JP6338519B2 - Portable liquefied natural gas supply equipment - Google Patents

Description

The present invention relates to a portable liquefied natural gas supply facility for evaporating liquefied natural gas and supplying it to a consumer as a gas.

  Natural gas is a naturally occurring fossil fuel and is a hydrocarbon gas mainly composed of methane. The natural gas is mainly used for industrial and power generation gas fuels, and industrial applications tend to increase. Recently, the demand for natural gas has increased in place of heavy oil and kerosene, which are uncertain about the remaining reserves.

  The liquefied natural gas (hereinafter referred to as “LNG”) is obtained by cooling and liquefying the natural gas for the purpose of transporting or storing the natural gas.

  In continents such as North America and China where natural gas production is expected, gas-like natural gas is generally transported and supplied as it is using pipelines. In Japan and other Asian countries where production in neighboring areas is low, natural gas is transported and stored as liquefied LNG.

  The transportation and storage of the LNG are generally performed as follows. First, LNG is transported by sea using a tanker and landed at an LNG receiving terminal (also referred to as “primary base”). Then, it is transported by land to a LNG satellite facility (also referred to as “satellite base”) installed near the place of use by a tank truck for LNG.

  The LNG satellite facility is a facility that combines storage and supply of LNG. The LNG satellite facility generally includes a storage tank, a pressurized evaporator, a vaporizer, and the like.

  The following patent documents 1 and patent documents 2 exist as prior art documents concerning such an LNG satellite facility.

JP 2013-92184 A JP 2007-85403 A

[Problems related to installation work]
When installing the above-mentioned LNG satellite facility, it is required to accurately align pipes and equipment. Examples of the pipe include a pipe for transferring liquid LNG from a storage tank to a vaporizer, and a pipe for supplying gaseous natural gas vaporized by the vaporizer. It is necessary to interpose devices such as a pressure gauge and a flow meter in these pipes. These pipes and equipment must be installed in a state that does not cause gas leakage. For this reason, it is requested | required that the said piping and apparatus should make the alignment precision in a height direction or a horizontal direction high and weld.

  However, the installation work of the LNG satellite facility is generally an outdoor work. Therefore, welding work is also affected by the weather, and it is difficult to work while ensuring accuracy. The same applies to pressure resistance inspection and airtight inspection after assembly. Thus, there is a problem that installation work of the LNG satellite facility takes a great deal of time.

[Patent Document 1]
In the above-mentioned Patent Document 1, a device for reducing the work outdoors is made in the construction of installing the LNG satellite facility.
That is, the above Patent Document 1 has the following disclosure.
[0015] As shown in FIGS. 1 and 2, the LNG satellite facility X of the present embodiment includes a storage tank unit 1 for storing liquefied natural gas (LNG), a vaporization unit 3 for vaporizing LNG, and a piping unit 2. Is installed and fixed at an outdoor installation location.
[0018] The piping unit 2 includes an LNG piping 21 for transferring the LNG from the storage tank unit 1 to the vaporizing unit 3, and a gas piping 22 for passing gaseous natural gas derived from the vaporizing unit 3. Configured.
[0020] In the present embodiment, the piping unit 2 includes a two-stage mount 23 having a lower step portion 23A and an upper step portion 23B, as shown in FIGS. The piping 21 for gas and the piping 22 for gas are incorporated in the mount frame 23. More specifically, the LNG pipe 21 is arranged in the lower stage 23A of the gantry 23, and the gas pipe 22 is arranged in the upper stage 23B of the gantry 23.
[0021] A plate member 231 is provided between the lower step portion 23A and the upper step portion 23B of the gantry 23.

  Although the technique described in Patent Document 1 can shorten the installation time to some extent, it is still necessary to perform much of the assembly work outdoors on the installation site. Therefore, the problem of time-consuming installation work has not been solved.

[Problems related to equipment scale]
LNG satellite facilities are not all the same scale. That is, a large-scale or a small-scale one is installed according to the continuous amount of LNG required by the user. Specifically, the storage tank and supply capacity are designed to be scaled according to the user.

  At this time, when the storage amount of the storage tank becomes 3 t or more, it is obliged to adopt an earthquake-resistant design. Therefore, an LNG satellite facility of this scale must adopt an earthquake-resistant design for the foundation and each part.

  Small and medium-sized users who need less than 3 tons of storage tanks will no longer be required to make earthquake-resistant designs. However, even such a small and medium-sized LNG satellite facility basically adopts a design and configuration conforming to a scale with a storage amount of 3 t or more. In other words, it takes much time for installation work.

[Patent Document 2]
Patent Document 2 discloses a satellite base that is a natural gas small-scale storage and supply facility.
That is, Patent Document 2 has the following disclosure.
[0017] The LNG in the large LNG storage tank 32 is filled in a bulk container 10 to be described later. The bulk container 10 filled with LNG is transported to the unloading pier and loaded on a barge ship (general-purpose ship) 18 by a container crane. A single barge ship 18 is loaded with several to several tens of bulk containers 10 and connected by a container fixing device (not shown) generally used to prevent collapse of cargo. It is fixed to the hull. After the loading is completed, the barge 18 transports the bulk container 10 by sea to the nearest cargo port 22 (receiving port) of the satellite base 24. In the cargo port 22, the container 10 is unloaded using a container crane after the container fixing device is released in the reverse procedure of the loading operation. The bulk container 10 unloaded at the cargo port 22 is transferred to a general trailer 20 used for container transportation and transported to a satellite base 24 which is a liquefied natural gas small-scale storage and supply facility.
[0019] Here, as shown in FIG. 2, the bulk container 10 has a ramen structure in which a bulk container 16 on a substantially elliptic cylinder shape having a heat insulating structure for holding LNG at an ultra-low temperature is formed in a rectangular parallelepiped shape with a steel frame. The container body 34 is fixed in a laid state. The bulk container 16 has the same structure as the tank portion (bulk container) of a conventional tank truck. As can be seen from the figure, a brace of steel frame and a vertical member are attached to the container body 34 for reinforcement. Although the bulk container 16 is contained in the container main body 34, since the whole is not covered, the state can be observed from the outside. On the other hand, since the bulk container 16 is protected by the container body, when the bulk container 10 is mounted on the trailer 20 and transported, even if the trailer 20 is in a traffic accident or the like, The risk of damaging the bulk container 16 can be reduced compared to a tank truck with the container exposed.
[0020] The transported bulk container 10 is temporarily installed in the satellite base 24 as it is (see FIG. 1). The installed bulk container 10 also serves as the LNG tank 6 constructed in each conventional satellite base. Therefore, it is not necessary to construct an LNG tank at each satellite base as in the prior art, and the facilities and operating costs of the satellite base can be reduced.
[0021] For installation of the bulk container at the satellite base, the bulk container 10 lowered from the trailer loading platform may be placed on the base platform provided at the satellite base, and only the bulk container may be used as the LNG tank ( 1), the entire trailer carriage part 42 is cut off as shown in FIG. 1 and fixed to the satellite base 24 using wheels 36 and a support base 38, so that the trailer carriage part 42 and the bulk container 10 are integrated. It may be used as an LNG tank.
[0022] The installed bulk container 10 is connected to the gas pipe 26, and the LNG stored in the bulk container 16 is vaporized by the pressurized evaporator and the LNG vaporizer 8 through the gas pipe 26. To the natural gas utilization facility 28 of the consumer 14.

  However, in the satellite base 24 disclosed in Patent Document 2, facilities such as a pressurized evaporator, an LNG vaporizer 8, and a buffer tank 9 must be installed. Similar to Patent Document 1, such a satellite base 24 basically adopts a design and configuration conforming to a scale with a storage amount of 3 t or more. Therefore, the problem of time-consuming installation work still cannot be solved.

〔the purpose〕
The present invention has been made with the following object in order to solve the above problems.
Providing a portable liquefied natural gas supply facility that greatly simplifies the installation work.

The portable liquefied natural gas supply facility according to claim 1 employs the following configuration in order to achieve the above object.
Vaporization means for vaporizing the liquefied natural gas supplied from the storage tank to obtain natural gas;
A buffer tank for temporarily storing the natural gas vaporized by the vaporization means;
Pressure reducing means for reducing the pressure to supply the natural gas temporarily stored in the buffer tank to the natural gas using facility;
A part of the natural gas temporarily stored in the buffer tank is pressurized with a pressurizing pump and returned to the storage tank, thereby applying pressure when the liquefied natural gas is taken out to the storage tank. Pressurizing means for,
A unit means for making the vaporizing means, the buffer tank, the pressure reducing means, and the pressure means a unit capable of transporting ,
Further, there are different sets of receiving routes for receiving the supply of the liquefied natural gas taken out from the storage tank and delivery routes for sending out the natural gas pressurized by the pressurizing means to return to the storage tank. A plurality of storage tanks are provided to correspond to the storage tanks .

The portable liquefied natural gas supply facility described in claim 2 adopts the following configuration in addition to the configuration described in claim 1.
The pressurizing means includes a pressure accumulator that stores the natural gas pressurized by the pressurizing pump at a necessary pressure.

The invention described in claim 1 includes unit means for making the vaporizing means, the buffer tank, the pressure reducing means, and the pressure applying means a transportable unit.
In this way, by making the liquefied natural gas supply equipment into one unit, work such as piping and equipment installation is done indoors in a good environment to create the unit, and it is transported and installed to the installation site together with the unit. Can do. Most of the work at the installation site can be done by installing the unit on a solid foundation. That is, work such as installation of piping and equipment is not performed outdoors at the installation site, and is not affected by the weather or the like. Thus, the portable liquefied natural gas supply equipment of the present invention can greatly simplify the labor of installation work.

According to the first aspect of the present invention, since the unit is provided with a pressurizing means, the efficiency of replenishing and filling LNG is good. In other words, if there is no pressurizing means, the removal of LNG from the storage tank depends only on the internal pressure of the storage tank. Then, the following two problems occur.
The first is that the LNG in the storage tank cannot be taken out before it runs out, and the next LNG must be replenished. Since the present invention includes the pressurizing means, the next LNG may be replenished after taking out until the LNG in the storage tank runs out.
Second, the internal pressure for taking out LNG from the storage tank is affected by the environmental temperature. For example, it is easy to take out LNG from the storage tank in summer, and it is difficult to take out LNG from the storage tank in winter. Since the present invention includes the pressurizing means, the LNG in the storage tank can be stably taken out without being affected by the environmental temperature.

  According to the first aspect of the present invention, LNG transported using a portable storage tank such as a tank container can be supplied to the installed liquefied natural gas supply facility.

The invention according to claim 1 is a receiving route for receiving the supply of the liquefied natural gas taken out from the storage tank, and a delivery route for sending the natural gas pressurized by the pressurizing means to return to the storage tank. A plurality of sets are provided so as to correspond to different storage tanks .
For this reason, for example, the following operation is possible. When supplying LNG, first, the first portable storage tank is connected to the first receiving route and the first sending route. When the first storage tank runs short, the second portable storage tank is transported, connected to the second receiving route and the second delivery route, and the supply of LNG is started. The first storage tank that has become empty is disconnected and returned to the primary base to replenish LNG. Then, when the second storage tank is low, the first portable storage tank is transported, connected to the first receiving route and the first sending route, and the supply of LNG is started again. . By operating in this way, it is possible to prevent the inconvenience that the supply of LNG temporarily stops due to replacement of the storage tank.

According to a second aspect of the present invention, the pressurizing means includes a pressure accumulator that stores the natural gas pressurized by the pressurizing pump at a necessary pressure.
The said accumulator absorbs that the discharge pressure of the natural gas discharged from a pressurization pump pulsates. Thereby, the stable appropriate pressure can always be given with respect to a storage tank, and LNG in a storage tank can be taken out stably, without receiving influences, such as environmental temperature.

It is a figure explaining mainly the external appearance structure of the portable liquefied natural gas supply equipment of 1st Embodiment of this invention. It is a figure mainly explaining the piping structure of the said 1st Embodiment.

Next, an embodiment for carrying out the present invention will be described.
1 and 2 show a first embodiment of a portable liquefied natural gas supply facility to which the present invention is applied. FIG. 1 is a plan view mainly showing an external structure. FIG. 2 mainly shows the piping structure.

〔overall structure〕
The portable liquefied natural gas supply facility 100 according to the present embodiment includes a vaporization unit 2, a buffer tank 6, a decompression unit 4, a pressurization unit 3, and a unit unit 5. In this portable liquefied natural gas supply facility 100, liquefied natural gas is supplied from the storage tanks 1a and 1b mounted on the tank container 12, and is vaporized and supplied to the natural gas using facility.

[Storage tank]
The storage tanks 1a and 1b constitute a tank container 12 that is mounted on a container table 13 and can be transported. The storage tanks 1a and 1b store liquefied natural gas. As the storage tanks 1a and 1b, a vacuum insulation type tank for storing a low-temperature liquefied gas can be used.

  In the illustrated example, a state in which two storage tanks 1a and 1b are connected to the portable liquefied natural gas supply facility 100 is shown. In other words, the portable liquefied natural gas supply facility 100 transports the second storage tank 1b to the primary base and fills the liquefied natural gas while receiving the supply of liquefied natural gas from the first storage tank 1a. Can come. When the first storage tank 1a becomes empty, supply of liquefied natural gas is started from the second storage tank 1b, and the first storage tank 1a is transported to the primary base and filled with liquefied natural gas. it can. Thus, the liquefied natural gas of the primary base can be continuously supplied to the portable liquefied natural gas supply facility 100 by alternately using the first storage tank 1a and the second storage tank 1b.

  The storage tanks 1a and 1b are provided with liquid take-out paths 33a and 33b and liquid take-out ports 23a and 23b for taking out the liquefied natural gas stored in the storage tanks 1a and 1b. The storage tanks 1a, 1b are pressurized passages for ensuring the internal pressure of the storage tanks 1a, 1b by returning the natural gas pressurized by the pressurizing means 3 into the storage tanks 1a, 1b. 34a, 34b and pressurizing ports 24a, 24b are provided. By the pressurization in the storage tanks 1a and 1b by the pressurizing means 3, the liquefied natural gas is extracted from the liquid extraction paths 33a and 33b. The storage tanks 1a and 1b are provided with a discharge port 11.

  In this example, the tank container 12 is a horizontal type having a length of 9122 mm and a length and width of 2490 mm, respectively. The capacity of the storage tanks 1a and 1b is about 10t. The internal pressure is set to approximately 0.3 to 0.4 MPa.

[Vaporization means]
The vaporizing means 2 vaporizes the liquefied natural gas supplied from the storage tanks 1a and 1b to obtain natural gas.

  In the present embodiment, the vaporizing means 2 includes a hot water tank 18 and a heat exchange unit 19. The hot water tank 18 is filled with hot water from the hot water introduction path 18a. A heat exchanging unit 19 is disposed in the hot water tank 18. The heat exchange unit 19 contacts hot water filled in the hot water tank 18. The heat exchange unit 19 is supplied with liquefied natural gas which has been supplied from the storage tanks 1a and 1b and passed through the liquid passage 19a. Thereby, heat exchange is performed between the hot water filled in the hot water tank 18 and the liquefied natural gas passing through the heat exchanging unit 19, and the liquefied natural gas is vaporized to become natural gas. Natural gas coming out of the heat exchange unit 19 is introduced into the buffer tank 6 through the gas passage 19b. The hot water in the hot water tank 18 that has become water by cooling by the heat exchange is discharged from the drainage channel 18b.

  The generation pressure of the natural gas generated by the vaporization means 2 is, for example, about 0.3 MPa.

[Buffer tank]
The buffer tank 6 temporarily stores the natural gas vaporized by the vaporizing means 2.

  Most of the natural gas stored in the buffer tank 6 is supplied to the decompression means 4 through the supply path 30. A part of the natural gas stored in the buffer tank 6 is taken out from the gas outlet 31 and introduced into the pressurizing means 3.

  The storage pressure of the natural gas stored in the buffer tank 6 is, for example, about 0.3 MPa.

[Pressure reduction means]
The decompression means 4 decompresses the natural gas temporarily stored in the buffer tank 6 in order to supply the natural gas to the facility using the natural gas.

  The pressure reducing means 4 includes a pressure reducing valve provided in the supply path 30. The supply pressure of the natural gas supplied to the natural gas using facility via the decompression means 4 is set to about 0.1 MPa, for example.

[Pressure means]
The pressurizing means 3 pressurizes a part of the natural gas temporarily stored in the buffer tank 6 by pressurizing pumps 7a and 7b and returns the compressed gas to the storage tanks 1a and 1b, thereby storing the storage tank 1a. , 1b for applying a pressure when taking out the liquefied natural gas.

  In this example, the pressurizing means 3 includes two pressurizing pumps 7a and 7b arranged in parallel. The pressurizing means 3 includes a pressure accumulator 8 that stores the natural gas pressurized by the two pressurizing pumps 7a and 7b at a necessary pressure. As the two pressure pumps 7a and 7b, for example, diaphragm pumps can be used. This is because natural gas, which is a flammable gas, can be safely pressurized. The pressure accumulator 8 absorbs the pulsation of the discharge pressure of the natural gas discharged from the diaphragm type pressure pumps 7a and 7b. As a result, the natural gas can be returned to the storage tanks 1a and 1b with a stable pressure, and the pressure in the storage tanks 1a and 1b can be kept within a certain range. Thereby, the liquefied natural gas in the storage tanks 1a and 1b can be taken out in a stable state.

  By returning the natural gas by the pressurizing means 3, the internal pressure of the pressurized storage tanks 1a and 1b can be set to 0.3 to 0.4 MPa, for example.

[Connection with storage tank]

  In the present embodiment, the storage tanks 1a and 1b receive the natural gas pressurized by the pressurizing means 3 and the receiving routes 21a and 21b for receiving the supply of the liquefied natural gas taken out from the storage tanks 1a and 1b. A plurality of sets of sending routes 22a and 22b that are sent out to return to the above are provided. In the illustrated example, two sets of receiving routes 21a and 21b and sending routes 22a and 22b are provided. Two storage tanks 1a and 1b can be arranged according to this number.

  The receiving routes 21a and 21b are composed of receiving ports 14a and 14b for receiving liquefied natural gas, and receiving paths 15a and 15b for sending the received liquefied natural gas to the liquid path 19a. The liquefied natural gas sent to the liquid path 19a is introduced into the heat exchange unit 19 of the vaporizing means 2.

  The inlets 14a and 14b are connected to the liquid outlets 23a and 23b of the storage tanks 1a and 1b by flexible hoses 25b. Thereby, the liquefied natural gas in the storage tanks 1a and 1b passes through the liquid take-out passages 33a and 33b, the liquid take-out ports 23a and 23b, the flexible hose 25b, the receiving ports 14a and 14b, the receiving passages 15a and 15b, and the liquid passage 19a. Then, it is introduced into the heat exchange part 19 of the vaporizing means 2.

  The delivery routes 22a and 22b are composed of delivery paths 17a and 17b and delivery ports 16a and 16b for communicating natural gas in communication with the accumulator 8 of the pressurizing means 3.

  The delivery ports 16a and 16b are connected to the pressurization ports 24a and 24b of the storage tanks 1a and 1b by a flexible hose 25a. Thereby, the natural gas stored in the pressure accumulator 8 of the pressurizing means 3 passes through the delivery paths 17a and 17b, the delivery ports 16a and 16b, the flexible hose 25a, the pressurization ports 24a and 24b, and the pressurization paths 34a and 34b. Are introduced into the storage tanks 1a and 1b.

[Purge gas]
This embodiment includes a purge gas purge gas cylinder 27 for purging the inside of the flexible hoses 25a and 25b, and a buffer tank 26 for temporarily storing the purge gas taken out from the purge gas cylinder 27. The purge gas delivered from the buffer tank 26 purges the pressure ports 24a and 24b from the purge passage 28 through the delivery passages 17a and 17b, the delivery ports 16a and 16b, and the flexible hose 25a. The purge gas sent out from the buffer tank 26 purges the liquid outlets 23a and 23b from the purge passage 28 through the receiving passages 15a and 15b, the inlets 14a and 14b, and the flexible hose 25b. Thereby, flexible hose 25a, 25b can be removed safely. For example, nitrogen gas can be used as the purge gas. A part of the purge gas is also used for instrumentation such as valve opening and closing operations.

[Unit means]
The unit means 5 is a unit capable of transporting the vaporizing means 2, the buffer tank 6, the decompressing means 4 and the pressurizing means 3.

  In this example, the unit means 5 is a rectangular base to which the vaporizing means 2, the buffer tank 6, the pressurizing means 3, the decompressing means 4, the purge gas cylinder 27, and the like are attached. On the unit means 5, the vaporizing means 2, the buffer tank 6, the purge gas cylinder 27 and the like are mounted and fixed. Necessary piping and equipment such as the pressurizing means 3 and the decompressing means 4 are connected.

[Operation]
In the portable liquefied natural gas supply facility of this embodiment, the vaporizing means 2, the buffer tank 6, the pressurizing means 3, and the decompressing means 4 are configured as one unit. This unit is manufactured indoors in a factory, and the completed unit is transported to the user's site as it is and installed.

The portable liquefied natural gas supply equipment of this embodiment is operated as follows, for example.
The tank container 12 is filled with LNG at the primary base, the tank container 12 is transported, and the LNG is transported to the portable liquefied natural gas supply equipment 100 in each place by land transport, or by using land transport and railway together. The transported tank container 12 is connected to the portable liquefied natural gas supply facility 100 by the flexible hoses 25a and 25b, and the liquefied natural gas is supplied to the portable liquefied natural gas supply facility 100. In the portable liquefied natural gas supply facility 100, the liquefied natural gas is vaporized and supplied to the utilization facility.

  The portable liquefied natural gas supply facility 100 transports the second storage tank 1b to the primary base and fills the liquefied natural gas while receiving the supply of the liquefied natural gas from the first storage tank 1a. . When the first storage tank 1a becomes empty, the supply of liquefied natural gas is started from the second storage tank 1b, and the first storage tank 1a is transported to the primary base and filled with liquefied natural gas. The first storage tank 1a and the second storage tank 1b are alternately used to supply the liquefied natural gas at the primary base to the portable liquefied natural gas supply facility 100 continuously.

  In this embodiment, by using the buffer tank 6 and the diaphragm type pressurizing pumps 7a and 7b, a safe pressure adjustment is possible. In addition, by using a plurality of separation / portable tank containers 12 on the storage side, the LNG user can use the tank continuously without worrying about the remaining amount of the storage tank. That is, the remaining amount in the storage tank due to the consumption of LNG does not affect the user's business activities using LNG.

[Effect of the embodiment]
This embodiment has the following effects.

The present embodiment includes unit means 5 that makes the vaporizing means 2, the buffer tank 6, the decompressing means 4, and the pressurizing means 3 a transportable unit.
In this way, by making the liquefied natural gas supply equipment into one unit, work such as piping and equipment installation is done indoors in a good environment to create the unit, and it is transported and installed to the installation site together with the unit. Can do. Most of the work at the installation site can be done by installing the unit on a solid foundation. That is, work such as installation of piping and equipment is not performed outdoors at the installation site, and is not affected by the weather or the like. Thus, the portable liquefied natural gas supply facility 100 of the present invention can greatly simplify the labor of installation work.

In the present embodiment, since the pressure unit 3 is provided in the unit, the efficiency of LNG replenishment and filling is good. That is, if the pressurizing means 3 is not provided, the removal of LNG from the storage tanks 1a and 1b depends only on the internal pressure of the storage tanks 1a and 1b. Then, the following two problems occur.
The first is that the LNG in the storage tanks 1a and 1b cannot be taken out before it runs out, and the next LNG must be replenished. Since the present invention includes the pressurizing means 3, it is only necessary to take out the LNG in the storage tanks 1a and 1b until there is no more LNG and then replenish the next LNG.
Second, the internal pressure for taking out LNG from the storage tanks 1a and 1b is affected by the environmental temperature. For example, in summer, it is easy to take out LNG from the storage tank, and in winter, it is difficult to take out LNG from the storage tanks 1a and 1b. Since the present invention includes the pressurizing means 3, the LNG in the storage tanks 1a and 1b can be stably taken out without being affected by the environmental temperature.

  The present embodiment can also supply LNG transported using, for example, portable storage tanks 1a and 1b such as a tank container 12 to the installed liquefied natural gas supply equipment.

In the present embodiment, the storage tanks 1a and 1b receive the natural gas pressurized by the pressurizing means 3 and the receiving routes 21a and 21b for receiving the supply of the liquefied natural gas taken out from the storage tanks 1a and 1b. A plurality of sets of delivery routes 22a and 22b that are sent out to return to the corresponding storage tanks 1a and 1b are provided .
For this reason, for example, the following operation is possible. When supplying LNG, first, the first portable storage tank 1a is connected to the first receiving route 21a and the first sending route 22a. When the first storage tank 1a is low, the second portable storage tank 1b is transported and connected to the second receiving route 21b and the second sending route 22b, and the supply of LNG is started. To do. The empty first storage tank 1a is disconnected and returned to the primary base to replenish LNG. When the second storage tank 1b is low, the first portable storage tank 1a is transported and connected to the first receiving route 21a and the first sending route 22a, and again the LNG Start supplying. By operating in this way, it is possible to prevent the inconvenience that the supply of LNG temporarily stops due to the replacement of the storage tanks 1a and 1b.

In the present embodiment, the pressurizing means 3 includes a pressure accumulator 8 that stores the natural gas pressurized by the pressurizing pumps 7a and 7b at a necessary pressure.
The accumulator 8 absorbs the pulsation of the discharge pressure of the natural gas discharged from the pressurizing pumps 7a and 7b. As a result, a stable and appropriate pressure can always be applied to the storage tanks 1a and 1b, and the LNG in the storage tanks 1a and 1b can be stably taken out without being affected by the environmental temperature or the like.

[Modification]
The above has described a particularly preferred embodiment of the present invention. However, the present invention is not intended to be limited to the illustrated embodiment, and can be implemented by being modified in various aspects, and the present invention includes various modifications. This is the purpose.

DESCRIPTION OF SYMBOLS 1a: 1st storage tank 1b: 2nd storage tank 2: Vaporization means 3: Pressurization means 4: Pressure reduction means 5: Unit means 6: Buffer tank 7a: Pressure pump 7b: Pressure pump 8: Pressure accumulator 11 : Discharge port 12: Tank container 13: Container stand 14a: Receiving port 14b: Receiving port 15a: Receiving channel 15b: Receiving channel 16a: Outlet port 16b: Outlet port 17a: Outlet channel 17b: Outlet channel 18: Hot water tank 18a: Hot water Introduction path 18b: Drainage path 19: Heat exchange section 19a: Liquid path 19b: Gas path 21a: Reception route 21b: Reception route 22a: Delivery route 22b: Delivery route 23a: Liquid outlet 23b: Liquid outlet 24a: Pressurization port 24b: Pressurizing port 25a: Flexible hose 25b: Flexible hose 26: Buffer tank 27: Purge gas cylinder 28: Purge path 30: Supply path 3 : Gas extraction path 33a: Liquid extraction path 33b: Liquid extraction path 34a: pressurization channels 34b: pressurization channels 100: portable liquefied natural gas supply system

Claims (2)

Vaporization means for vaporizing the liquefied natural gas supplied from the storage tank to obtain natural gas;
A buffer tank for temporarily storing the natural gas vaporized by the vaporization means;
Pressure reducing means for reducing the pressure to supply the natural gas temporarily stored in the buffer tank to the natural gas using facility;
A part of the natural gas temporarily stored in the buffer tank is pressurized with a pressurizing pump and returned to the storage tank, thereby applying pressure when the liquefied natural gas is taken out to the storage tank. Pressurizing means for,
A unit means for making the vaporizing means, the buffer tank, the pressure reducing means, and the pressure means a unit capable of transporting ,
Further, there are different sets of receiving routes for receiving the supply of the liquefied natural gas taken out from the storage tank and delivery routes for sending out the natural gas pressurized by the pressurizing means to return to the storage tank. A portable liquefied natural gas supply facility characterized in that a plurality of storage tanks are provided so as to correspond to storage tanks . The portable liquefied natural gas supply facility according to claim 1, wherein the pressurizing means includes a pressure accumulator that stores the natural gas pressurized by the pressure pump at a necessary pressure.

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