JPH09166291A - Storage equipment for low temperature liquefied gas - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a storage equipment for low temperature liquefied gas formed so that vaporized gas in a storage tank of the low temperature liquefied gas can be effectively utilized in a base of LNG or the like, and capable of safely coping with power service interruption in the base. SOLUTION: The storage equipment comprises a storage tank 1 of low temperature liquefied gas, gas turbine 11 connecting rotary shafts to each other, generator 12, BOG compressor 13, draw out pipe 5 introducing BOG (vaporized gas) generated in the storage tank 1 relating to the BOG compressor 13, fuel gas introducing pipe line 25 introducing BOG compressed in the compressor 13 to the gas turbine 11 as fuel gas and a tank 20 storing high pressure gas for starting/accelerating the gas turbine 11 and the compressor 13.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a storage facility for low temperature liquefied gas such as LNG and LPG.

[0002]

2. Description of the Related Art In this type of storage equipment, BOG (Boil Off Gas) is generated in a storage tank, so that it is necessary to treat the BOG as needed in order to keep the pressure in the tank constant. In conventional equipment, usually an electric BOG
It is equipped with a compressor that compresses BOG with this compressor.
It is processed by mixing it with the city gas or the gas supply line to the power plant.

FIG. 2 shows the structure of a conventional low-temperature liquefied gas storage facility. The reference numeral 1 in the figure is a storage tank,
A low temperature liquefied gas such as LNG or LPG is stored inside. The storage tank 1 is connected to a lead-out conduit 3 for sending the low-temperature liquefied gas to the vaporizer 2 by a delivery pump 9, and the delivery side of the vaporizer 2 is a feed for delivering the vaporized gas to a supply destination. The gas line 4 is connected. Also,
The storage tank 1 has a BOG generated inside the storage tank 1.
The gas extraction pipe 5 for extracting the
A BOG compressor 7 driven by an electric motor 6 for compressing the BOG to raise the pressure to a predetermined pressure is installed in the. The outlet side of the BOG compressor 7 is connected to the feed gas line 4 via a pipe line 8 so that the BOG boosted by the BOG compressor 7 can be joined to the feed gas line 4. .

[0004]

By the way, in recent years, the BOG compression pressure when mixed in the feed gas line 4 tends to increase in response to a request for increasing the gas pressure at the supply destination. Therefore, it is necessary to increase the capacity of the BOG compressor 7, that is, the capacity of the electric motor 6 accordingly.
However, to improve the capacity of the BOG compressor 7, B
Attempting to merge the OG with the feed gas line 4 causes an unreasonable increase in cost. In addition, when the demand at the destination decreases for some reason, or when there is a situation in which the electric motor 6 of the BOG compressor 7 cannot be operated due to a total power outage at a base such as LNG, processing of the required amount of BOG is performed. However, there was a problem that the pressure in the storage tank 1 was increased.

In view of the above circumstances, the present invention enables the evaporative gas in the storage tank for the low temperature liquefied gas to be effectively used in the base such as LNG, so that it is possible to safely handle the power failure even in the base. An object of the present invention is to provide a storage facility for low temperature liquefied gas.

[0006]

According to a first aspect of the present invention, a storage tank for a low temperature liquefied gas, a gas turbine generator and a compressor whose rotating shafts are directly connected to each other, and a storage tank for the compressor are generated. And a means for introducing the vaporized gas compressed by the compressor as a fuel gas into the gas turbine, and a means for activating and increasing the speed of the gas turbine and the compressor. .

The invention of claim 2 is characterized in that the means for accelerating and accelerating the gas turbine comprises a high-pressure gas tank for storing high-pressure gas for accelerating and activating.

According to a third aspect of the present invention, there is provided a bypass valve for adjusting the outlet pressure by bypassing the inlet side and the outlet side of the compressor.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to FIG. In FIG. 1, the same functional elements as those of the conventional equipment of FIG. 2 are designated by the same reference numerals and the description thereof will be omitted. FIG. 1 shows a low-temperature liquefied gas storage facility 1 according to an embodiment.
The structure of 0 is shown. In this storage facility 10, a gas turbine 11, a generator 12, and a centrifugal BOG compressor 13 whose rotating shafts are directly connected to each other are provided instead of the conventional electric BOG compressor. The gas turbine 11 is provided with an air compressor 14 that generates high-pressure air mixed with combustion gas.

An outlet pipe 21 of the high pressure gas tank 20 is connected to the inlet side of the gas turbine 11 via an opening / closing valve A. This high-pressure gas tank 20 is a gas turbine 1
1 and the BOG compressor 13 as a start-up and speed-up means, and high-pressure gas for start-up and speed-up is stored inside. As the high-pressure gas for starting and accelerating, the feed gas line 4
The high-pressure gas, the high-pressure gas at the time of boosting the BOG compressor 13, the high-pressure gas of another highly compressible BOG compressor, and the like may be introduced. A stop valve E is provided in the introduction line.

The outlet side of the gas turbine 11 is connected to the inlet side of the BOG compressor 13 via an opening / closing valve B, and is also connected to an exhaust pipe line 22 in which the opening / closing valve C is inserted. An inlet side of the BOG compressor 13 is further connected to a BOG outlet pipe (means for introducing evaporative gas) 5 of the storage tank 1, and an outlet side of the BOG compressor 13 is connected to a fuel gas introducing pipe line in which an opening / closing valve D is inserted. 25 through the gas turbine 11
It is connected to a combustion adjusting mechanism 23 provided on the inlet side of the. Further, a bypass valve PC for adjusting the pressure on the outlet side is provided between the inlet side and the outlet side of the BOG compressor 13.

Next, the operation will be described. Here, the case where the system shown in the figure is provided as an emergency facility will be described. First, high pressure gas is stored in the high pressure gas tank 20 for normal operation and for acceleration. Then, when it becomes necessary to drive this system, the opening / closing valve A and the opening / closing valve B are opened. Then, the high-pressure gas for startup and acceleration is introduced from the high-pressure gas tank 20 into the gas turbine 11, and the gas turbine 11 rotates and accelerates.
As a result, the BOG compressor 13 also starts rotating.

After the gas turbine 11 is accelerated, the high pressure gas introduced from the high pressure gas tank 20 is used for the gas turbine 1
Ignition 1 After ignition, the open / close valve C is opened and the open / close valve B is closed. When the BOG compressor 13 is driven by the ignition of the gas turbine 11, the BOG from the storage tank 1
(For example, gas pressure = 0.1 kg / square centimeter)
Is compressed and is increased to a predetermined pressure (20 kg / cm 2) required for combustion in the gas turbine 11 in accordance with the speed increase of the BOG compressor 13. BOG compressor 13
When the outlet pressure of is at the specified value, open the on-off valve D,
The gas turbine 11 is operated at the rated operation, and after the rated operation, electric power is taken out by the generator 12. The combustion exhaust gas from the gas turbine 11 is released into the atmosphere through the exhaust pipe line 22. When the rated operation is reached, the on-off valve A is closed. Further, the bypass valve PC is adjusted according to the BOG processing amount, the fuel gas amount and the gas pressure to the gas turbine 11 are adjusted, and the power generation amount is changed.

In this way, once the gas turbine 11 and the BOG compressor 13 are started and accelerated, the BOG compressor 1
3 compresses the BOG and sends it to the gas turbine 11. On the other hand, the gas turbine 11 drives the BOG compressor 13 by the driving force generated by the combustion energy of gas, and the surplus power causes the generator 12 to generate power. Therefore, as long as the gas turbine 11 is started up and accelerated, the BOG compressor 13 and the gas turbine 11 start the self-sustaining operation, and the BOG is automatically burnt in the gas turbine 11 and the surplus power is used for power generation. As a result, the BOG is effectively used.

[0015]

As described above, according to the first aspect of the invention, the gas turbine generator and the compressor are directly connected to each other, and the gas turbine is operated by using the evaporated gas (BOG) compressed by the compressor as fuel. Since the compressor is driven by the power generated by the gas turbine and the power is generated by the surplus power of the gas turbine, once the gas turbine and the compressor are started and accelerated, when the demand of the gas supply destination decreases, Even in the case of a total power failure of a base such as LNG, the required amount of BOG can be reliably burned and processed, and the BOG can be effectively used to obtain electric power. Therefore, the safety of bases such as LNG can be improved. In addition, since it is possible to effectively use BOGs in bases such as LNG, BOGs tailored to demand
There is no need to increase the capacity of the compressor, and the increase in cost can be prevented.

If a high-pressure gas tank for starting and speeding up is provided as in the second aspect of the invention, the structure is simplified,
By adjusting the inlet pressure to the gas turbine with the bypass valve as in the third aspect of the invention, it becomes possible to easily cope with the amount of BOG generated.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a low-temperature liquefied gas storage facility according to an embodiment of the present invention.

FIG. 2 is a configuration diagram of a conventional low-temperature liquefied gas storage facility.

[Explanation of symbols]

 1 Storage Tank 5 BOG Extraction Pipe (Means for Introducing Evaporative Gas) 11 Gas Turbine 12 Generator 13 BOG Compressor 20 High Pressure Gas Tank (Start-Up / Raising Means) 25 Fuel Gas Introduction Pipeline (Means for Introducing Fuel Gas)

Claims (3)

[Claims] 1. A low-temperature liquefied gas storage tank, a gas turbine generator and a compressor whose rotating shafts are directly connected to each other, a means for introducing the evaporative gas generated in the storage tank to the compressor, and a compressor. A storage facility for low-temperature liquefied gas, comprising: a means for introducing the vaporized gas compressed in 1. into a gas turbine as fuel gas; and a means for activating and accelerating the gas turbine and the compressor. 2. The low-temperature liquefied gas storage facility according to claim 1, wherein the means for activating and accelerating the gas turbine comprises a high-pressure gas tank for storing high-pressure gas for accelerating and activating. 3. The low-temperature liquefied gas storage facility according to claim 1, further comprising a bypass valve that adjusts an outlet pressure by bypassing an inlet side and an outlet side of the compressor.