JP7316068B2 - Floating equipment and manufacturing method for floating equipment - Google Patents

Description

TECHNICAL FIELD The present disclosure relates to a floating facility and a method of manufacturing a floating facility.

Liquefied natural gas (LNG) is typically stored in a cryogenic liquid state at about -160°C. Therefore, methods have been proposed for effectively utilizing the cold energy of LNG.

For example, Patent Literature 1 describes a cryogenic power generator that uses LNG cold heat to generate electricity. More specifically, the cryogenic power generator described in Patent Document 1 uses a heat medium cooled by heat exchange with LNG as a cold heat source, and uses exhaust gas from a main combustion engine that uses LNG as a heat source to generate heat. Including cycles. An expansion turbine provided on the heat cycle drives a generator to generate power.

JP 2014-104847 A

By the way, a floating storage and regasification unit (FSRU) equipped with LNG storage tanks and regasification equipment on a floating body is used for LNG storage and regasification as well as land-based LNG receiving terminals. It is used by anchoring it fixedly at a pier or the like. However, the above-mentioned cryogenic power generation using the cold energy of LNG usually uses large-scale equipment, so in such floating equipment, there are problems such as space restrictions on the floating body and equipment installation costs. Therefore, cold power generation has not been introduced. Therefore, in the floating facility, it is required to introduce cold power generation to improve energy efficiency.

In view of the above circumstances, it is an object of at least one embodiment of the present invention to provide a floating facility capable of improving energy efficiency and a method for manufacturing the floating facility.

(1) Floating equipment according to at least one embodiment of the present invention,
a floating body;
an LNG tank provided on the floating body;
a first heat exchanger for vaporizing the liquefied natural gas from the LNG tank by heat exchange with a heat medium to obtain regasified LNG;
an expansion turbine that satisfies the following conditions (A) or (B);
Prepare.
(A) configured to be driven by said regasified LNG from said first heat exchanger;
(B) The first heat exchanger forms part of a thermodynamic cycle utilizing the liquefied natural gas as a low temperature heat source and is driven by the gaseous heat medium.

As used herein, "regasified LNG" means gas obtained by heating and vaporizing liquefied natural gas (LNG) in a heat exchanger.

According to the configuration (1) above, in a floating facility (FSRU) capable of storing and regasifying liquefied natural gas stored in an LNG tank, cold heat of LNG stored in the LNG tank provided on the floating body can be used to drive an expansion turbine. Therefore, by driving the power generator with the expansion turbine, it becomes possible to generate power using the cold heat of LNG, and the energy efficiency of the floating facility as a whole can be improved.

Note that the expansion turbine that satisfies the above condition (A) may be one that can be used as a turbine (for example, a steam turbine, etc.) as a main engine for generating the propulsion force of the floating body. In this case, an LNG tanker (carrier) having a turbine that can be used as a main engine can be operated as a floating LNG storage and regasification unit (FSRU). Therefore, the operation of the floating facility can be switched between the LNG tanker and the FSRU, for example, according to the demand for LNG, thereby efficiently using the floating facility.

(2) In some embodiments, in the configuration of (1) above,
The floating facility is
It further comprises an internal combustion engine configured to be able to supply liquefied natural gas from the LNG tank.

According to the above configuration (2), an LNG tanker (carrier) having an internal combustion engine that can be used as a main engine can be operated as a floating LNG storage and regasification unit (FSRU). Therefore, the operation of the floating facility can be switched between the LNG tanker and the FSRU, for example, according to the demand for LNG, thereby efficiently using the floating facility.
Further, according to the above configuration (2), when the floating facility is operated as an FSRU, power generation by the internal combustion engine can be performed in addition to power generation by the expansion turbine. Therefore, it is possible to flexibly adjust the power generation amount according to the power demand in the floating facility.

(3) In some embodiments, in the configuration of (2) above,
The expansion turbine satisfies the condition (A),
The heat medium includes cooling water after cooling the internal combustion engine.

According to the above configuration (3), the cooling water of the internal combustion engine is used as a heat medium to regasify the LNG from the LNG tank, so the exhaust heat of the internal combustion engine is effectively used and efficient It is possible to generate power at

(4) In some embodiments, in the configuration of any one of (1) to (3) above,
The expansion turbine satisfies the condition (A),
The floating facility is
a high-pressure turbine having an outlet portion that can communicate with an inlet side of the expansion turbine and including turbine blades that are shorter than the expansion turbine;
an introduction line configured to introduce the regasified LNG directly into the expansion turbine without passing through the high pressure turbine.

The volumetric flow rate of the fluid supplied to the turbine may differ depending on whether the turbine is used as a main engine or the like during operation as an LNG tanker or as an expansion turbine for power generation during operation as an FSRU. In this regard, the expansion turbine of (4) above is a turbine configured to be supplied with fluid having a lower pressure than the fluid supplied to the high pressure turbine. That is, in the above configuration (4), in the floating unit (FSRU), the regasified LNG is introduced from the middle stage of the turbine, so the volume flow zone in the expansion turbine is changed from that during operation as an LNG tanker. easy to match. Therefore, it is possible to appropriately drive the expansion turbine in the floating facility.

(5) In some embodiments, in the configuration of any one of (1) to (4) above,
The expansion turbine satisfies the condition (A),
The floating facility is
a low-pressure turbine having an inlet portion communicable with the outlet side of the expansion turbine and including turbine blades longer than the expansion turbine;
a discharge line configured to discharge the regasified LNG from the expansion turbine without passing through the low pressure turbine.

The expansion turbine of (5) above is a turbine configured to be supplied with fluid having a higher pressure than the fluid supplied to the low-pressure turbine. That is, in the above configuration (5), since the regasified LNG is discharged from the middle stage of the turbine in the floating unit (FSRU), the volumetric flow zone in the expansion turbine is changed from that during operation as an LNG tanker. easy to match. Therefore, it is possible to appropriately drive the expansion turbine in the floating facility.

(6) In some embodiments, in the configuration of any one of (1) to (5) above,
The expansion turbine satisfies the condition (A),
the expansion turbine includes a first turbine and a second turbine having a lower inlet pressure than the first turbine;
said first turbine is configured to be supplied with said regasified LNG from said first heat exchanger;
The floating facility is
further comprising a second heat exchanger for heating the regasified LNG discharged from the first turbine;
The second turbine is configured to be supplied with the regasified LNG from the second heat exchanger.

In the configuration (6) above, the expansion turbine has a structure of a reheat turbine including a first turbine and a second turbine to which heated fluid is supplied after being discharged from the first turbine. Therefore, for example, when a reheat turbine is used as a main engine in an LNG tanker, the reheat turbine can be used as an expansion turbine during operation as an FSRU with its structure as it is. Therefore, it is possible to efficiently generate power using the cold energy of LNG while suppressing equipment costs.

(7) In some embodiments, in the configuration of (1) or (2) above,
The expansion turbine satisfies the condition (B),
The floating facility is
a condenser provided downstream of the expansion turbine on the thermodynamic cycle for condensing the heat medium;
a pump provided downstream of the condenser on the thermodynamic cycle for boosting the pressure of the heat medium;
an evaporator provided downstream of the pump on the thermodynamic cycle for evaporating the heat medium;
The condenser includes the first heat exchanger configured to condense the heat medium by exchanging heat with the liquefied natural gas.

According to the above configuration (7), in the floating facility, it is possible to drive the expansion turbine on the thermodynamic cycle using the LNG from the LNG tank provided on the floating body as a low-temperature heat source. That is, the expansion turbine is supplied with the heat medium, which is the working fluid of the thermodynamic cycle, rather than the LNG-derived gas from the LNG tank. Therefore, it is possible to generate power using cold heat of LNG while avoiding leakage of LNG from the expansion turbine.
In addition, according to the configuration of (7) above, the pressure of the heat medium in the thermodynamic cycle can be set regardless of the gas supply pressure of the regasified LNG (supply pressure to the demand destination), so a wide range of LNG Applicable to air supply pressure.

(8) In some embodiments, in the configuration of (7) above,
The floating facility is
An internal combustion engine configured to be able to supply fuel gas derived from the liquefied natural gas stored in the LNG tank,
The evaporator is configured to evaporate the heat medium using exhaust heat of the internal combustion engine.

According to the above configuration (8), since the exhaust heat of the internal combustion engine is used as a high-temperature heat source for evaporating the heat medium (working fluid) in the thermodynamic cycle, the exhaust heat of the internal combustion engine is effectively used. It is possible to efficiently generate power while

(9) In some embodiments, in the configuration of (7) or (8) above,
The floating facility is
An internal combustion engine configured to be able to supply fuel gas derived from the liquefied natural gas stored in the LNG tank,
The internal combustion engine is configured to be supplied with the regasified LNG from the first heat exchanger as fuel.

According to the above configuration (9), the LNG regasified by heat exchange with the heat medium in the first heat exchanger as the condenser in the thermodynamic cycle is supplied as fuel to the internal combustion engine. , the floating facility can be operated efficiently.

(10) In some embodiments, in the configuration of (1) or (2) above,
The expansion turbine satisfies the condition (B),
The floating facility is
a first cooler provided downstream of the expansion turbine on the thermodynamic cycle for cooling the heat medium;
a compressor provided downstream of the first cooler on the thermodynamic cycle for compressing the heat medium;
a heater provided downstream of the compressor on the thermodynamic cycle for heating the heat medium;
The first cooler includes the first heat exchanger configured to cool the heat medium by heat exchange with the liquefied natural gas.

According to the above configuration (10), in the floating facility, it is possible to drive the expansion turbine on the thermodynamic cycle using the LNG from the LNG tank provided on the floating body as a low-temperature heat source. That is, the expansion turbine is supplied with the heat medium, which is the working fluid of the thermodynamic cycle, rather than the LNG-derived gas from the LNG tank. Therefore, it is possible to generate power using cold heat of LNG while avoiding leakage of LNG from the expansion turbine.
In addition, in the case of an LNG tanker equipped with a turbine or compressor, the above configuration (10) can be obtained by forming a thermodynamic cycle using existing equipment (turbine or compressor). Therefore, it is possible to efficiently generate power using the cold energy of LNG while suppressing equipment costs.

(11) In some embodiments, in the configuration of (10) above,
The floating facility is
further comprising a rotating shaft connecting the expansion turbine and the compressor;
The compressor is configured to be driven by the expansion turbine via the rotating shaft.

According to the configuration (11) above, the compressor and the expansion turbine on the thermodynamic cycle are connected via the rotating shaft. Therefore, in the LNG tanker, when equipment including a compressor and a turbine connected by a rotating shaft (for example, a turbocharger) is used, by forming a thermodynamic cycle using this equipment, the above (10 ) can be obtained. Therefore, it is possible to efficiently generate power using the cold energy of LNG while suppressing equipment costs.

(12) In some embodiments, in the configuration of (10) or (11) above,
The floating facility is
An internal combustion engine configured to be able to supply fuel gas derived from the liquefied natural gas stored in the LNG tank,
The heater is configured to heat the heat medium using exhaust heat of the internal combustion engine.

According to the above configuration (12), since the exhaust heat of the internal combustion engine is used as a high-temperature heat source for heating the heat medium (working fluid) in the thermodynamic cycle, the exhaust heat of the internal combustion engine is effectively used. It is possible to efficiently generate power while

(13) In some embodiments, in the configuration of any one of (10) to (12) above,
an internal combustion engine configured to be able to supply fuel gas derived from the liquefied natural gas stored in the LNG tank;
a second cooler provided between the expansion turbine and the first cooler on the thermodynamic cycle;
The second cooler is configured to cool the heat medium by heat exchange with liquefied natural gas supplied from the LNG tank to the internal combustion engine.

According to the configuration (13) above, the heat medium in the thermodynamic cycle is further cooled by heat exchange with LNG from the LNG tank in the second cooler, so that the cold heat of LNG is used to further cool the heat medium. Power can be generated efficiently.

(14) In some embodiments, in the configuration of any one of (1) to (13) above,
The expansion turbine includes a rotor, a casing that surrounds the rotor, and a seal that suppresses fluid leakage through a gap between the rotor and the casing,
The seal portion is configured to be supplied with an inert gas having a higher pressure than the regasified LNG or the heat medium supplied to the expansion turbine.

According to the above configuration (14), since the inert gas having a higher pressure than the fluid (regasified LNG or heat medium) supplied to the expansion turbine is supplied to the seal portion, for example, the floating facility Even if the operation mode is changed and the type of fluid supplied to the expansion turbine is changed, appropriate shaft sealing can be achieved without changing the structure of the seal portion.

(15) In some embodiments, in the configuration of any one of (1) to (14) above,
The floating facility is
Further comprising a generator configured to be driven by the expansion turbine.

According to the above configuration (15), the cold heat of the LNG stored in the LNG tank provided on the floating body can be used to drive the expansion turbine, and the expansion turbine can drive the generator. can. Therefore, it becomes possible to generate electricity using cold heat of LNG, and it is possible to improve the energy efficiency of the floating facility as a whole.

(16) A method for manufacturing a floating facility according to at least one embodiment of the present invention includes:
a hull;
a main engine provided in the hull;
LNG tanks provided on the hull, and a method for obtaining the floating facility according to any one of claims 1 to 15 by modifying an LNG ship comprising:
providing a first heat exchanger for heat exchange vaporizing the liquefied natural gas in the LNG tank to obtain regasified LNG;
forming a regasified LNG supply line that directs the regasified LNG to a gas facility;
with
The first heat exchanger is configured in relation to the main engine or a turbine forming part of the thermodynamic cycle for waste heat recovery of the main engine so that the expansion turbine functions as an expansion turbine. Satisfy the conditions of (A) or (B).
(A) the expansion turbine is configured to be driven by the regasified LNG from the first heat exchanger;
(B) The first heat exchanger forms a part of a thermodynamic cycle in which the liquefied natural gas is used as a low-temperature heat source, and the expansion turbine is driven by the gaseous heat medium. .

According to the method (16) above, the LNG ship including the turbine that constitutes a part of the main engine or thermodynamic cycle is provided with the first heat exchanger so that the turbine functions as an expansion turbine. By forming a gasification LNG supply line, a floating facility having the configuration (1) above can be manufactured. With the floating facility thus obtained, it becomes possible to generate electricity using the cold heat of LNG, and the energy efficiency of the floating facility as a whole can be improved.

According to at least one embodiment of the present invention, a floating facility capable of improving energy efficiency and a method of manufacturing a floating facility are provided.

1 is a schematic diagram of a floating facility according to one embodiment; FIG. FIG. 2B is a schematic configuration diagram showing an LNG tanker corresponding to the floating facility shown in FIG. 2B; BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic block diagram which shows the floating-body installation which concerns on one Embodiment. FIG. 3C is a schematic configuration diagram showing an LNG tanker corresponding to the floating facility shown in FIGS. 3B and 3C; BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic block diagram which shows the floating-body installation which concerns on one Embodiment. BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic block diagram which shows the floating-body installation which concerns on one Embodiment. FIG. 4B is a schematic configuration diagram showing an LNG tanker corresponding to the floating facility shown in FIG. 4B; BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic block diagram which shows the floating-body installation which concerns on one Embodiment. FIG. 5B is a schematic configuration diagram showing an LNG tanker corresponding to the floating facility shown in FIG. 5B; BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic block diagram which shows the floating-body installation which concerns on one Embodiment. 1 is a schematic diagram of an expansion turbine according to one embodiment; FIG. FIG. 7B is a schematic configuration diagram showing an LNG tanker corresponding to the floating facility shown in FIG. 7B; BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic block diagram which shows the floating-body installation which concerns on one Embodiment. FIG. 8B is a schematic configuration diagram showing an LNG tanker corresponding to the floating facility shown in FIG. 8B; BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic block diagram which shows the floating-body installation which concerns on one Embodiment. FIG. 9B is a schematic configuration diagram showing an LNG tanker corresponding to the floating facility shown in FIG. 9B; BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic block diagram which shows the floating-body installation which concerns on one Embodiment. FIG. 10B is a schematic configuration diagram showing an LNG tanker corresponding to the floating facility shown in FIG. 10B; BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic block diagram which shows the floating-body installation which concerns on one Embodiment. FIG. 11B is a schematic configuration diagram showing an LNG tanker corresponding to the floating facility shown in FIG. 11B; BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic block diagram which shows the floating-body installation which concerns on one Embodiment.

Several embodiments of the present invention will now be described with reference to the accompanying drawings. However, the dimensions, materials, shapes, relative arrangements, etc. of the components described as embodiments or shown in the drawings are not intended to limit the scope of the present invention, and are merely illustrative examples. do not have.

FIG. 1 is a schematic diagram of a floating facility according to one embodiment. The floating facility 100 shown in FIG. 1 is a facility for storing and regasifying LNG (FSRU). The floating facility 100 is obtained, for example, by modifying an LNG tanker 101 (LNG ship) for transporting liquefied natural gas (LNG). In FIG. 1, the elements included in the LNG tanker 101 before remodeling are indicated by solid lines, and the elements added by remodeling are indicated by broken lines.

As shown in FIG. 1 , the LNG tanker 101 before modification includes a hull 2 (floating body), a main engine 4 provided on the hull 2 , and an LNG tank 6 provided on the hull 2 . The hull 2 has a bow 2a having a shape that reduces the resistance the hull receives from fluid such as seawater, and a stern 2b to which a rudder 3 can be attached for adjusting the traveling direction of the hull 2. The main engine 4 is an engine for generating power for driving a propeller 5 as a propulsion device. The LNG tanker 101 shown in FIG. 1 includes an engine 16 as the main engine 4 and a turbine 40 .
The LNG tanker 101 may further include a thermodynamic cycle (eg, Rankine cycle, Brayton cycle, etc.) for recovering exhaust heat from the main engine 4 (eg, engine 16). The thermodynamic cycle will be discussed later.

The floating facility 100 obtained by modifying the LNG tanker 101 described above further includes a first heat exchanger 8 for vaporizing the LNG in the LNG tank 6 by heat exchange, and the cold heat of the LNG. and an expansion turbine 18 . It should be noted that in the exemplary embodiment shown in FIG. 1, turbine 40 functions as expansion turbine 18 . The floating facility 100 also includes a first LNG line 10 for directing LNG from the LNG tank 6 to the first heat exchanger 8 and/or expanding the regasified LNG from the first heat exchanger 8. A second LNG line 12 is provided for leading to the turbine. The floating facility 100 also includes a regasification LNG supply line 14 for guiding the regasification LNG from the expansion turbine 18 to the gas facility (demand destination).

Note that the LNG tanker 101 can also be obtained by modifying the floating facility 100 . That is, the facility including the same hull 2 can be operated as the LNG tanker 101 or as the floating facility 100 (FSRU), and can be operated as the LNG tanker 101 and as the floating facility 100 by remodeling. It is possible to switch between the operation of

Hereinafter, the floating facility 100 and the LNG tanker 101 according to some embodiments will be described more specifically.

2A, 3A, 4A, and 5A (hereinafter also referred to as FIGS. 2A to 5A) each show the LNG tanker 101 before being converted into the floating facility 100 according to one embodiment. It is a schematic block diagram.
FIGS. 2B, 3B, 3C, 4B, and 5B (hereinafter also referred to as FIGS. 2B to 5B) respectively show modifications of the LNG tanker 101 shown in FIGS. 2A to 5A. 1 is a schematic configuration diagram showing a floating facility 100 obtained by
In addition, illustration of the hull 2 (floating body) is abbreviate|omitted in the figure after FIG. 2A.

The LNG tanker 101 shown in FIGS. 2A to 5A is equipped with an engine 16 (internal combustion engine) and a turbine 40 as the main engine 4 . The LNG tanker 101 is also equipped with a boiler 32 for generating steam for driving the turbine 40 .

Boil-off gas from the LNG tank 6 is supplied to the engine 16 and the boiler 32 via a gas supply line 20 . The gas supply line 20 is provided with a compressor 22 for boosting the boil-off gas to an appropriate pressure and a gas header 24 for distributing the gas. The gas supply line 20 branches downstream of the gas header 24 into a first branch line 20 a connected to the boiler 32 and a second branch line 20 b connected to the engine 16 . A valve 30 for adjusting the flow rate of the gas supplied to the boiler 32 is provided in the first branch line 20a.

A generator 28 is connected to the engine 16, and the generator 28 is driven by the engine 16 to generate electric power. The electrical power generated by the generator 28 is sent via the transmission line 56 to the electric motor 66 (see FIG. 3A). The electric motor rotates the propeller 5B (see FIG. 3A) via the gear 58B (see FIG. 3A). In addition, as shown in FIG. 3A, the power transmission line 56 may be appropriately provided with devices such as a transformer 62 and a converter 64 .

The engine 16 may be configured to be able to supply LNG-derived gas (boil-off gas, etc.) as fuel, and to be able to supply oil fuel (for example, light oil) as fuel through the oil supply line 26. .

The boiler 32 is configured to burn the supplied fuel (boil-off gas) and generate steam from the combustion heat. Steam generated by the boiler 32 is supplied to the turbine 40 via a steam supply line 38 . The boiler 32 may be configured to be able to supply LNG-derived gas (boil-off gas, etc.) as fuel, and to be able to supply oil fuel (for example, light oil) as fuel through the oil supply line 36. .

In the exemplary embodiment shown in FIGS. 2A and 4A , a generator 54 is connected to the turbine 40 , the turbine 40 is rotationally driven by steam from the boiler 32 and the generator 54 is driven by the turbine 40 . power is generated by The electrical power so produced, like the electrical power produced by the generator 28 connected to the engine 16, is sent via power lines to the electric motor to drive the propeller 5 via the electric motor. It has become.

In the exemplary embodiment shown in FIGS. 3A and 5A, turbine 40 is connected to propeller 5A via gear 58A. The rotational energy of the rotating shaft of the turbine 40 is transmitted to the propeller 5A via the gear 58A, thereby driving the propeller 5A.

The propeller 5 of the LNG tanker 101 may include a port side propeller 5A and a starboard side propeller 5B. The port side propeller 5A and the starboard side propeller 5B may both be driven by an electric motor 66 (see FIG. 3A). Alternatively, one of the port side propeller 5A and the starboard side propeller 5B may be driven by the electric motor 66 (see FIG. 3A) and the other may be driven by the turbine 40 via gears.

The turbine 40 may also have multiple stages of turbines with different inlet pressures. In the exemplary embodiment shown in FIGS. 2A-5A, the turbines 40 each include a high pressure turbine 42, an intermediate pressure turbine 44 having a lower inlet pressure than the high pressure turbine 42, and a low pressure turbine 44 having a lower inlet pressure than the intermediate pressure turbine 44. a turbine 46;
The high-pressure turbine 42 has an outlet that can communicate with the inlet side of the intermediate-pressure turbine, and includes turbine blades that are shorter than the intermediate-pressure turbine.
The low-pressure turbine 46 has an inlet that communicates with the outlet side of the intermediate-pressure turbine and includes turbine blades that are longer than the intermediate-pressure turbine.

In the exemplary embodiment shown in FIG. 2A, high pressure turbine 42, intermediate pressure turbine 44 and low pressure turbine 46 are arranged on a single axis and are adapted to drive generator 54 via a common rotating shaft.

In the exemplary embodiment shown in FIGS. 3A, 4A and 5A, turbine 40 further includes a reverse turbine 48 . The high pressure turbine 42 and the intermediate pressure turbine 44 arranged on one axis are connected to the generator 54 or the propeller 5A via a common rotating shaft, and the low pressure turbine 46 and the intermediate pressure turbine 46 arranged on the other axis are connected to the propeller 5A through a common rotating shaft. A pressure turbine 44 is connected to the generator 54 or propeller 5A through a common rotating shaft.

In the exemplary embodiment shown in FIGS. 2A-5A, steam from steam supply line 38 is provided to the inlet of high pressure turbine 42 . Also, steam discharged from the high-pressure turbine 42 is supplied to the reheater 34 via a reheater inlet line 50 to be reheated. The reheated steam from the reheater 34 is supplied to the inlet of the intermediate pressure turbine 44 via the reheater outlet line 52 . Steam from the intermediate pressure turbine 44 is supplied to the low pressure turbine 46 . Steam discharged from the low-pressure turbine 46 is returned to the boiler 32 via a condenser (not shown).

In the floating facility (FSRU) 100 shown in FIGS. 2B to 5B, the engine 16 that had the function as the main engine 4 during operation as the LNG tanker 101 (before modification; see FIGS. 2A to 5A) is used. to generate power for use in the floating facility 100 . In addition, by operating the turbine 40 that functions as the main engine 4 during operation as the LNG tanker 101 as the expansion turbine 18, the electric power used in the floating facility 100 is generated.

In the floating facility 100 shown in FIGS. 2B to 5B, boil-off gas from the LNG tank 6 is supplied to the engine 16 via the second branch line 20b of the gas supply line 20, as in the operation as the LNG tanker 101. supplied. A generator 28 is connected to the engine 16, and the generator 28 is driven by the engine 16 to generate electric power. The electric power generated by the generator 28 is transmitted to a demand destination in the floating facility 100 via a transmission line.

The floating facility 100 shown in FIGS. 2B to 5B is also provided with a first heat exchanger 8 for vaporizing liquefied natural gas (LNG) from the LNG tank 6 to obtain regasified LNG. .

The floating facility 100 shown in FIGS. 2B-5B includes a first LNG line 10 for conducting LNG from the LNG tank 6 to the first heat exchanger 8 and expanding the regasified LNG from the first heat exchanger 8. and a second LNG line 12 leading to the turbine. The first LNG line 10 is provided with an LNG pump 72 for boosting liquid LNG. The floating facility 100 also has a cooling water line 74 through which cooling water for cooling the engine 16 flows. It is designed to be guided to a heat exchanger 8 .

The first heat exchanger 8 heats and vaporizes the liquid LNG led from the first LNG line 10 by heat exchange with cooling water (heat medium) flowing through the cooling water line 74 to generate regasified LNG. is configured to The regasified LNG produced in the first heat exchanger 8 is supplied to the expansion turbine 18 (turbine 40) via the second LNG line, and the expansion turbine 18 is driven by the regasified LNG so supplied. At the same time, the generator 54 connected to the expansion turbine 18 is driven.

The regasified LNG discharged from the expansion turbine 18 (turbine 40) is guided to the gas facility (demand) via the regasified LNG supply line 14.

In the above-described embodiment, in the floating unit (FSRU) 100 capable of storing and regasifying the liquefied natural gas stored in the LNG tank 6, the cold heat of the LNG stored in the LNG tank 6 provided on the hull 2 can be used to drive the expansion turbine 18 . Therefore, by driving the power generator 54 with the expansion turbine 18, it becomes possible to generate power using the cold heat of LNG, and the energy efficiency of the floating facility 100 as a whole can be improved.

Also, the expansion turbine 18 in the above-described embodiment can be used as the turbine 40 as the main engine 4 for generating the propulsive force of the hull 2 . Accordingly, an LNG tanker 101 (see FIGS. 2A-5A) having a turbine 40 that can be used as the main engine 4 can be retrofitted and operated as a floating unit (FSRU) 100. FIG. Therefore, for example, it is possible to switch between the operation as the LNG tanker 101 and the operation as the floating facility (FSRU) 100 according to the demand for LNG, etc., thereby efficiently using the floating facility 100. can.

Further, in the above-described embodiment, the LNG tanker 101 having the engine 16 (internal combustion engine) that can be used as the main engine 4 can be modified and operated as the floating unit (FSRU) 100 . Therefore, it is possible to switch between the operation as the LNG tanker 101 and the operation as the FSRU, for example, according to the demand for LNG, and thereby the floating facility 100 can be used efficiently.

Further, in the above-described embodiment, the heat medium that exchanges heat with LNG in the first heat exchanger 8 includes cooling water after cooling the engine 16 . In this way, the cooling water of the engine 16 is used as a heat medium to regasify the LNG from the LNG tank 6, so that the exhaust heat of the engine 16 is effectively used to efficiently generate power. becomes possible.

2B, 3B and 3C, of the high pressure turbine 42, the intermediate pressure turbine 44 and the low pressure turbine 46 that make up the turbine 40, the intermediate pressure turbine 44 has the function of the expansion turbine 18.

That is, the regasified LNG from the first heat exchanger 8 is directly introduced into the intermediate pressure turbine 44 (expansion turbine 18) via the second LNG line 12 (introduction line) without passing through the high pressure turbine 42. It has become so. Further, the regasified LNG discharged from the intermediate pressure turbine 44 (expansion turbine 18) is discharged to the regasified LNG supply line 14 (discharge line) without passing through the low pressure turbine 46. . 2B and 3B, illustration of the low-pressure turbine 46 is omitted.

The volumetric flow rate of the fluid supplied to the turbine 40 varies when the turbine 40 is used as the main engine 4 during operation as the LNG tanker 101, and when the turbine 40 is used as the expansion turbine 18 for power generation during operation as the floating unit (FSRU) 100. It may differ depending on when it is used.
In this regard, the expansion turbine 18 according to the above-described embodiment is an intermediate pressure turbine 44 configured to be supplied with fluid having a lower pressure than the fluid supplied to the high pressure turbine 42 . That is, in the above-described embodiment, in the floating unit (FSRU) 100, the regasified LNG is introduced from the intermediate stage of the turbine 40, so the volume flow zone in the expansion turbine 18 is used as the LNG tanker 101. Easy to match with time. Therefore, in the floating facility 100, the expansion turbine 18 can be appropriately driven.

Further, the expansion turbine 18 according to the above-described embodiment is an intermediate pressure turbine 44 configured to be supplied with fluid having a higher pressure than the fluid supplied to the low pressure turbine 46 . That is, in the above-described embodiment, in the floating unit (FSRU) 100, since the regasified LNG is discharged from the middle stage of the turbine 40, the volumetric flow zone in the expansion turbine 18 is operated as the LNG tanker 101. Easy to match with time. Therefore, in the floating facility 100, the expansion turbine 18 can be appropriately driven.

In addition, by using only the intermediate stage of the turbine 40 (the intermediate pressure turbine 44 in the above-described embodiment) as the expansion turbine 18 driven by the regasified LNG, the other part of the turbine 40 can be used can also generate electricity.

For example, in the exemplary embodiment shown in FIG. 3C, steam from boiler 32 is supplied via steam supply line 76 to low pressure turbine 46, which has a separate rotating shaft from high pressure turbine 42 and intermediate pressure turbine 44. , a low pressure turbine 46 and a generator 55 connected to the low pressure turbine 46 . In this way, during operation as an FSRU, power can be generated not only by the expansion turbine 18 but also by the low-pressure turbine 46 driven by steam, making it possible to supply more power.

In the exemplary embodiment shown in FIGS. 4B and 5B, high pressure turbine 42 and intermediate pressure turbine 44 serve the function of expansion turbine 18 . That is, the expansion turbine 18 includes a high pressure turbine 42 (first turbine) and an intermediate pressure turbine (second turbine) whose inlet pressure is lower than that of the high pressure turbine 42 . The regasified LNG from the first heat exchanger 8 is supplied to the high pressure turbine 42 (first turbine). In addition, the regasified LNG discharged from the high-pressure turbine 42 (first turbine) is guided to the second heat exchanger 69 via the reheat line 78, and is mixed with the heat medium in the second heat exchanger 69. After being heated by heat exchange, it is supplied to the inlet of the intermediate pressure turbine 44 .

In the second heat exchanger 69 shown in FIGS. 4B and 5B, cooling water from the cooling water line 74 (cooling water after cooling the engine 16) is supplied as a heat medium for reheating the regasified LNG. It is meant to be guided. The first heat exchanger 8 and the second heat exchanger 69 may share a single casing as shown in FIGS. 4B and 5B, or may have separate casings. may have.

In the above-described embodiment, the expansion turbine 18 is fed with the high pressure turbine 42 (first turbine) and the fluid heated in the second heat exchanger 69 after being discharged from the high pressure turbine 42 (first turbine). and a pressure turbine 44 (second turbine). Therefore, as in the LNG tanker 101 shown in FIGS. 4A and 5A, when a reheat turbine (turbine 40) is used as the main engine 4, the reheat turbine can be used as a floating unit (FSRU) with the structure as it is. It can be used as an expansion turbine 18 when operating as 100 . Therefore, it is possible to efficiently generate power using the cold energy of LNG while suppressing equipment costs.

2B to 5B by modifying the LNG tanker 101 shown in FIGS. 2A to 5A to obtain the floating facility 100 shown in FIGS. and providing a regasified LNG supply line 14 for guiding the regasified LNG produced in the first heat exchanger 8 to the gas facility (demand destination). include. The first heat exchanger 8 is provided to satisfy the following condition (A) in relation to the expansion turbine 18 so that the turbine 40 constituting the main engine 4 functions as the expansion turbine 18 .
(A) Expansion turbine 18 is configured to be driven by regasified LNG from first heat exchanger 8 .

In addition, the method for retrofitting an LNG tanker further includes the step of providing a first LNG line 10 for guiding LNG from the LNG tank 6 to the first heat exchanger 8; to an expansion turbine.

The LNG tanker modification method may further include the step of providing a cooling water line for guiding the cooling water used to cool the engine 16 to the first heat exchanger 8 .

Further, when obtaining the floating facility 100 shown in FIGS. 3B and 5B from the LNG tanker 101 shown in FIGS. 3A and 5A, the gear 58A and the propeller 5A connected to the turbine 40 are separated from the turbine 40, and the turbine Connecting a generator 54 to 40 may be included.

When obtaining the floating facility 100 shown in FIGS. 4B and 5B from the LNG tanker 101 shown in FIGS. 4A and 5A, the step of providing the second heat exchanger 69 and the high-pressure turbine 42 (first turbine) This may include providing a reheat line 78 extending from the outlet through the second heat exchanger 69 to the inlet of the intermediate pressure turbine 44 (the second turbine).

By modifying the LNG tanker 101 by the modification method described above, for example, the floating facility 100 according to the embodiment shown in FIGS. 2B to 5B can be obtained. The floating facility 100 obtained in this manner enables power generation using the cold heat of LNG, and the energy efficiency of the floating facility as a whole can be improved.

FIG. 6 is a schematic diagram of an expansion turbine 18 (eg, the expansion turbine 18 shown in FIGS. 2B-5B) according to some embodiments. The expansion turbine 18 shown in FIG. 6 includes a rotor 19, a casing 18a surrounding the rotor 19, and fluid (18 in the case of the expansion turbines of FIGS. and a seal 80 for suppressing leakage of liquefied LNG).

The seal portion 80 includes a plurality of labyrinth portions 82A-82C spaced apart in the axial direction. At a position between the adjacent labyrinth portions 82B and 82C, an inert gas is supplied to the space 83A formed between the rotor 19 and the casing 18a via the inert gas supply line 84 and the branch lines 84a and 84b. A gas (eg nitrogen) is supplied. The pressure of the inert gas supplied to the space 83A described above is higher than the fluid supplied to the expansion turbine 18 (in the case of the expansion turbines of FIGS. 2B-5B, 18 is regasified LNG).

The inert gas supply line 84 is provided with a valve 85 for adjusting the flow rate of the inert gas. In addition, the fluid leaked from between the rotor 19 and the casing 18a through the labyrinth portion 82A (in the case of the expansion turbines in FIGS. 2B to 5B, 18 is regasified LNG), and the fluid leaked from the space 83A through the labyrinth portion 82B. The inert gas is recovered through a recovery line 86 and a space 83B formed between the rotor 19 and the casing 18a at a position between the adjacent labyrinth portions 82A and 82B.

That is, the seal portion 80 is supplied with inert gas (eg, nitrogen) at a higher pressure than the fluid supplied to the expansion turbine 18 (18 in the case of the expansion turbines of FIGS. 2B to 5B is regasified LNG). It has become.

According to the above-described configuration, an inert gas (for example, nitrogen gas) having a higher pressure than the fluid (regasified LNG or heat medium) supplied to the expansion turbine 18 is supplied to the seal portion 80. Therefore, for example, Even if the operation mode is changed between the floating facility 100 and the LNG tanker 101 and the type of fluid supplied to the expansion turbine 18 is changed, appropriate shaft sealing can be achieved without changing the structure of the seal portion 80. Become.

FIGS. 7A, 8A, 9A, 10A and 11A (hereinafter also referred to as FIGS. 7A to 11A) show the LNG tanker before modification to the floating facility 100 according to one embodiment. 101 is a schematic configuration diagram showing 101. FIG.
FIGS. 7B, 8B, 9B, 10B and 11B (hereinafter also referred to as FIGS. 7B to 11B) show the modified LNG tanker 101 shown in FIGS. 7A to 10A. It is a schematic block diagram which shows the floating facility 100 obtained.

The LNG tanker 101 shown in FIGS. 7A to 11A is equipped with an engine 16 (internal combustion engine) as the main engine 4 .
LNG from the LNG tank 6 is supplied to the engine 16 via an LNG fuel supply line 88 . The LNG fuel supply line 88 is provided with a pump 90 for boosting the LNG to an appropriate pressure and a valve 89 for adjusting the flow rate of the LNG supplied to the engine 16 . The engine 16 is configured to rotationally drive the propeller 5 (propulsion device). The rotational energy generated by the engine 16 may be transmitted to the propeller 5 via a gear (not shown), or may be generated by driving a generator (not shown) by the engine 16. The electric motor may be driven by the electric power supplied to the electric motor, and the propeller 5 may be driven by the electric motor.

In the exemplary embodiment shown in Figures 7A and 8A, a LNG tanker 101 is provided with a thermodynamic cycle 102 including a circuit 104 through which a working fluid heat carrier flows. This thermodynamic cycle 102 includes an expansion turbine 18 provided on circuit 104, a condenser 106 provided downstream of expansion turbine 18, a pump 108 provided downstream of condenser 106, and pump 108 and an evaporator 110 provided downstream of the Rankine cycle. A generator 113 is connected to the expansion turbine 18 .

The expansion turbine 18 is configured to expand the heat medium flowing through the circuit 104 of the thermodynamic cycle 102 to drive the generator 113 to produce electrical power.

The condenser 106 is configured to condense the heat medium from the expansion turbine 18 by heat exchange with a low temperature heat source. Seawater, for example, can be used as a low-temperature heat source.
The pump 108 is configured to raise the pressure of the heat medium that has been condensed and liquefied by the condenser 106 .

The evaporator 110 is configured to evaporate the liquid heat medium pressurized by the pump 108 by heat exchange with a high-temperature heat source. Exhaust gas from the engine 16, for example, can be used as the high-temperature heat source. 7A and 8A, exhaust gas from the engine 16 is supplied to the evaporator 110 via an exhaust gas line 92. As shown in FIG.

In the thermodynamic cycle 102 configured in this way, the exhaust heat of the engine 16 recovered by heat exchange in the evaporator 110 can be used to drive the generator 113 .

In the floating facility 100 shown in FIGS. 7B and 8B, the condenser 106 constituting the thermodynamic cycle 102 that was operated during operation as the LNG tanker 101 (before modification; see FIGS. 7A to 8A) is operated as the first heat. It is used as an exchanger 8.

The floating facility 100 shown in FIGS. 7B and 8B is provided with a first LNG line 10 for guiding the LNG from the LNG tank 6 to the first heat exchanger 8, and the first LNG line 10 for boosting the liquid LNG. and a valve 71 for regulating the flow of LNG in the first LNG line 10 . Also, the regasified LNG produced in the first heat exchanger 8 is guided to the gas facility (demand destination) via the regasified LNG supply line 14 .

LNG from the LNG tank 6 is supplied via the first LNG line 10 to the condenser 106 (first heat exchanger 8) that constitutes the thermodynamic cycle 102 as a low-temperature heat source for the thermodynamic cycle 102. ing. That is, the condenser 106 is configured to condense the heat medium of the thermodynamic cycle 102 by heat exchange with LNG. The expansion turbine 18 is configured to be driven by the heat medium that has passed through the condenser 106 (the first heat exchanger 8), the pump, and the evaporator 110 and is in a gaseous state.

According to the above-described embodiment, in the floating facility 100, the expansion turbine 18 on the thermodynamic cycle 102 can be driven using LNG from the LNG tank 6 provided on the ship 2 as a low-temperature heat source. That is, the expansion turbine 18 is supplied with the heat medium, which is the working fluid of the thermodynamic cycle 102 , rather than the LNG-derived gas from the LNG tank 6 . Therefore, while avoiding leakage of LNG from the expansion turbine 18, it is possible to generate power using cold heat of LNG.

Further, according to the above-described embodiment, unlike the case where the regasification LNG is expanded by the direct expansion turbine, the pressure of the heat medium in the thermodynamic cycle 102 is changed to the gas supply pressure of the regasification LNG (supply to the demand destination Since it can be set regardless of the pressure), it can be applied to a wide range of LNG supply pressures, such as high pressures such as 10 to 15 MPa.
Note that when the regasified LNG is expanded by a direct expansion turbine (see, for example, FIGS. 2B to 5B), when the regasified LNG feed pressure is set high, the inlet pressure of the expansion turbine 18 is also increased accordingly. It may be difficult to achieve the required insufflation pressure because of the need.

Further, in the floating facility 100 according to the above-described embodiment, the evaporator 110 that constitutes the thermodynamic cycle 102 is the LNG-derived fuel gas stored in the LNG tank 6 (supplied via the LNG fuel supply line 88 The exhaust heat of the engine 16 to which the gas is supplied is used to evaporate the heat medium.

In this way, since the exhaust heat of the engine 16 is used as a high-temperature heat source for evaporating the heat medium (working fluid) in the thermodynamic cycle 102, the exhaust heat of the engine 16 is effectively used to efficiently generate power. It is possible to do

It should be noted that while the exemplary embodiment shown in FIGS. 7B and 8B uses exhaust gas from the engine 16 as the high temperature heat source described above, in other embodiments, the high temperature heat source may be cooling water after the engine 16 has been cooled. may be
In another embodiment, the high-temperature heat source may be seawater or the like.

In the exemplary embodiment shown in FIG. 8A, the LNG tanker 101 (floating facility 100) is supplied with LNG-derived fuel gas (gas supplied via the LNG fuel supply line 88) stored in the LNG tank 6. It has an engine 16 that is Engine 16 is configured to be supplied with regasified LNG from first heat exchanger 8 (ie, condenser 106) as fuel.

In the above-described embodiment, the LNG regasified by heat exchange with the heat medium in the first heat exchanger 8 as the condenser 106 in the thermodynamic cycle 102 is supplied to the engine 16 as fuel. The LNG tanker 101 (floating facility 100) can be efficiently operated.

In the exemplary embodiment shown in FIGS. 9A and 10A, the LNG tanker 101 includes a compressor 94 for compressing air supplied to the engine 16 and a compressor 94 configured to be driven by the exhaust gas from the engine 16. A supercharger 93 is provided including a turbine 96 and a rotating shaft 95 connecting the compressor 94 and the turbine 96 . A generator 113 is connected to the turbine 96 .

Air is supplied to the compressor 94 via an air introduction line 114 . Compressed air produced by compressor 94 is supplied to engine 16 via engine inlet line 116 . Exhaust gases produced by combustion of fuel in engine 16 exit engine 16 via engine outlet line 118 and are channeled to turbine 96 . Turbine 96 is driven by exhaust gases from engine 16, which in turn drives generator 113 to produce electrical power. Exhaust gases having completed work in turbine 96 are discharged through exhaust gas line 120 .

9A and 10A, the LNG fuel supply line 88 for supplying LNG from the LNG tank 6 to the engine 16 is provided with a heat exchanger 98 (described later) for regasifying the LNG. second cooler) is provided.
In the exemplary embodiment shown in FIG. 9A, heat exchanger 98 (second cooler) is configured to heat and vaporize the LNG by exchanging heat with seawater introduced via line 99 .
In the exemplary embodiment shown in FIG. 10A, heat exchanger 98 (secondary cooler) is configured to heat and vaporize the LNG by exchanging heat with air introduced via line 99 . Further, in the exemplary embodiment shown in FIG. 10A, air after passing through the heat exchanger 98 (second cooler) is supplied to the compressor 94 via an air introduction line 114. .

In the floating facility 100 shown in FIGS. 9B and 10B, heat including the compressor 94 and turbine 96 of the supercharger 93 used during operation as the LNG tanker 101 (before modification; see FIGS. 9A to 10A) A dynamic cycle 122 is formed. This thermodynamic cycle 122 is a Brayton cycle without a phase change of the heat medium (working fluid).

In the thermodynamic cycle 122, the circuit 124 through which the heat transfer medium flows is provided with the turbine 96 described above. This turbine 96 functions as the expansion turbine 18 . A first cooler 126 for cooling the heat medium is provided downstream of the turbine 96 (expansion turbine 18) on the thermodynamic cycle 122 . The first cooler 126 includes a first heat exchanger 8 configured to cool the heat transfer medium by exchanging heat with liquefied natural gas.

Further, on the thermodynamic cycle 122, a compressor 94 (compressor 94 described above) is provided downstream of the first cooler 126 for compressing the heat medium. As mentioned above, the compressor 94 and turbine 96 are connected via the rotating shaft 95 . A generator 113 is connected to the turbine 96 (expansion turbine 18). A heater 128 is provided downstream of the compressor 94 on the thermodynamic cycle 122 . Exhaust gas from the engine 16 is supplied to the heater 128 via an exhaust gas line 130 . The heater 128 is configured to heat the heat medium through heat exchange with exhaust gas from the engine 16 .

Also, in the exemplary embodiment shown in FIG. 10, in the thermodynamic cycle 122, downstream of the turbine 96 (expansion turbine 18) and upstream of the first cooler 126 is a heat exchanger 98 (second cooler). is provided.

The floating facility 100 shown in FIGS. 9B and 10B is provided with a first LNG line 10 for guiding LNG from the LNG tank 6 to the first heat exchanger 8, and the first LNG line 10, and is provided in the first LNG line 10 to pressurize the liquid LNG. and a valve 71 for regulating the flow of LNG in the first LNG line 10 . Also, the regasified LNG produced in the first heat exchanger 8 is guided to the gas facility (demand destination) via the regasified LNG supply line 14 .

The first cooler 126 (first heat exchanger 8) constituting the thermodynamic cycle 122 is supplied with LNG from the LNG tank 6 via the first LNG line 10 as a low-temperature heat source of the thermodynamic cycle 122. It has become. That is, the first cooler 126 is configured to cool the heat medium of the thermodynamic cycle 122 by heat exchange with LNG. The turbine 96 (expansion turbine 18 ) is configured to be driven by the gaseous heat medium after passing through the first cooler 126 .

According to the above embodiment, in the floating facility 100, the turbine 96 (expansion turbine) on the thermodynamic cycle 122 can be driven using the LNG from the LNG tank 6 provided on the hull 2 as a low-temperature heat source. . That is, the expansion turbine 18 is supplied with the heat medium, which is the working fluid of the thermodynamic cycle 122 , rather than the LNG-derived gas from the LNG tank 6 . Therefore, while avoiding leakage of LNG from the expansion turbine 18, it is possible to generate power using cold heat of LNG.
Further, in the case of the LNG tanker 101 equipped with the turbine 96 or the compressor 94, the above-mentioned A configuration according to an embodiment can be obtained. Therefore, it is possible to efficiently generate power using the cold energy of LNG while suppressing equipment costs.

Further, in the above-described embodiment, the floating facility 100 includes the rotating shaft 95 that connects the turbine 96 (expansion turbine 18) and the compressor 94, and the compressor 94 is connected to the turbine via the rotating shaft 95. 96 (expansion turbine 18).

Thus, the compressor 94 and the turbine 96 (expansion turbine 18 ) on the thermodynamic cycle 122 are connected via the rotating shaft 95 . Thus, if the LNG tanker 101 uses equipment including a compressor 94 and a turbine 96 connected by a rotating shaft 95 (supercharger 93 described above), this equipment is used to form the thermodynamic cycle 122. By doing so, the floating facility 100 according to the above-described embodiment can be obtained. Therefore, it is possible to efficiently generate power using the cold heat of LNG while suppressing equipment costs.

Further, in the floating facility 100 according to the above-described embodiment, the heater 128 that constitutes the thermodynamic cycle 122 is the LNG-derived fuel gas stored in the LNG tank 6 (supplied via the LNG fuel supply line 88 The exhaust heat of the engine 16 to which the gas is supplied is used to evaporate the heat medium.

In this way, since the exhaust heat of the engine 16 is used as a high-temperature heat source for heating the heat medium (working fluid) in the thermodynamic cycle 122, the exhaust heat of the engine 16 is effectively used to efficiently generate power. It is possible to do

9B and 10B, the exhaust gas of the engine 16 is used as the above-described high-temperature heat source, but in other embodiments, the high-temperature heat source is the cooling water after cooling the engine 16. may be
In another embodiment, the high-temperature heat source may be seawater or the like.

Also, in the exemplary embodiment shown in FIG. 10B, a heat exchanger provided between turbine 96 (expansion turbine 18) and first cooler 126 (first heat exchanger 8) on thermodynamic cycle 122 98 (second cooler) is configured to cool the heat medium by heat exchange with the LNG supplied to the engine 16 .

In this way, the heat medium of the thermodynamic cycle 122 is further cooled by heat exchange with LNG from the LNG tank 6 in the heat exchanger 98 (second cooler). , can generate electricity more efficiently.

In the exemplary embodiment shown in FIG. 11A, the LNG fuel supply line 88 is provided with a heat exchanger 98 as the first heat exchanger 8 for heating and vaporizing the LNG. Heat exchanger 98 may be configured to heat the LNG, for example, by exchanging heat with seawater.

In the exemplary embodiment shown in FIG. 11B, an expansion turbine 136 (18) is provided in the branch line 132 branching off from the LNG fuel supply line 88. As shown in FIG. Branch line 132 is provided with valve 134 for regulating the flow of regasified LNG supplied to expansion turbine 136 . A generator 138 is connected to the expansion turbine 136 . The expansion turbine 136 is supplied with the regasified LNG through the branch line 132 , and the expansion turbine 136 expands the regasified LNG and drives the generator 138 . In this manner, electrical power is generated at generator 138 . The regasified LNG discharged from the expansion turbine 136 is temperature-controlled in the heat exchanger 140 and then guided to the gas facility (demand destination) via the regasified LNG supply line 14 .

Also, in the exemplary embodiment shown in FIG. 11B, the heat exchanger 98 provided in the LNG fuel supply line 88 forms part of the thermodynamic cycle 102 . In the embodiment shown in FIG. 11B, the thermodynamic cycle 102 includes a circuit 104 through which a heat medium, which is a working fluid, flows, an expansion turbine 112 (18) provided on the circuit 104, and a downstream side of the expansion turbine 112. The Rankine cycle includes a condenser 106 , a pump 108 provided downstream of the condenser 106 , and an evaporator 110 provided downstream of the pump 108 . A generator 113 is connected to the expansion turbine 18 .

The expansion turbine 18 is configured to expand the heat medium flowing through the circuit 104 of the thermodynamic cycle 102 to drive the generator 113 to produce electrical power.

Condenser 106 (first heat exchanger 8) constituting thermodynamic cycle 102 is supplied with LNG from LNG tank 6 via LNG fuel supply line 88 as a low-temperature heat source of thermodynamic cycle 102. It's becoming That is, the condenser 106 is configured to condense the heat medium of the thermodynamic cycle 102 by heat exchange with LNG. The expansion turbine 112 is configured to be driven by the heat medium that has passed through the condenser 106 (first heat exchanger 8), the pump 108, and the evaporator 110 and is in a gaseous state.

The evaporator 110 is configured to evaporate the liquid heat medium pressurized by the pump 108 by heat exchange with a high-temperature heat source. A high temperature heat source is directed through line 107 to evaporator 110 . Exhaust gas from the engine 16 or cooling water for the engine 16 can be used as the high-temperature heat source, for example. Moreover, you may use seawater as a high temperature heat source.

In the thermodynamic cycle 102 configured in this way, the exhaust heat of the engine 16 recovered by heat exchange in the evaporator 110 can be used to drive the generator 113 .

In the embodiment described above, the expansion turbine 136 driven by the regasified LNG from the first heat exchanger 8 (heat exchanger 98) forms part of the thermodynamic cycle 102 utilizing the LNG as a low temperature heat source. , with an expansion turbine 112 driven by a gaseous heat medium. This can increase the power recovered from the LNG cold.

2B to 5B by modifying the LNG tanker 101 shown in FIGS. 6A to 11A to obtain the floating facility 100 shown in FIGS. and providing a regasified LNG supply line 14 for guiding the regasified LNG produced in the first heat exchanger 8 to the gas facility (demand destination). include. The first heat exchanger 8 is provided to satisfy the following condition (B) in relation to the expansion turbine 18 so that the turbine 40 constituting the main engine 4 functions as the expansion turbine 18 .
(B) The expansion turbine 18 forms part of a thermodynamic cycle 102, 122 that utilizes liquefied natural gas as a low temperature heat source in the first heat exchanger 8 and is configured to be driven by a gaseous heat medium. be done.

In addition, the method for retrofitting an LNG tanker further includes the step of providing a first LNG line 10 for guiding LNG from the LNG tank 6 to the first heat exchanger 8; to an expansion turbine.

The LNG tanker modification method may further include the step of providing a cooling water line for guiding the cooling water used to cool the engine 16 to the first heat exchanger 8 .

By modifying the LNG tanker 101 by the modification method described above, for example, the floating facility 100 according to the embodiment shown in FIGS. 6B to 11B can be obtained. The floating facility 100 obtained in this manner enables power generation using the cold heat of LNG, and the energy efficiency of the floating facility as a whole can be improved.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and includes modifications of the above-described embodiments and modes in which these modes are combined as appropriate.

As used herein, expressions such as "in a certain direction", "along a certain direction", "parallel", "perpendicular", "central", "concentric" or "coaxial", etc. express relative or absolute arrangements. represents not only such arrangement strictly, but also the state of being relatively displaced with a tolerance or an angle or distance to the extent that the same function can be obtained.
For example, expressions such as "identical", "equal", and "homogeneous", which express that things are in the same state, not only express the state of being strictly equal, but also have tolerances or differences to the extent that the same function can be obtained. It shall also represent the existing state.
Further, in this specification, expressions representing shapes such as a quadrilateral shape and a cylindrical shape not only represent shapes such as a quadrilateral shape and a cylindrical shape in a geometrically strict sense, but also within the range in which the same effect can be obtained. , a shape including an uneven portion, a chamfered portion, and the like.
Moreover, in this specification, the expressions “comprising”, “including”, or “having” one component are not exclusive expressions excluding the presence of other components.

2 Hull 2a Bow 2b Stern 3 Rudder 4 Main engine 5 Propeller 5A Port side propeller 5B Starboard side propeller 6 LNG tank 8 First heat exchanger 10 First LNG line 12 Second LNG line 14 Regasification LNG supply line 16 Engine 18 Expansion turbine 18a Casing 19 Rotor 20 Gas supply line 20a First branch line 20b Second branch line 22 Compressor 24 Gas header 26 Oil supply line 28 Generator 30 Valve 32 Boiler 34 Reheater 36 Oil supply line 38 Steam supply line 40 Turbine 42 High pressure turbine 44 intermediate pressure turbine 46 low pressure turbine 48 reverse turbine 50 reheater inlet line 52 reheater outlet line 54 generator 55 generator 56 transmission lines 58A, 58B gear 62 transformer 64 converter 66 electric motor 69 second heat exchanger 71 Valve 72 LNG pump 74 Cooling water line 76 Steam supply line 78 Reheat line 80 Seal parts 82A, 82B, 82C Labyrinth parts 83A, 83B Space 84 Inert gas supply lines 84a, 84b Branch line 85 Valve 86 Recovery line 88 LNG fuel supply Line 89 Valve 90 Pump 92 Exhaust gas line 93 Supercharger 94 Compressor 95 Rotating shaft 96 Turbine 98 Heat exchanger 99 Line 100 Floating installation 101 LNG tanker 102 Thermodynamic cycle 104 Circuit 106 Condenser 107 Line 108 Pump 110 Evaporator 112 Expansion turbine 113 Generator 114 Air intake line 116 Engine inlet line 118 Engine outlet line 120 Exhaust gas line 122 Thermodynamic cycle 124 Circuit 126 First cooler 128 Heater 130 Exhaust gas line 132 Branch line 134 Valve 136 Expansion turbine 138 Generator 140 Heat Exchanger

Claims (11)

a floating body;
an LNG tank provided on the floating body;
a first heat exchanger for vaporizing the liquefied natural gas from the LNG tank by heat exchange with a heat medium to obtain regasified LNG;
(A) an expansion turbine configured to be driven by said regasified LNG from said first heat exchanger ;
a high-pressure turbine having an outlet portion that can communicate with an inlet side of the expansion turbine and including turbine blades that are shorter than the expansion turbine;
an introduction line configured to introduce the regasified LNG directly into the expansion turbine without passing through the high pressure turbine;
Floating facility with The floating facility according to claim 1, further comprising an internal combustion engine configured to be able to supply liquefied natural gas from said LNG tank. The floating facility according to claim 2, wherein the heat medium contains cooling water after cooling the internal combustion engine. a floating body;
an LNG tank provided on the floating body;
a first heat exchanger for vaporizing the liquefied natural gas from the LNG tank by heat exchange with a heat medium to obtain regasified LNG;
(A) an expansion turbine configured to be driven by said regasified LNG from said first heat exchanger;
a low-pressure turbine having an inlet portion communicable with the outlet side of the expansion turbine and including turbine blades longer than the expansion turbine;
a discharge line configured to discharge the regasified LNG from the expansion turbine without passing through the low pressure turbine.
Floating equipment. a floating body;
an LNG tank provided on the floating body;
a first heat exchanger for vaporizing the liquefied natural gas from the LNG tank by heat exchange with a heat medium to obtain regasified LNG;
(A) an expansion turbine configured to be driven by said regasified LNG from said first heat exchanger;
with
the expansion turbine includes a first turbine and a second turbine having a lower inlet pressure than the first turbine;
said first turbine is configured to be supplied with said regasified LNG from said first heat exchanger;
further comprising a second heat exchanger for heating the regasified LNG discharged from the first turbine;
the second turbine configured to be supplied with the regasified LNG from the second heat exchanger
Floating equipment. a floating body;
an LNG tank provided on the floating body;
a first heat exchanger for vaporizing the liquefied natural gas from the LNG tank by heat exchange with a heat medium to obtain regasified LNG;
(B) the first heat exchanger forms part of a thermodynamic cycle utilizing the liquefied natural gas as a low-temperature heat source and is configured to be driven by the gaseous heat medium; an expansion turbine that satisfies
a first cooler provided downstream of the expansion turbine on the thermodynamic cycle for cooling the heat medium;
a compressor provided downstream of the first cooler on the thermodynamic cycle for compressing the heat medium;
a heater provided downstream of the compressor on the thermodynamic cycle for heating the heat medium;
The first cooler includes the first heat exchanger configured to cool the heat medium by heat exchange with the liquefied natural gas,
An internal combustion engine configured to be able to supply fuel gas derived from the liquefied natural gas stored in the LNG tank,
The heater is configured to heat the heat medium using exhaust heat of the internal combustion engine.
Floating equipment. further comprising a rotating shaft connecting the expansion turbine and the compressor;
7. The floating facility according to claim 6 , wherein said compressor is configured to be driven by said expansion turbine via said rotating shaft. a floating body;
an LNG tank provided on the floating body;
a first heat exchanger for vaporizing the liquefied natural gas from the LNG tank by heat exchange with a heat medium to obtain regasified LNG;
(B) the first heat exchanger forms part of a thermodynamic cycle utilizing the liquefied natural gas as a low-temperature heat source and is configured to be driven by the gaseous heat medium; an expansion turbine that satisfies
a first cooler provided downstream of the expansion turbine on the thermodynamic cycle for cooling the heat medium;
a compressor provided downstream of the first cooler on the thermodynamic cycle for compressing the heat medium;
a heater provided downstream of the compressor on the thermodynamic cycle for heating the heat medium;
The first cooler includes the first heat exchanger configured to cool the heat medium by heat exchange with the liquefied natural gas,
an internal combustion engine configured to be able to supply fuel gas derived from the liquefied natural gas stored in the LNG tank;
a second cooler provided between the expansion turbine and the first cooler on the thermodynamic cycle;
The second cooler is configured to cool the heat medium by heat exchange with liquefied natural gas supplied from the LNG tank to the internal combustion engine.
Floating equipment. The expansion turbine includes a rotor, a casing that surrounds the rotor, and a seal that suppresses fluid leakage through a gap between the rotor and the casing,
9. The sealing portion according to any one of claims 1 to 8 , wherein the seal portion is configured to be supplied with an inert gas having a higher pressure than the regasified LNG or the heat medium supplied to the expansion turbine. Floating equipment. 10. A floating facility according to any preceding claim, further comprising a generator configured to be driven by said expansion turbine. a hull;
a main engine provided in the hull;
A method for obtaining a floating facility by modifying an LNG ship comprising an LNG tank provided on the hull,
The floating facility is
a floating body;
an LNG tank provided on the floating body;
a first heat exchanger for vaporizing the liquefied natural gas from the LNG tank by heat exchange with a heat medium to obtain regasified LNG;
configured to be driven by the regasified LNG from the first heat exchanger, or
configured to be driven by the heat medium in the gaseous state forming part of a thermodynamic cycle utilizing the liquefied natural gas as a low temperature heat source in the first heat exchanger;
an expansion turbine satisfying the conditions of
including
providing a first heat exchanger for heat exchange vaporizing liquefied natural gas from said LNG tank to obtain regasified LNG;
forming a regasified LNG supply line that directs the regasified LNG to a gas facility;
with
The first heat exchanger is configured in relation to the main engine or a turbine forming part of the thermodynamic cycle for waste heat recovery of the main engine so that the expansion turbine functions as an expansion turbine. A method for manufacturing a floating facility that satisfies the conditions of (A) or (B).
(A) the expansion turbine is configured to be driven by the regasified LNG from the first heat exchanger;
(B) The first heat exchanger forms a part of a thermodynamic cycle in which the liquefied natural gas is used as a low-temperature heat source, and the expansion turbine is driven by the gaseous heat medium. .

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