JP2011098154A - Disaster prevention shut-off system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a disaster prevention shut-off system, lightening load of maintenance and besides reinforcing a disaster prevention function such as earthquake resistance by simple construction. <P>SOLUTION: This disaster prevention shut-off system 20 in a LNG receiving base includes: a disaster prevention shut-off valve 22 disposed in an LNG pipe 21; a closing device 23 for closing the disaster prevention shut-off valve 22; and a driving source 24 of the closing device 23. The closing device 23 includes: a turbine chamber 27 housing a turbine 26 rotated by a stream; a transmission means 28 for transmitting the turning force of the turbine 26; a rotary blade 29 rotated with the rotation of the turbine 26 by the transmission means 28; and a closing mechanism 30 for transmitting the turning force of the rotary blade 29 to close the disaster prevention shut-off valve 22. The driving source 24 includes: a branch pipe 35 diverging from a fire extinguishing pipe 34 for fire extinguishing water provided in the LNG receiving base and connected to the turbine chamber 27; and a solenoid valve 36 provided in the branch pipe 35. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a disaster prevention cutoff system in an LNG receiving terminal.

In recent years, at LNG (liquefied natural gas) receiving terminals, new facilities have been added along with the aging and narrowing of existing facilities. In the future, since the demand for LNG tends to increase, many new facilities are expected to be added.
By the way, new facilities are designed to be seismic based on new standards, and are therefore constructed to have sufficient seismic resistance. However, existing facilities do not always meet the new standards, and therefore there is a demand for higher earthquake resistance.

For example, conventionally, LNG pipes that flow LNG are particularly flammable. Therefore, shut-off valves are installed in the LNG pipes at predetermined intervals, and these shut-off valves are closed at the time of disasters such as earthquakes. Prevention has been made in advance (see, for example, Patent Document 1).
By the way, an actuator is required to automatically close the shut-off valve. However, in existing equipment, a power cable for operating the actuator, an instrumentation compressor, and an optical fiber network for measurement are not installed. That is, in the existing equipment, electrical wiring used as signals is installed, but a large-capacity power cable that can be used as power, a compressor having a large capacity, and the like are not installed. And even if it is going to install these newly, there is a problem of the point of cost and an installation place, and it is the present condition that it cannot install easily.

  Against this background, in recent years, a manual shut-off valve in existing equipment has been proposed in which an air motor as an actuator is attached instead of the manual operation handle. This air motor is configured to open a manual valve by rotating a turbine. As a drive source for rotating the turbine, nitrogen gas is mainly used because LNG has a very low temperature and water freezes. In that case, since existing equipment is not usually equipped with nitrogen piping, a nitrogen cylinder is used as a nitrogen gas source, that is, a drive source. Moreover, about the operation, this is operated remotely by providing an electromagnetic valve.

JP-A-62-237175

  By the way, in the shut-off valve with an air motor using a nitrogen cylinder as a drive source, it is necessary to replace the nitrogen cylinder once a year for maintenance, for example. That is, although it is unlikely that nitrogen will actually be released from the cylinder to a predetermined pressure or lower, such replacement is essential to ensure reliability in order to ensure reliable operation in an emergency. However, such a replacement is very burdensome when the number of shut-off valves is large and therefore the number of nitrogen cylinders is large.

  As a drive source, dry air can be used instead of nitrogen.However, since the capacity of the instrumentation compressor is small in existing facilities, it is usually used for air motors that require a large amount of air in an emergency. Not applied. In addition, it is very difficult to install a new compressor having a large capacity due to cost and installation location.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a disaster prevention shut-off system that can reduce a maintenance burden and can reinforce a disaster prevention function such as earthquake resistance with simple construction. There is.

The disaster prevention cutoff system of the present invention is a disaster prevention cutoff system in an LNG receiving base,
A disaster prevention shutoff valve provided in the LNG pipe, a closing device for closing the disaster prevention shutoff valve to shut off the LNG pipe, and a drive source of the closing device,
The closing device includes a turbine chamber that houses a turbine that is rotated by a water flow, a transmission unit that transmits a rotational force of the turbine, a rotary blade that rotates with the rotation of the turbine by the transmission unit, and the rotary blade And a closing mechanism that transmits the rotational force of and closes the disaster prevention shut-off valve,
The drive source includes a branch pipe that branches from a fire extinguishing pipe for a fire extinguishing water provided in the LNG receiving base and connects to the turbine chamber, and an electromagnetic valve provided in the branch pipe. It is said.

  According to this disaster prevention shut-off system, the drive source is configured by using the fire extinguishing pipes that are indispensable for disaster prevention at the LNG receiving terminal. Therefore, compared with the conventional case where a nitrogen cylinder is used as the drive source, maintenance is performed. The disaster prevention function such as earthquake resistance can be reinforced by performing simple construction on the existing manual shut-off valve. Further, by configuring the electromagnetic valve so that it can be remotely operated, the disaster prevention shut-off valve can be closed by remote operation from a control center or the like in the event of a disaster such as an earthquake.

Moreover, the said disaster prevention interruption | blocking system WHEREIN: It is preferable that the said transmission means consists of the permanent magnet provided in the said turbine, and the permanent magnet provided in the said rotary blade.
In this way, since the rotational force of the turbine can be transmitted to the rotor blades without mechanically connecting the rotor blades to the turbine, it is easy to form a turbine chamber that houses the turbine watertight. Become. Therefore, there is no risk that the water leaks and the water freezes and the disaster prevention shut-off valve malfunctions.

Moreover, in the disaster prevention cutoff system, it is preferable that the disaster prevention cutoff valve is provided with a manual operation handle for manually opening the disaster prevention cutoff valve.
If it does in this way, a disaster prevention shut-off valve can be easily opened manually using an operation handle at the time of restoration.

  In the disaster prevention shutoff system of the present invention, the burden of maintenance is greatly reduced, and disaster prevention functions such as earthquake resistance can be reinforced by performing simple construction on existing manual shutoff valves. Therefore, the initial cost required for installation and the running cost required for maintenance can be sufficiently reduced. In addition, the disaster prevention shut-off valve can be closed by remote operation in the event of a disaster such as an earthquake, so that the operation can be performed reliably and high reliability can be obtained.

It is a schematic block diagram of the LNG receiving base which concerns on this invention. It is a schematic structure figure of one embodiment of a disaster prevention interception system of the present invention.

Hereinafter, the disaster prevention interruption system of the present invention will be described in detail.
First, an LNG receiving base according to the present invention will be described with reference to FIG. As shown in FIG. 1, in this LNG receiving base, LNG transported by an LNG ship 1 from an overseas LNG storage base is stored in an LNG tank 3 through an LNG pipe (LNG receiving mother pipe) 2.

A part of the stored LNG is sent to the LNG pipe 5 by the LNG pump 4, vaporized by the vaporizer 6, and then transported to the consumption place 8 such as a factory through the conduit 7. The conduit 7 is branched to the vent stack 9 side. In an emergency, the LNG vaporized by the vaporizer 6 is flowed to the vent stack 9 side and is released into the atmosphere.
The remainder of the LNG sent to the LNG pipe 5 by the LNG pump 4 is filled in the LNG lorry 10 and shipped to a consumer area.

A part of the LNG stored in the LNG tank 3 is guided to the LNG pipe 11, and a part of the LNG is returned to the LNG ship 1 through the return gas blower 12 as a return gas. .
Another part of the LNG guided to the LNG pipe 11 is transported to the consumption place 8 via a BOG (boil-off gas) compressor 14 or sent to the vent stack 9.

The other part of the LNG guided to the LNG pipe 11 is flowed to the flare stack 15 where it is burned.
In such an LNG receiving base, the LNG pipe 2, the LNG pipe 5, the LNG pipe 11, etc. are each provided with a shut-off valve (not shown) for disaster prevention such as an earthquake at every predetermined interval. .

  In the LNG receiving base having such a configuration, when new facilities are added to existing facilities, for example, when the LNG pipe 2, the LNG pipe 5, and the LNG pipe 11 are extended, the existing equipment connected to the new equipment For the LNG pipe 2, the LNG pipe 5, the LNG pipe 11, and the like, it is desired to reinforce disaster prevention as described above so that the earthquake resistance satisfies a new earthquake resistance standard, for example.

  Therefore, in the present invention, a disaster prevention cutoff valve is newly provided in the piping such as the LNG pipe 2, the LNG pipe 5, the LNG pipe 11, or the like, or a disaster prevention cutoff system is constructed using an existing disaster prevention cutoff valve.

  FIG. 2 is a diagram showing an embodiment of the disaster prevention / blocking system of the present invention, and reference numeral 20 in FIG. 2 denotes the disaster prevention / blocking system. The disaster prevention shutoff system 20 includes a disaster prevention shutoff valve 22 provided in the LNG pipe 21 such as the LNG pipe 2, the LNG pipe 5, the LNG pipe 11 and the like, and shuts the LNG pipe 21 by closing the disaster prevention shutoff valve 22. A closing device 23 and a drive source 24 of the closing device 23 are provided.

  The disaster prevention shut-off valve 22 is a low-temperature specification equipped with a butterfly valve 22a, which closes the LNG pipe 21 by closing the butterfly valve 22a and stops the flow of liquefied LNG flowing through the LNG pipe 21. It is. The disaster prevention shut-off valve 22 is provided with a manual operation handle 25 for manually opening the disaster prevention shut-off valve 22 separately from an automatic closing device 23 described later.

  The closing device 23 rotates with the rotation of the turbine 26 by the turbine 26 rotated by the water flow, the turbine chamber 27 accommodating the turbine 26, the transmission means 28 for transmitting the rotational force of the turbine 26, and the transmission means 28. A rotary blade 29 and a closing mechanism 30 for closing the disaster prevention shut-off valve 22 are provided.

  The turbine 26 has a plurality of blade portions 26a that receive a water flow and a back plate 26b provided on one side of the blade portions 26a, and is rotatably supported by the turbine chamber 27. It is configured to rotate in response to a water flow supplied from a branch pipe described later. The turbine 26 is provided with a first permanent magnet 28a constituting the transmission means 28 on the back side of each of the plurality of back plates 26b.

  The turbine chamber 27 accommodates the turbine 26 therein and is rotatably supported by the turbine chamber 27. The turbine chamber 27 is connected to a branch pipe described later and further connected to a drain pipe 31. The drain pipe 31 is supplied to the turbine chamber 27 and is used for transferring the water flow after rotating the turbine 26 to a drainage facility (not shown) and discharging it there. The turbine chamber 27 is formed not only in its interior but also in a watertight connection with the branch pipe and the drain pipe 31 so that the water supplied to the turbine chamber 27 does not leak outside. Yes.

  The rotary blade 29 is disposed on the side of the turbine chamber 27 and is rotatably supported on a side plate 27a of the turbine chamber 27, and has a plurality of blade portions 29a. Each of the blade portions 29 a is provided with a second permanent magnet 28 b constituting the transmission means 28 on the side facing the back surface of the back plate 26 b of the turbine 26. The second permanent magnet 28b constitutes the transmission means 28 together with the first permanent magnet 28a, and the first permanent magnet 28a and the second permanent magnet 28b are attracted to each other or repel each other. Thus, the rotational force of the turbine 26 is transmitted to the rotary blades 29, and the rotary blades 29 are also rotated along with the rotation of the turbine 26.

  The closing mechanism 30 is provided on the first gear 32 provided on the shaft portion 29 b of the rotary blade 29 and the rotating shaft 22 b of the butterfly valve 22 a of the disaster prevention cutoff valve 22, and meshes with the first gear 32. And a second gear 33. Under such a configuration, when the rotary blade 29 rotates and the first gear 32 rotates, the opening / closing mechanism 30 transmits the rotational force to rotate the second gear 33 to rotate the butterfly valve 22a. The disaster prevention shutoff valve 22 is closed by turning.

  The drive source 24 includes a branch pipe 35 that branches from the fire extinguishing pipe 34 for the fire extinguishing water and connects to the turbine chamber 27, and an electromagnetic valve 36 provided in the branch pipe 35. It is. The fire extinguishing pipe 34 is indispensable for disaster prevention at the LNG receiving terminal, and the water pressure is constantly compensated to a predetermined value or more in preparation for disasters such as earthquakes. The electromagnetic valve 36 normally shuts off the branch pipe 35 and stops the flow of water from the fire extinguishing pipe 34 through the branch pipe 35 to the turbine chamber 27.

  The solenoid valve 36 is operated by an electric signal sent from a general 100V power source installed in the existing equipment without requiring a large-capacity power cable for operating the actuator. The operation is configured to be controlled by remote operation. That is, this electromagnetic valve 36 is electrically connected to, for example, a control center, and can be opened by a remote operation from here in the event of a disaster such as an earthquake.

In the disaster prevention shut-off system 20 having such a configuration, the closing device 23 does not operate because the electromagnetic valve 36 is normally closed. Therefore, the disaster prevention shut-off valve 20 is in an open state, and the inside of the LNG pipe 21 is The liquefied LNG flows.
When a disaster such as an earthquake occurs, the solenoid valve 36 is opened by remote control from a control center or the like.

  Then, since the water pressure of the fire extinguishing pipe 35 is constantly supplemented to a predetermined value or more, the water flow enters the turbine chamber 27 through the branch pipe 35 and rotates the turbine 26. When the turbine 26 rotates in this manner, the first permanent magnet 28a provided in the turbine 26 and the second permanent magnet 28b of the rotor blade 29 disposed outside the turbine chamber 27 are attracted to each other. Alternatively, the rotating blades 29 are also rotated by repelling each other.

When the rotary blade 29 rotates in this way, the first gear 32 that constitutes the closing mechanism 30 rotates, and the second gear 33 that meshes therewith also rotates, so that the butterfly valve 22a also rotates, and disaster prevention The shut-off valve 22 is closed. Therefore, the flow of LNG flowing through the LNG pipe 21 is interrupted, whereby the outflow of LNG from the LNG pipe 21 is prevented.
At the time of recovery after such a disaster such as an earthquake has ended, the solenoid valve 36 is closed, and the operation handle 25 is manually operated to close the butterfly valve 22a.

  In this disaster prevention system 1, since the drive source 24 is configured by using the fire extinguishing pipe 34 that is indispensable for disaster prevention at the LNG receiving base, a nitrogen cylinder is used as the drive source as in the past. Compared to the above, the maintenance burden can be greatly reduced, and the running cost can be greatly reduced. In addition, disaster prevention functions such as earthquake resistance can be reinforced by performing simple construction to add the drive source 24 and the closing device 23 to the manual shut-off valve provided in the existing equipment. The required initial cost can be sufficiently reduced. Furthermore, the electromagnetic valve 36 is configured so that it can be operated remotely, so that the disaster prevention shut-off valve 22 can be closed by remote control from a control center or the like in the event of a disaster such as an earthquake. Reliability can be ensured.

In addition, the disaster prevention cutoff system 1 of this invention is not limited to the said embodiment, In the range which does not deviate from the summary of this invention, it can change suitably. For example, the configuration of the closing mechanism 30 and the configuration of the transmission means 28 are not limited to the configuration using the pair of gears 32 and 33 or the configuration using the first and second permanent magnets 28a and 28b. Various conventionally known configurations can be employed.
Further, the LNG receiving base is not limited to the one shown in FIG. 1, and therefore the LNG pipe 21 provided with the disaster prevention shutoff valve 22 shown in FIG. 2 is also used in the LNG pipes 2, 5, 11 shown in FIG. The present invention can be applied to various LNG pipes arranged at other locations.

  DESCRIPTION OF SYMBOLS 20 ... Disaster prevention cutoff system, 21 ... LNG piping, 22 ... Disaster prevention cutoff valve, 23 ... Closing device, 24 ... Drive source, 25 ... Operation handle, 26 ... Turbine, 27 ... Turbine room, 28 ... Transmission means, 29 ... Rotary blade 30 ... Closing mechanism, 32 ... First gear, 33 ... Second gear, 34 ... Fire extinguishing pipe, 35 ... Branch pipe, 36 ... Solenoid valve

Claims (3)

A disaster prevention system at an LNG receiving terminal,
A disaster prevention shutoff valve provided in the LNG pipe, a closing device for closing the disaster prevention shutoff valve to shut off the LNG pipe, and a drive source of the closing device,
The closing device includes a turbine chamber that houses a turbine that is rotated by a water flow, a transmission unit that transmits a rotational force of the turbine, a rotary blade that rotates with the rotation of the turbine by the transmission unit, and the rotary blade And a closing mechanism that transmits the rotational force of and closes the disaster prevention shut-off valve,
The drive source includes a branch pipe that branches from a fire extinguishing pipe for a fire extinguishing water provided in the LNG receiving base and connects to the turbine chamber, and an electromagnetic valve provided in the branch pipe. Disaster prevention system.   The disaster prevention and interruption system according to claim 1, wherein the transmission means includes a permanent magnet provided on the turbine and a permanent magnet provided on the rotor blade.   The disaster prevention cutoff system according to claim 1 or 2, wherein the disaster prevention cutoff valve is provided with a manual operation handle for manually opening the disaster prevention cutoff valve.

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