that is, the water temperature at the first heat medium evaporator outlet (22θ). However, there is a restriction that the temperature of the vaporized NG is maintained at 0 ° C. or higher and ice is not generated in the water pipe of the heat medium evaporator.

However, according to the present embodiment, the heat medium vapor heated and evaporated with warm water in the second heat medium evaporator (12), and NG is finally heated, so that the first heat medium evaporator outlet Even if the water temperature of (22θ) is lowered, the vaporization NG temperature can easily be increased to 0 ° C. or higher. Further, a place where ice may be generated in the water pipe is in the water pipe of the first heat medium evaporator (1). However, according to the present embodiment, this can be easily solved as described later.

When the atmospheric temperature is lowered, it is not possible to vaporize all the LNG required by the gas turbine combined brand with only the heat obtained by cooling the intake of the gas turbine. It also seeks to use the heat obtained by cooling the equipment of the power plant, that is, a heat source that has never been used before.

(31) indicates the equipment of the power plant, and (3)
4) shows an in-plant cooling water circulation pump for circulating water (in-plant cooling water) for cooling equipment (31) in the power plant, and (39) in-plant cooling for cooling the in-plant cooling water with seawater. Shows a water cooler. The usual means of cooling the power plant equipment (31) consists of connecting these equipment to conduits (33),
It is only the connection in (35) and (32) that forms the in-site cooling water circulation system.

That is, the in-plant cooling water heated by cooling the power plant equipment (31) is supplied to the conduit (33).
After being drawn into the cooling water circulation pump (34) through the pipe, the water is supplied from the water inlet (35i) to the body side of the cooling water cooler (39) through the conduit (35) and introduced from the conduit (40). After being cooled by seawater flowing out of the conduit (41) through the heat transfer tube group (39a), the water outlet (23)
θ) and is again used for cooling the power plant equipment (31) through the conduit (32).

The biggest disadvantage of this conventional means is that the temperature of the cooling water inside the plant cannot be adjusted to a predetermined value, and as a result, the heat obtained by cooling the equipment (31) of the power plant is used as a heat source for vaporizing LNG. It will be unavailable. However, this inconvenience can be easily solved by using the means of this embodiment.

In the present embodiment, the water outlet (35θ) of the in-plant cooling water circulation pump (34) and the in-plant cooling water cooler (3
9) In addition to the pipe (35) communicating with the water inlet (35i), the pipe for flowing the cooling water inside the plant bypassing the cooling water cooler (39) for the factory, that is, the pipe for the cooling water cooler (39) for the factory. A pipe (32) connecting the water outlet (32θ) with the equipment (31) of the power plant and a pipe (3) connecting the pipe (35).
6) is provided to adjust the amount of water supplied to the in-house cooling water cooler (39) so that the heat removal amount in the in-house cooling water cooler (39) can be adjusted.

In the present embodiment, in order to adjust the heat removal amount in the in-plant cooling water cooler (39), the in-plant cooling water circulation pump (3) is used.
4) Flow control that operates in opposite directions to a pipe line (35) for supplying water to the cooling water cooler (39) and a pipe (36) for flowing water by bypassing the cooling water cooler (39). Valves (37a) and (37b) are provided, and the temperature of the cooling water used for cooling the equipment (31) of the power plant is detected by the temperature detector / controller (37), and based on the detected value, To control the opening of the flow control valves (37a) and (37b). The water flowing through the flow control valve (37b) is cooled by the on-site cooling water cooler (39).
It is cooler than the water flowing through a).

Therefore, when the temperature detected by the temperature detector / controller (37) is lower than the control target temperature, the flow control valve (37a)
Is operated in the opening direction, and conversely, the opening of the flow control valve (37b) is operated in the closing direction to control the in-plant cooling water temperature to the control target value. The purpose of this control is to adjust the heat removal amount of the in-plant cooling water cooler (39) to control the temperature of the in-plant cooling water to a predetermined value.
Only one of 7a) and (37b) may be installed, and the installation position of the flow control valve may be arbitrarily selected as long as the amount of water supplied to the in-house cooling water cooler (39) can be adjusted. Can be.

As described above, by adopting the means capable of adjusting the temperature of the cooling water inside the plant to a predetermined value, the heat obtained by cooling the equipment (31) of the power plant can be used as a heat source for vaporizing LNG. . Specifically, a conduit communicating between a water outlet (24θ) of the intake air cooler (20) and a water inlet (24i) of the second heat medium evaporator (12) via an intake air cooling water circulation pump (25). A water outlet (35θ) of the in-site cooling water circulation pump (34) is provided by providing a conduit (38) for communicating the (24) with the in-site cooling water circulation system conduit (35).
Is connected to a water inlet (24i) of the second heat medium evaporator (12) through an intake air cooling water circulation pump (25) to cool the in-site cooling water after cooling the power plant equipment (31). So that it can be supplied to the evaporator.

In this way, the heat obtained by cooling the power plant equipment (31) can be indirectly used as the LNG vaporization heat source via the heat medium (A).

Further, conduits (26) and (28) for communicating the conduits (24) and (35) and conduits (26) and (29) for communicating the conduits (24) and (32) are provided. The water outlet (24θ) of the intake air cooler (20) communicates with the water inlet (35i) and the water outlet (32θ) of the on-site cooling water cooler (39). By doing so, the water after cooling the intake of the gas turbine (21c) is equal to the in-plant cooling water supplied to the intake cooling water circulation system by the same amount as the in-plant cooling water cooler (39). After being cooled by the cooling water cooler (39), it can be returned to the cooling water in the place.

In the present embodiment, the amount of cooling water supplied to the intake cooling water circulation system is adjusted by adjusting the water outlet (24θ) of the intake cooling device (20) via the intake cooling water circulation pump (25). A flow control valve (30a) and a flow control valve (30a) which operate in reverse to each other are provided on the water suction side of the intake cooling water circulation pump (25) of the pipe (24) communicating with the water inlet (24i) of the medium evaporator and the pipe (38). 30b), the temperature of the water supplied to the second heat medium evaporator (12) is detected by the temperature detection / controller (30), and the flow control valves (30a) and (30b) are detected based on the detected values. ) Is controlled. In this control, when the water flowing through the flow control valve (30a) is a low temperature fluid and the water flowing through the flow control valve (30b) is a high temperature fluid, and the temperature detected by the temperature detection / controller (30) is lower than the control target value. Operates in the direction to close the opening of the flow control valve (30a) and in the direction to open the opening of the flow control valve (30b), and controls the temperature of the water supplied to the heat medium evaporator to a predetermined value. You. The flow control valves (30a), (30b)
May be installed, and the installation position may be arbitrarily selected as long as the amount of water supplied to the second heat medium evaporator (10) can be adjusted.

In winter, when the atmospheric temperature is low and it is not necessary to cool the gas turbine intake, only the cooling water in the station is supplied to the heat medium evaporator, and the water at the outlet of the heat medium evaporator is supplied to the intake cooler (2).
0) without passing through, the water inlet (35i) of the in-house cooling water cooler (39) or the in-house cooling water cooler outlet (32θ)
Return into the current. That is, the water outlet (22θ) of the first heat medium evaporator (1) and the water inlet (22) of the intake air cooler (20).
i), and a pipe (27) communicating with the pipes (28) and (29). The water cooled by the heat medium evaporator is used to cool the in-plant cooling water cooler ( The water is returned to the water flowing out from the water inlet (35i) of 39) or the water outlet (32θ) of the on-site cooling water cooler (39).

The water inlet (35) of the in-plant cooling water cooler (39)
Returning the water cooled by the heat medium evaporator to i) is intended to heat the water cooled by the heat medium evaporator with seawater which is usually used for cooling the cooling water inside the plant. In a plant with a small heat treatment capacity of the cooling water system, L
This is an effective means for securing an NG vaporization heat source.

The seawater temperature around the place where the LNG-fired gas turbine combined cycle power plant is installed in Japan is 7 to 8 ° C. or higher even in winter, and water cooled to 1 to 4 ° C. by the heat medium evaporator is used. Can be heated. That is, the water cooled to 1 to 4 ° C. by the heat medium evaporator is supplied to the in-house cooling water cooler (3).
After being heated to near seawater temperature in 9), it is further heated by the heat generated by the equipment (31) in the power plant, and becomes heat source water for vaporizing LNG. Only the heat input from the seawater of the in-plant cooling water cooler and the heat generated by the equipment (31) of the power plant require the required LN.
If the vaporization heat source for G is insufficient, another auxiliary heat source for vaporizing LNG is required.

As the auxiliary heat source for vaporizing LNG, steam easily available from a power plant is appropriate, and a steam heater (not shown) industrially frequently used in the discharge line of the intake cooling water circulation pump (25). And means for adjusting the temperature of the heat source water supplied to the heat medium evaporator.

On the other hand, the processing heat of the cooling water system in the plant is large,
In a combined plant in which the required LNG vaporization heat source can be sufficiently secured, it is appropriate that the water cooled by the heat medium evaporator is returned to the water stream flowing out from the water outlet (32θ) of the on-site cooling water cooler (39). is there. This is intended to use the water cooled by the heat medium evaporator for cooling the equipment (31) of the power plant, thereby reducing the heat load of the on-site cooling water cooler (39). As a result, the load on the seawater pump for cooling the cooling water in the plant can be reduced.

Next, control means around the LNG vaporizer of this embodiment will be described.

The functions required for the control system around the LNG vaporizer are as follows.

Do not create ice in the water tube of the heat medium evaporator under any operating conditions.

Following the fluctuation of the load of the power generation equipment,
LNG load can be adjusted.

In summer when the atmospheric temperature is high, LN
If the G supply is set to the maximum flow rate allowed by the equipment,
The cooling water amount must be the maximum flow rate allowed by the facility, and the cooling water temperature must be the lowest temperature that can be achieved in terms of the performance of the facility, so that the intake cooling effect of the gas turbine can be maximized.

In winter when the intake cooling of the gas turbine is not required, if the supply amount of LNG is set to be approximately equal to the fuel consumption amount of the power plant, the flow rate of the heat source water supplied to the heat medium evaporator will evaporate the LNG. That the minimum flow required for the pump can be reduced and the pump power can be reduced.

The above functions can be easily achieved by using the control means of this embodiment.

First, water flow control means will be described.
(18a) indicates a flow rate detector of water supplied to the second heat medium evaporator (12) and the first heat medium evaporator (1), and (18)
Denotes a water flow controller, and (18b) denotes a water flow control valve. (16b) indicates a pressure detection / controller in the first heat medium evaporator (1), and (17) indicates a water flow signal selector. When the pressure in the first heating medium evaporator (1) falls below a set value, a signal in the direction of increasing the flow rate of water, that is, an output signal, becomes a large value. If it becomes above, the signal of the direction to reduce the flow rate of water,
That is, the operation is performed so that the output signal becomes small.

The water flow signal selector (17) receives the demand signal of the water supply amount, that is, the setting signal of the water supply amount and the signal from the pressure detection / controller (16b), and receives the smaller signal, that is, the water flow amount. It has a function of selecting a signal for decreasing the opening of the control valve (18b) and outputting the signal to the water flow controller (18). The water flow controller (18) receives the detection signal of the water flow detector (18a) and the output signal of the water flow signal selector (17) and inputs the water flow control valve (18b). It has a function to output a control signal to

Next, the LNG supply control means will be described.

(14a) is the LN supplied to the LNG vaporizer
G shows a flow detector, (14) shows an LNG flow controller, and (14b) shows an LNG flow control valve. Also,
(16a) shows a pressure detection / controller in the first heat medium evaporator (1), and (15) shows an LNG flow signal selector. When the pressure in the first heat medium evaporator (1) becomes equal to or lower than a set value, the pressure detection / controller (16a) generates a signal in the direction of decreasing the flow rate of LNG, which is opposite to the case of the flow rate control of water. If the output signal decreases and the pressure exceeds the set value, LN
It operates so that the signal in the direction of increasing the flow rate of G, that is, the output signal is increased.

The LNG flow signal selector (15)
Demand signal of supply amount and pressure detection / controller (16
The output signal of a) is received, and a smaller one of the two, that is, a signal for decreasing the opening degree of the LNG flow control valve (14b) is selected, and the signal is selected as the LNG flow controller (14). It has the function to output to. The LNG flow controller (14) receives the detection signal of the LNG flow detector (14a) and the output signal of the LNG flow signal selector (15) and sends a control signal to the LNG flow control valve (14b). Has the function to output

The pressure in the first heat medium evaporator (1) is almost equal to the saturated vapor pressure of the heat medium in the evaporator, and the set values of the pressure detection / controllers (16a) and (16b) are set to 0 ° C. If the pressure is equal to or higher than the saturated vapor pressure of the heat medium in the first heat medium evaporator (1), the temperature of the heat medium in the first heat medium evaporator (1) does not fall below 0 ° C. Never freezes and the first
Ice is not generated at all in the tube group (12a) of the second heat medium evaporator to which the hot water is supplied before the heat medium evaporator (1) is supplied.

The set value of the pressure detector / controller (16a) for adjusting the flow rate of LNG is set to the minimum allowable value when the supply amount of LNG is set to the maximum allowable flow rate of the equipment (for example, the heating medium at 0 ° C.). (Saturated vapor pressure), and the set value of the pressure detector / controller (16b) for adjusting the flow rate of water,
If the heat medium temperature is set to a pressure (for example, the saturated vapor pressure of the heat medium at 1 ° C.) at which the temperature of the heat medium does not become 0 ° C. or less even when the load of LNG fluctuates, ice can be generated in the water pipe of the heat medium evaporator. In addition, the operation that follows the load fluctuation of the LNG and maximizes the cooling effect of the intake air of the gas turbine and the operation that minimizes the pump power of the intake cooling water circulation pump (25) can be easily performed.

The reason will be described in more detail.

Now, the water supply amount demand signal, that is, the set value of the water supply amount, is set to the maximum flow rate allowed by the equipment,
The set value of the pressure detector / controller (16a) is set to the saturated vapor pressure of the heat medium at 0 ° C., the set value of the pressure detector / controller (16b) is set to the saturated vapor pressure of the heat medium at 1 ° C. Consider a state in which the temperature of the heat source water at the outlet of the cooling water circulation pump (25) is controlled to a predetermined temperature.

First, assuming that the demand signal of the supply amount of LNG is set to the maximum value for the purpose of maximizing the intake air cooling effect of the gas turbine, the pressure in the first heat medium evaporator (1) is determined by the pressure detection / controller. The temperature of the heat medium drops to near 0 ° C. as the set value of (16a) approaches. In this state, the output signal of the pressure detector / controller (16b) for adjusting the flow rate of water becomes larger than the demand signal of the water supply amount, and the output signal from the water flow rate signal selector (17) becomes the water supply amount. The amount becomes a demand signal, and the supply amount of water is controlled to the maximum flow rate (set value) allowed by the equipment.

On the other hand, the output signal of the pressure detector / controller (16a) for adjusting the LNG flow rate is smaller than the demand signal of the LNG supply amount, and the output signal from the LNG flow rate signal selector (15) is Pressure detection / controller (16
a), and the supply amount of LNG is controlled such that the pressure in the first heat medium evaporator (1) becomes the set value of the pressure detection / controller (16a).

Such a state depends on the amount of water supplied and LNG.
Is the maximum flow rate allowed by the equipment and the temperature of the heat medium in the first heat medium evaporator (1) is also the lowest temperature, so that the water cooled by this heat medium also has a low temperature. That is,
The cooling water supplied to the intake air cooler (20) has a maximum flow rate allowed by the equipment and is cooled by maximizing the performance of the equipment, so that the intake cooling effect is also maximized. Further, such a condition is a condition in which the flow rate of water in the water pipe (1a) of the first heat medium evaporator (1) is maximum and ice is not easily generated, and the load of LNG is also maximum and the LNG load is maximum. There is no load increase, and even if the temperature of the heat medium in the first heat medium evaporator (1) is 0 ° C., there is no concern that ice will be generated in the water pipe. Note that when such an operation is performed, the amount of vaporized NG may exceed the fuel consumption of the power plant. In this case, surplus NG is diverted to another fuel.

Next, for example, in winter when intake cooling is not required, L
The characteristics of the system when the supply amount of NG is reduced to about the fuel consumption amount of the power plant will be described.

Assuming that the demand signal of the LNG supply amount is set to a small value, the pressure in the first heat medium evaporator (1) becomes close to the set value of the pressure detection / controller (16b) and the heat medium temperature becomes The temperature rises to about 1 ° C, and the pressure detection and controller (16
The output signal of b) becomes smaller than the demand signal of the water supply amount, the output signal from the water flow rate signal selector (17) becomes the signal from the pressure detection / controller (16b), and the water supply amount is the first heat. The pressure in the medium evaporator (1) is controlled at a required minimum flow rate which becomes a set value of the pressure detection / controller (16b).

On the other hand, the output signal of the pressure detector / controller (16a) for adjusting the LNG flow rate is larger than the demand signal of the LNG supply amount, and the output signal from the LNG flow rate signal selector (15) is An LNG supply amount is a demand signal, and the LNG supply amount is controlled by the LNG supply amount demand signal.

That is, according to the present embodiment, the predetermined LN
This makes it possible to minimize the necessary amount of heat source water for vaporizing G, and it is possible to reduce the power required for the vaporizing operation of LNG. In particular, in winter when intake cooling is not required, if the heat source water temperature is set higher using the means [3], the power saving effect required for the LNG vaporization operation is further improved. Further, under conditions where the supply amount of LNG is equal to or less than the limit value of the installed capacity and the load of LNG may increase, the temperature of the heat medium in the first heat medium evaporator (1) is maintained at a high temperature, and the heat source water is discharged. The flow rate is operated in a state where there is a margin in the equipment, and even when the load of the LNG is increased, the LNG can be vaporized without generating ice in the water pipe of the first heat medium evaporator (1).

In this embodiment, the conduit (22) communicating from the water outlet (22θ) of the first heat medium evaporator (1) →
A conduit (28) connecting the conduit (24) → (26) communicating from the water outlet (24θ) of the (27) and intake air cooler (20) to the water inlet (35i) of the on-site cooling water cooler (39).
And the conduit (29) communicating with the water outlet (32θ) has been described.
(26), (28) and (29), if necessary, a flow control valve or a flow control valve is interposed as needed, and the flow control valves or the flow control valves are controlled or adjusted in association with each other. It is possible to control and adjust various flow distributions in accordance with the operation status of the power plant, and it is a matter of course that such applications are included in the scope of the technical idea of the present invention.

The present invention is not limited to the above-described embodiment, but falls within the scope of the present invention described in the appended claims.
It goes without saying that various changes may be made to the specific configuration.

[0106]

As is apparent from the above description, the following effects can be obtained according to the present invention.

(A) It is possible to cool the intake of the gas turbine by using the cold heat of the fuel LNG of the natural gas-fired gas turbine combined cycle power plant, and to prevent a decrease in the output of the power plant in summer. .

(A) As a heat source for vaporizing LNG for fuel in a power plant, not only a heat source obtained by cooling the intake of a gas turbine but also a high-quality heat source and a power plant obtained by cooling equipment of the power plant. The heat input from the seawater of the in-site cooling water cooler, which is indispensable, can be used as needed, so that the amount of LNG required by the power plant can be stably vaporized even in winter, and LNG can be used. The power and auxiliary heat source required for the gasification operation can be reduced.

(C) Heat transfer between the LNG vaporization equipment and the power generation equipment, that is, the closed loop system of the cooling water in the plant is used to perform the above (A) and (A), so that seawater is used as the LNG vaporization heat source. Installation of special equipment such as seawater intake / drainage equipment such as conventional LNG vaporization equipment to be used, maintenance of those equipment against infestation and fouling of marine life, outflow of cold and hot water to public sea areas, etc. Not only the accompanying problems can be avoided, but also the quality of the cooling water in the plant can be easily maintained because of the closed loop system.

(D) By exchanging heat between the heat source water and LNG through a nonflammable heat medium, the LNG vaporization equipment
Leakage of combustible gas to the outside of the system, especially to the power generation equipment, is prevented, and the safety of the power plant is ensured in implementing the above (A), (A), and (C).

(E) The LNG vaporization equipment of the present invention can generate the required amount of natural gas suitable for the fuel of the power plant at any time in accordance with the load fluctuation of the power plant, and hinders the normal operation of the equipment. Concerns about freezing of water in the facility have been resolved, and a highly reliable power generation fuel facility has been provided. That is, the present invention provides an LNG vaporizer for fuel of a natural gas-fired gas turbine combined cycle power plant that is excellent in performance, safety, and economy and is most suitable as a highly public power generation facility.

[Brief description of the drawings]

FIG. 1 is a system diagram showing a half of one embodiment of the present invention.

FIG. 2 is a system diagram showing the other half of one embodiment of the present invention.

FIG. 3 is a system diagram showing a conventional means for performing intake cooling of a gas turbine by utilizing cold heat of LNG.

FIG. 4 is a system diagram showing a conventional LNG vaporizer.

[Explanation of symbols]

(1) First heat medium evaporator (1a), (12a), (39a) Heat transfer tube group (A) Heat medium (2), (10) Body (3) First LNG
Vaporizer (3a), (4a), (11a) U-shaped tube group (4) Second LNG
Vaporizer (5) Heat medium vapor conduit (5i) Heat medium vapor supply port (5θ) Heat medium vapor discharge port (6) Heat medium conduit (6i) Heat medium supply port (6θ) Heat medium discharge port (7) LNG supply Pipe (7i), (8i), (9i) LNG supply port (8), (9) LNG conduit (8θ), (9θ) LNG discharge port (11) Third LNG
Vaporizer (12) Second heat medium evaporator (13) Vaporized NG conduit (13θ) Vaporized NG outlet (14) LNG flow controller (14a) LNG flow detector (14b) LNG flow control valve (15) ) LNG flow signal selector (16a), (16b)
Controller (17) Water flow signal selector (18) Water flow controller (18a) Water flow detector (18b) Water flow control valve (19) Gas turbine intake duct (19i) Air inlet (19θ) ) Air outlet (20) Inlet cooler (20a) Heat transfer tube group with fins (21) Gas turbine equipment (21a) Air compressor (21b) Combustor (21c) Gas turbine (22), (23), (24) ), (26) Water conduit (27), (28), (29), (32) Water conduit (33), (35), (36), (38) Water conduit (22i), (23i) ), (24i) Water supply port (33i), (35i) Water supply port (22θ), (23θ), (24θ) Water discharge port (32θ), (35θ) Water discharge port (25) Inlet cooling water circulation pump ( 30), (37) Temperature detection
Controllers (30a), (30b), (37a) Flow control valve (37b) Flow control valve (31) Power plant equipment (34) Station cooling water circulation pump (39) Station cooling water cooler (40), ( 41) Seawater conduit

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroshi Makihara 4-6-22 Kannonshinmachi, Nishi-ku, Hiroshima City Inside Hiroshima Research Laboratory, Mitsubishi Heavy Industries, Ltd. (72) Inventor Keijiro Yoshida 2-5-1 Marunouchi, Chiyoda-ku, Tokyo No. Mitsubishi Heavy Industries, Ltd. (72) Inventor Haruki Yajima 2-1-1, Shinhama, Arai-machi, Takasago City, Hyogo Prefecture Inside Mitsubishi Heavy Industries, Ltd. Takasago Works (56) References JP-A-6-229258 (JP, A) JP-A-7-119487 (JP, A) JP-A-6-42369 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F02C 7/143 F17C 9/02

Claims (6)

(57) [Claims] 1. An LNG vaporizer for heating LNG with a heat medium vapor across a metal wall and cooling and condensing the heat medium vapor; heating the heat medium liquid cooled and condensed by the LNG vaporizer with water A heat medium evaporator for generating the heat medium vapor and cooling the water; and cooling the gas turbine intake of the natural gas-fired gas turbine combined cycle power plant with the water cooled by the heat medium evaporator. An intake air cooler; an in-plant cooling water cooler for cooling water for cooling the power plant equipment with seawater; and a water after cooling the power plant equipment in the in-plant cooling water cooler. A pipe connecting the water outlet of the in-house cooling water circulation pump to the water inlet of the in-house cooling water cooler; and the power plant equipment by bypassing the in-house cooling water cooler with the water outlet of the in-house cooling water circulation pump. Communicate with kind A pipe connecting a water outlet of the intake air cooler to a water inlet of the heat medium evaporator; and a pipe connecting a water outlet of the in-house cooling water circulation pump to a water inlet of the heat medium evaporator. A pipe connecting the water outlet of the heat medium evaporator to the water inlet of the intake air cooler; and cooling at least one of the water outlet of the heat medium evaporator and the water outlet of the air intake cooler. An LNG vaporizer for fuel of a natural gas-fired gas turbine combined cycle power plant, comprising: a pipeline communicating with at least one of a water inlet and a water outlet of a water cooler. 2. The fuel for a natural gas-fired gas turbine combined cycle power plant according to claim 1, wherein the heat medium is 1,2,2,2-detrafluoroethane [HFC-134a]. LNG vaporizer. 3. The power generation system, wherein a water outlet of the in-house cooling water circulation pump communicates with a water inlet of the in-house cooling water cooler and a water outlet of the in-house cooling water circulation pump bypasses the in-house cooling water cooler. An in-plant cooling water temperature control flow control valve provided in at least one of the pipelines communicating with the equipment at the station, and a temperature detector for detecting the temperature of water for cooling the equipment at the power plant. 3. The natural gas-fired fuel according to claim 1 or 2, further comprising: means for adjusting an opening of the flow rate control valve for adjusting the temperature of the in-site cooling water based on a value detected by the temperature detector. LNG vaporizer for fuel of gas turbine combined cycle power plant. 4. A pipe connecting the water outlet of the intake air cooler to a water inlet of the heat medium evaporator and a pipe connecting the water outlet of the in-house cooling water circulation pump to the water inlet of the heat medium evaporator. A flow control valve for adjusting the temperature of water supplied to the heat medium evaporator provided in at least one of the heat medium evaporators, a temperature detector for detecting the temperature of water supplied to the heat medium evaporator, and a detection value of the temperature detector 4. A natural gas-fired gas turbine according to claim 1, further comprising means for adjusting an opening degree of the flow rate control valve for adjusting the temperature of the supply water of the heat medium evaporator based on the flow rate. LNG vaporizer for fuel of combined cycle power plant. 5. A first heat medium evaporator housed in the liquid phase portion in a first heat medium evaporator body having a heat medium vapor phase in an upper portion and a heat medium liquid phase in a lower portion. Installed at a position higher than the installation position of the first heat medium evaporator, the upper part is connected by a conduit communicating with the heat medium vapor phase in the first heat medium evaporator body, and the lower part is (1) First LNG housed in a body connected by a conduit communicating with a heat medium liquid phase in a body of a heat medium evaporator
A vaporizer and a second LNG vaporizer; a third LNG vaporizer housed in a heat medium vapor phase portion at an upper portion of the body in which the heat medium is sealed;
A second heat medium evaporator accommodated in a lower heat medium liquid phase portion in the body in which the heat medium is sealed; and a pipe connecting an LNG outlet of the first LNG vaporizer to an LNG inlet of the second LNG vaporizer. The LNG outlet of the second LNG vaporizer is connected to the third LNG
A conduit communicating with an LNG inlet of the G vaporizer; a conduit communicating a water inlet of the second heat medium evaporator with a water outlet of the intake air cooler and a water outlet of the in-house cooling water circulation pump; (2) a pipe connecting the water outlet of the heat medium evaporator to the water inlet of the first heat medium evaporator; and a pipe connecting the water outlet of the first heat medium evaporator to the water inlet of the intake air cooler. The LNG vaporizer for fuel of a natural gas-fired gas turbine combined cycle power plant according to any one of claims 1, 2, 3 and 4, characterized by comprising: 6. A pressure detection / controller for detecting a pressure in the first heat medium evaporator and outputting a control signal,
A water flow signal selector for inputting an output signal of a controller and a demand signal of a water supply amount and outputting a smaller one of them as a water supply amount setting signal; and the first heat medium evaporator A water flow detector for detecting the flow rate of water supplied to the water flow controller, and a water flow controller for inputting a detection signal of the water flow detector and an output signal of the water flow signal selector to output a water flow control signal Water supply amount control means comprising: a water supply amount control valve to the first heat medium evaporator controlled by an output signal of the water flow controller; and a pressure in the first heat medium evaporator. A pressure detection / controller that detects and outputs a control signal, and an output signal of the pressure detection / controller and a demand signal of the LNG supply amount, and the smaller one of the signals is used as the LNG supply amount. An LNG flow signal selector for outputting as a setting signal of An LNG flow detector for detecting a flow rate of LNG supplied to the LNG vaporizer; an LNG flow rate for inputting a detection signal of the LNG flow rate detector and an output signal of the LNG flow rate selector to output an LNG flow rate control signal An LNG supply amount control means including a controller and an LNG flow control valve provided at an LNG inlet of the first LNG vaporizer and controlled by an output signal of the LNG flow controller is provided. An LNG vaporizer for fuel of a natural gas-fired gas turbine combined cycle power plant according to claim 5.