JPH11210990A - Lng receiving device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a simple device to feed gas in a tank in a ship and to shorten a piping to feed gas. SOLUTION: This LNG receiving device comprises tanks 2 and 3 to store LNG; an LNG unloading line 26 to unload LNG from a LNG ship 1 to the tanks 2 and 3; and an LNG extraction line 40 to extract and vaporize the LNG fed through the LNG unloading line 26 and return it as LNG vaporize gas to the LNG ship 1. The LNG extraction line 4 may comprise a control unit 41 to reduce a pressure and regulate extracted LNG; and a vaporizer 42 to vaporize pressure-reduced LNG to produce gas.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an LN
The present invention relates to an LNG receiving device that receives and stores G as a liquid.

[0002]

2. Description of the Related Art FIG. 2 shows a conventional receiving device for receiving LNG (liquefied natural gas) and the receiving device for receiving LNG.
1 shows a power generator using NG. As the receiving device, an underground tank 2 and an above-ground tank 3 are provided, and a loading arm 19 is provided on a pier 14 to which the LNG ship 1 berths, for connecting a pipe on the ground with an alloying tool 25 of the LNG ship 1. The loading arm 19 includes a liquid loading arm 19a for transferring LNG and a gas loading arm 19b for transferring LNG vaporized gas. The liquid loading arm 19a and the underground tank 2 and the above-ground tank 3 are connected by an LNG unloading line 26.

[0003] The LNG stored in the underground tank 2 and the above-ground tank 3 is partially vaporized into gas by the rise in temperature in the tank. Each of the tanks 2 and 3 is provided with a vaporized gas extracting line 28 for extracting the vaporized gas. The gas compressor 5 is provided in the vaporized gas extraction line 28, and the vaporized gas is guided to the boiler 7 and burned there. The return gas blower 4 is provided in the vaporized gas take-out line 28, and a part of the vaporized gas is returned to the LNG ship 1 via the gas loading arm 19b.

[0004] The LNG ship 1 is provided with an inboard tank 18 for loading LNG, and the inboard tank 18 is provided with an LNG pump 15 for sending out LNG. The LNG pump 15 and an alloying tool 25 for the liquid loading arm 19a are provided.
Are connected by an LNG extraction line 23. The top of the inboard tank 18 and the gas loading arm 1
9b is connected to the alloy tool 25 by a gas return line 24.

[0005] Next, the LNG reception to the LNG receiving device will be described. When the LNG ship 1 is moored on the pier 14, the loading arms 19a, 1 for fluid and gas are provided.
9 b is connected to the alloy 25 of the LNG ship 1. The LNG pump 15 of the onboard tank 18 is operated to transfer the LNG from the LNG unloading line 26 to the underground tank 2 and the above-ground tank 3. In the two tanks 2 and 3, LNG is constantly vaporized gently, so that the gas is sucked by the gas compressor 5 of the vaporized gas extraction line 28 and sent to the boiler 7. LN
The return gas blower 4 is operated in parallel with the operation of the LNG pump 15 of the Vessel G, and the LNG vaporized gas is supplied in accordance with the decrease of the LNG in the onboard tank 18, so that the internal pressure of the onboard tank 18 is maintained substantially constant.

[0006]

SUMMARY OF THE INVENTION Return gas blower 4
Has a large external shape and installation area, and the price of the equipment is high. Also,
The distance from the underground tank 2 and the above-ground tank 3 to the gas loading arm 19b provided on the pier 14 is usually 1 km or more, and a gas pipe for gas transfer is required during this time.

[0007] The present invention has been made in view of such problems, and by providing a simple device for sending gas to an onboard tank, the piping for sending this gas can be shortened.
The aim is to reduce equipment and make effective use of the site.

[0008]

In order to achieve the above object, according to the first aspect of the present invention, a tank for storing LNG,
An LNG unloading line for unloading LNG from the LNG ship to the tank; and extracting LNG from the LNG unloading line and vaporizing the LNG into LNG vaporized gas and returning it to the LNG ship.
An NG extraction line.

[0009] LNG of the LNG ship is transferred to a tank by an LNG unloading line. The LNG extraction line is
Connect to G unloading line, extract and vaporize LNG
Return to the LNG ship as G gas. Extraction position is LNG
By placing the ship near the pier where the ship is moored, the length of the gas pipe for sending the vaporized gas to the LNG ship can be shortened, and at the same time, the equipment can be reduced and the site can be effectively used.

[0010] In the second aspect of the present invention, the LNG extraction line includes a pressure regulating valve for regulating the pressure of the extracted LNG, and a vaporizer for vaporizing the reduced LNG to produce gas.

Since LNG is easily gasified by exchanging heat with seawater or the like, a small-sized vaporizer that fills an onboard tank can be manufactured at a lower cost than a blower such as a return blower. Further, since the LNG unloading line is pressurized by the LNG liquid pump in the ship, the gas outlet pressure of the vaporizer can be controlled to an appropriate pressure to be sent into the ship by the control unit.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below.
This will be described with reference to the drawings. FIG. 1 shows an LNG receiving device of the present embodiment and a power generating device for gasifying the received LNG and generating power. The LNG receiving device takes out the LNG vaporized gas in the underground tank 2 and the above-ground tank 3 for storing LNG (generally, there are a plurality of these and there is often only one type), and the boiler 2 7, a gas compressor 5, a small vaporizer 42 that extracts LNG unloaded from the LNG ship 1 and converts it into gas, an LNG onboard tank 1
8, a pressure gauge 41a for measuring the pressure of the gas sent to 8, a liquid loading arm 19a for connecting the piping of the LNG ship 1 to the piping of the tanks 2 and 3, and a gas loading arm 19b.
Having. The LNG ship 1 is unloaded and moored on a dedicated pier 14. The pier 14 has a loading arm 19a for liquid,
The gas loading arm 19b and the small vaporizer 42 are arranged.

The LNG ship 1 usually has a plurality of inboard tanks 18, each inboard tank 18 having an LNG pump 15, an LNG extraction line 23 connected thereto, and an LNG onboard tank by partially returning LNG gas and extracting LNG. A gas return line 24 for preventing a change in the tank internal pressure of 18 is provided. The LNG take-out line 23 is connected to the liquid loading arm 19a, and the gas return line 24 is connected to the gas loading arm 19b by a metal alloy tool 25. Has become.

An LNG unloading line 26 is provided connecting the liquid loading arm 19a and each of the tanks 2 and 3,
LNG is transferred to each of tanks 2 and 3. A vaporized gas take-out line 28 is provided to connect the top of each of the tanks 2 and 3 with the gas compressor 5, and feeds the LNG vaporized gas vaporized in the tanks to the boiler 7. Underground tank 2 has L near the bottom of the tank.
An NG pump 15 is provided, and an LNG pump 15 is provided in the ground tank 3 near the bottom outside the tank.
The LNG is transferred to the large vaporizer 6 via the G transfer line 27.

LNG unloading line 26 branches off LN
A G extraction line 40 is provided and connected to the gas loading arm 19b. The branch point P is located near the pier 14, and the length of the gas pipe to the gas loading arm 19b is shortened. The LNG extraction line 40 is provided with a control unit 41 and a small vaporizer 42. The vaporizer 42 is a device that raises the temperature of the low-temperature LNG with seawater or the like and vaporizes the LNG.
It is suitable for the ship's LNG tank capacity.
Is much smaller than the vaporizer 6 that vaporizes LNG. Therefore, the vaporizer 42 is relatively compact as a device and can be installed on the pier 14. By installing the vaporizer 42 on the pier 14 in this way, it is not necessary to provide a relatively large site for installing the return blower near the tanks 2 and 3 as in the conventional case, and the space can be reduced.
Further, since the branch point P is installed near the pier 14, the length of the LNG extraction line 40 is much shorter than the length of the gas pipe from the conventional tanks 2, 3 to the gas loading arm 19b.

The vaporizer 6 is a device for raising the temperature of LNG transferred from each of the tanks 2 and 3 by seawater and vaporizing the LNG, and has a much larger capacity than the vaporizer 42 described above. The vaporized LNG is combined with the LNG vaporized gas from the gas compressor 5 and sent to the boiler 7. The steam generated in the boiler 7 is sent to the turbine 8 by the steam line 33, rotates the turbine, and rotates the generator 9 directly connected to the turbine shaft to generate power. The generated electricity enters the transformer 10 by the electric wire 34 and is boosted to a high voltage for power transmission.
The power is transmitted to the consumer by the power transmission device 12 from here.

A seawater pump 16 for sucking seawater is provided in the vicinity of the quay, and the sucked seawater is supplied to the seawater supply line 3.
At 0, it is sent to the condenser of the turbine 8. The seawater heated by the condenser is returned to the sea again by the seawater discharge line 31, but a part of the seawater enters the seawater line for vaporization 32 by the seawater pump 17. In the vaporizer 6, LNG is vaporized with the heated seawater to LNG vaporized gas. The LNG vaporized gas is sent to the burner 22 of the boiler 7 by a gas supply line 29.

The combustion furnace of the boiler 7 is provided with a burner 22, an air passage 35 for blowing air, and a flue gas passage 36 for discharging flue gas. An air blower 20 is provided at the inlet of the air passage 35, and the air
Is provided with an air preheater 21 for preheating air and cooling combustion exhaust gas. The cooled combustion exhaust gas is discharged from the chimney 13.

Next, the operation of the LNG receiving device will be described. When the LNG ship 1 is moored on the pier 14, the alloying tool 25 mounted on the ship side and the loading arms 19a, 1
The alloying tool 25 on the 9b side is joined. The LNG pump 15 in the inboard tank 18 is operated to transfer the LNG to the underground tank 2 or the ground tank 3 through the liquid loading arm 19a and the LNG unloading line 26. At the same time, the control unit 41 is adjusted to reduce the pressure to a pressure suitable for the vaporizer 42, and the vaporizer 42 generates LNG vaporized gas corresponding to the pressure sent to the LNG onboard tank 18. Send in. Since the pressure in the inboard tank 18 is about 1000 mmAq and the length of the gas pipe between the vaporizer 42 and the inboard tank 18 is short, the gas vaporized by the inflation pressure when vaporizing without using a blower is used. Can be sent to In this way, the LNG vaporized gas corresponding to the volume of the transferred LNG is supplied to the onboard tank 18,
The tank internal pressure can be kept almost constant.

[0020]

As described above, according to the present invention, a part of LNG is extracted from the LNG unloading line, vaporized and returned to the onboard tank, so that a return gas blower is not required. No area is required. The extraction position is L
The gas pipe length can be significantly reduced by being near the mooring pier of the NG ship.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of an LNG receiving device and a power generating device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a conventional LNG receiving device and a power generation device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 LNG ship 2 Underground tank 3 Above-ground tank 4 Return gas blower 5 Gas compressor 6 Vaporizer 7 Boiler 8 Turbine 9 Generator 10 Transformer 11 Switchyard 12 Power transmission device 13 Chimney 14 Pier 15 LNG pump 16 Seawater intake pump 17 Seawater pump Reference Signs List 18 Inboard tank 19a Liquid loading arm 19b Gas loading arm 22 Burner 23 LNG extraction line 24 Gas return line 25 Aluminum alloy tool 26 LNG unloading line 27 LNG transfer line 28 Vaporized gas extraction line 29 LNG vaporized gas supply line 30 Seawater Supply line 31 Seawater discharge line 32 Seawater line for vaporization 33 Steam line 40 LNG extraction line 41 Control unit 41a Pressure gauge 42 Vaporizer

Claims (2)

[Claims] 1. An LNG storage tank, an LNG unloading line for unloading LNG from the LNG ship to the tank, and LNG extracted and vaporized from the LNG unloading line into LNG vaporized gas. An LNG receiving device comprising: an LNG extraction line for returning to an LNG ship. 2. The method according to claim 1, wherein the LNG extraction line includes an extracted LN.
2. The LNG receiving device according to claim 1, further comprising: a pressure adjusting valve for adjusting the pressure of G, and a vaporizer for evaporating the reduced LNG into gas.