CN113557196B

CN113557196B - Floating type device and method for manufacturing floating type device

Info

Publication number: CN113557196B
Application number: CN202080019990.7A
Authority: CN
Inventors: 高田亮; 斋藤英司
Original assignee: Mitsubishi Heavy Industries Marine Machinery and Equipment Co Ltd
Current assignee: Mitsubishi Heavy Industries Marine Machinery and Equipment Co Ltd
Priority date: 2019-03-15
Filing date: 2020-03-13
Publication date: 2024-02-13
Anticipated expiration: 2040-03-13
Also published as: CN113557196A; JP2020147221A; JP7316068B2; KR20210124358A; KR102572399B1; WO2020189536A1

Abstract

The floating type device is provided with: the LNG storage system includes a floating body, an LNG tank provided on the floating body, a first heat exchanger for vaporizing liquefied natural gas from the LNG tank by heat exchange with a heat medium to obtain regasified LNG, and an expansion turbine satisfying the following condition (a) or (B). (A) The expansion turbine is configured to be driven by the regasified LNG from the first heat exchanger. (B) The expansion turbine is configured to form part of a thermodynamic cycle that uses the liquefied natural gas as a low-temperature heat source in the first heat exchanger and is driven by the heat medium in a gaseous state.

Description

Floating type device and method for manufacturing floating type device

Technical Field

The present invention relates to a floating body type device and a method for manufacturing the floating body type device.

Background

Liquefied Natural Gas (LNG) is typically stored in a state of a cryogenic liquid at about-160 ℃. Thus, a method for effectively utilizing the cold and hot energy of LNG is proposed.

For example, patent document 1 discloses a cold and hot power generation device that generates power by using cold and hot LNG. More specifically, the cold-hot power generation device described in patent document 1 includes a thermal cycle in which a heat medium cooled by heat exchange with LNG is used as a cold heat source, and exhaust gas discharged from a main combustion engine fuelled with LNG is used as a heat source. Then, the generator is driven by an expansion turbine provided in the thermal cycle to generate electric power.

Prior art literature

Patent literature

Patent document 1: japanese patent laid-open No. 2014-104847

Technical problem to be solved by the invention

However, a Floating body Storage regasification Facility (FSRU) in which LNG Storage tanks and regasification facilities are mounted on a Floating body functions as a Storage and regasification facility of LNG, like an LNG receiving base on land, and is fixedly moored to a trestle or the like for use. However, in the above-described cold and hot power generation using LNG, a large-scale apparatus is generally used, and therefore, in such a floating body type facility, the cold and hot power generation is not introduced because of problems such as restrictions on space on the floating body and installation costs of the apparatus. Accordingly, in the floating body type plant, it is required to introduce cold and hot power generation to improve energy conversion efficiency.

Disclosure of Invention

In view of the above, an object of at least one embodiment of the present invention is to provide a floating body type device and a method for manufacturing the floating body type device, which can improve energy conversion efficiency.

Technical means for solving the technical problems

(1) The floating body device according to at least one embodiment of the present invention includes:

a floating body;

an LNG tank provided on the floating body;

A first heat exchanger for vaporizing liquefied natural gas from the LNG tank by heat exchange with a heat medium to obtain regasified LNG; and

an expansion turbine is provided with a plurality of air-flow channels,

the expansion turbine satisfies the following conditions (a) or (B):

(A) The expansion turbine is configured to be driven by the regasified LNG from the first heat exchanger;

(B) The expansion turbine is configured to be driven by the heat medium in a gaseous state, and to form a part of a thermodynamic cycle using the liquefied natural gas as a low-temperature heat source in the first heat exchanger.

The term "regasified LNG" as used herein refers to a gas obtained by vaporizing Liquefied Natural Gas (LNG) by heating the LNG in a heat exchanger.

According to the configuration of (1) above, in the floating body Facility (FSRU) capable of storing and regasifying the liquefied natural gas stored in the LNG tank, the expansion turbine can be driven by the cold and hot heat of the LNG stored in the LNG tank provided on the floating body. Therefore, by driving the generator by the expansion turbine, power generation can be performed by using the cold and hot heat of LNG, and the energy conversion efficiency of the entire floating body plant can be improved.

The expansion turbine satisfying the condition (a) can be used as a turbine (for example, a steam turbine) as a main engine for generating the propulsion force of the float. In this case, an LNG tanker (carrier) having a turbine usable as a host can be operated as a floating LNG storage regasification Facility (FSRU). Therefore, for example, in connection with the need for LNG, the operation of the floating facility can be switched between the LNG tanker and the FSRU, and thus the floating facility can be effectively utilized.

(2) In several embodiments, in the structure of (1) above,

the floating body facility further includes an internal combustion engine configured to be able to be supplied with liquefied natural gas from the LNG tank.

According to the configuration of (2) above, an LNG tanker (carrier) having a turbine usable as a host can be operated as a floating LNG storage regasification Facility (FSRU). Therefore, for example, in connection with the need for LNG, the operation of the floating facility can be switched between the LNG tanker and the FSRU, and thus the floating facility can be effectively utilized.

In addition, according to the configuration of (2) above, when the floating body facility is used as an FSRU, power generation can be performed by the internal combustion engine in addition to power generation by the expansion turbine. Therefore, the amount of power generation can be flexibly adjusted in response to the power demand in the floating body plant.

(3) In several embodiments, in the structure of (2) above,

the expansion turbine satisfies the condition of (a),

the heat medium includes cooling water after cooling the internal combustion engine.

According to the configuration of (3), since LNG from the LNG tank is regasified using cooling water of the internal combustion engine as a heat medium, waste heat of the internal combustion engine can be effectively utilized to effectively generate electric power.

(4) In several embodiments, in any one of the structures (1) to (3) above,

the expansion turbine satisfies the condition of (a),

the floating body type device is provided with:

a high-pressure turbine having an outlet portion capable of communicating with an inlet side of the expansion turbine, and including turbine blades shorter than the expansion turbine; and

and 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 differs between the case where the turbine is used as a host or the like when the turbine is used as an LNG tanker and the case where the turbine is used as an expansion turbine for power generation when the turbine is used as an FSRU. In this regard, the expansion turbine (4) is a turbine configured to be supplied with a fluid at a lower pressure than the fluid supplied to the high-pressure turbine. That is, in the configuration of (4) above, in the floating body Facility (FSRU), since the regasified LNG flows in from a middle stage of the turbine, it is easy to match the volume flow rate band in the expansion turbine with that in operation as an LNG tanker. Therefore, in the floating body apparatus, the expansion turbine can be appropriately driven.

(5) In several embodiments, in any one of the structures (1) to (4) above,

The expansion turbine satisfies the condition of (a),

the floating body type device is provided with:

a low-pressure turbine having an inlet portion communicable with an outlet side of the expansion turbine and including turbine blades longer than the expansion turbine; and

and 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 a fluid at a higher pressure than the fluid supplied to the low-pressure turbine. That is, in the configuration of (5) above, in the floating body Facility (FSRU), the regasified LNG is discharged from the middle stage of the turbine, and therefore, the volume flow rate zone in the expansion turbine is easily matched with that in operation as an LNG tanker. Therefore, in the floating body apparatus, the expansion turbine can be appropriately driven.

(6) In several embodiments, in any one of the structures (1) to (5) above,

the expansion turbine satisfies the condition of (a),

the expansion turbine comprises a first turbine and a second turbine having a lower inlet pressure than the first turbine,

the first turbine is configured to be fed with the regasified LNG from the first heat exchanger,

The floating body plant is further provided with 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 of (6) above, the expansion turbine has a configuration of a reheat turbine including the first turbine and the fluid to be heated after being discharged from the first turbine is supplied. Therefore, for example, in the case where the reheat turbine is used as a main unit in an LNG tanker, the reheat turbine can be used as an expansion turbine when the reheat turbine is used as an FSRU in its original configuration. Therefore, the facility cost can be suppressed, and the power generation can be efficiently performed using the cold and hot LNG.

(7) In several embodiments, in the structure of (1) or (2) above,

the expansion turbine satisfies the condition of (B),

the floating body type device is provided with:

a condenser provided on a downstream side of the expansion turbine in the thermodynamic cycle, for condensing the heat medium;

a pump provided downstream of the condenser in the thermodynamic cycle, for pressurizing the heat medium; and

an evaporator provided downstream of the pump in the thermodynamic cycle for evaporating the heat medium,

The condenser includes the first heat exchanger configured to condense the thermal medium by heat exchange with the liquefied natural gas.

According to the configuration of (7), in the floating body facility, the expansion turbine in the thermodynamic cycle in which LNG from the LNG tank provided on the floating body is used as a low-temperature heat source can be driven. That is, the expansion turbine is supplied not with the gas from the LNG tank but with the heat medium as the working fluid of the thermodynamic cycle. Therefore, the LNG from the expansion turbine can be prevented from leaking, and the power generation can be performed using the cold and hot heat of the LNG.

Further, according to the configuration of (7) above, the pressure of the heat medium in the thermodynamic cycle can be set irrespective of the feed pressure of the regasified LNG (supply pressure to a required target), and thus can be applied to a wide range of LNG feed pressures.

(8) In several embodiments, in the structure of (7) above,

the floating body facility is provided with an internal combustion engine capable of being supplied with fuel gas from the liquefied natural gas stored in the LNG tank,

the evaporator is configured to evaporate the heat medium using waste heat of the internal combustion engine.

According to the configuration of the above (8), since the waste 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, it is possible to effectively utilize the waste heat of the internal combustion engine and to effectively perform power generation.

(9) In several embodiments, in the structure of (7) or (8) above,

the internal combustion engine is configured such that the regasified LNG from the first heat exchanger is supplied to the internal combustion engine as fuel.

According to the configuration of the above (9), LNG regasified by heat exchange between the first heat exchanger, which is a condenser in the thermodynamic cycle, and the heat medium is supplied as fuel to the internal combustion engine, so that the floating body device can be operated effectively.

(10) In several embodiments, in the structure of (1) or (2) above,

the expansion turbine satisfies the condition of (B),

the floating body type device is provided with:

a first cooler provided on a downstream side of the expansion turbine in the thermodynamic cycle, for cooling the heat medium;

A compressor provided on a downstream side of the first cooler in the thermodynamic cycle for compressing the heat medium; and

a heater provided on a downstream side of the compressor in 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 configuration of (10) above, in the floating body facility, the expansion turbine in the thermodynamic cycle in which LNG from the LNG tank provided on the floating body is used as a low-temperature heat source can be driven. That is, the expansion turbine is supplied not with the gas of LNG from the LNG tank but with a heat medium that is a working fluid of the thermodynamic cycle. Therefore, the LNG from the expansion turbine can be prevented from leaking, and the power generation can be performed using the cold and hot heat of the LNG.

In the case of an LNG tanker equipped with a turbine or a compressor, the structure of (10) can be obtained by forming a thermodynamic cycle by using an existing apparatus (turbine or compressor). Therefore, the facility cost can be suppressed, and the power generation can be efficiently performed by using the cold and hot heat of LNG.

(11) In several embodiments, in the structure of (10) above,

the floating body apparatus further includes a rotation shaft connecting the expansion turbine and the compressor,

the compressor is configured to be driven by the expansion turbine via the rotary shaft.

According to the structure of the above (11), the compressor and the expansion turbine in the thermodynamic cycle are connected via the rotary shaft. Therefore, in the LNG tanker, when an apparatus (e.g., a supercharger) including a compressor and a turbine connected by a rotation shaft is used, the apparatus is used to form a thermodynamic cycle, whereby the floating apparatus according to the result of (10) above can be obtained. Therefore, the equipment cost can be suppressed, and the LNG can be efficiently used for power generation by using the heat and cold of the LNG.

(12) In several embodiments, in the structure of (10) or (11) above,

the heater is configured to heat the heat medium using waste heat of the internal combustion engine.

According to the configuration of (12) above, since the waste 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 waste heat of the internal combustion engine can be effectively utilized and power generation can be effectively performed.

(13) In several embodiments, any one of the structures (10) to (12) above includes:

an internal combustion engine configured to be able to be supplied with a fuel gas from the liquefied natural gas stored in the LNG tank; and

a second cooler disposed between the expansion turbine and the first cooler in 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 of (13), since the heat medium of the thermodynamic cycle is further cooled by heat exchange with LNG from the LNG tank in the second cooler, power generation can be more effectively performed by utilizing the heat and cold of LNG.

(14) In several embodiments, in any one of the structures (1) to (13) above,

the expansion turbine comprises: a rotor, a housing surrounding the rotor, and a seal portion that suppresses leakage of fluid through a gap between the rotor and the housing,

the seal unit is configured to be supplied with an inert gas at a higher pressure than the regasified LNG or the heat medium supplied to the expansion turbine.

According to the configuration of (14) above, 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, even if the operation mode of the floating facility is changed, the type of fluid supplied to the expansion turbine is changed, and thus, it is possible to perform an appropriate shaft seal without changing the structure of the seal portion.

(15) In several embodiments, in any one of the structures (1) to (14) above,

the floating body apparatus further includes a generator configured to be driven by the expansion turbine.

According to the configuration of (15), the expansion turbine can be driven by the cold and hot heat of the LNG stored in the LNG tank provided on the floating body, and the generator can be driven by the expansion turbine. Therefore, power generation can be performed using the cold and hot LNG, and the energy conversion efficiency of the entire floating body plant can be improved.

(16) A method for manufacturing a floating body facility according to at least one embodiment of the present invention is a method for manufacturing a floating body facility according to any one of the above structures (1) to (15) by reforming an LNG ship having a hull, a main body provided to the hull, and an LNG tank provided to the hull, and includes the steps of:

A step of providing a first heat exchanger for vaporizing liquefied natural gas in the LNG tank by heat exchange to obtain regasified LNG; and

a step of forming a regasified LNG supply line that guides the regasified LNG to a gas facility,

in order for the main unit or a turbine constituting a part of a thermodynamic cycle for recovering waste heat of the main unit to function as an expansion turbine, the first heat exchanger satisfies the following condition (a) or (B) in relation to the expansion turbine:

(A) Configured to drive the expansion turbine with the regasified LNG from the first heat exchanger;

(B) Is configured to form part of a thermodynamic cycle that utilizes the liquefied natural gas as a low temperature heat source in the first heat exchanger and to drive the expansion turbine through the heat medium in a gaseous state.

According to the method of the above (16), the first heat exchanger is provided in the LNG ship including the main unit or the turbine constituting a part of the thermodynamic cycle so that the turbine functions as an expansion turbine and the regasified LNG supply line is formed, whereby the floating body facility having the structure of the above (1) can be manufactured. According to the floating plant thus obtained, power generation can be performed by utilizing the heat and cold of LNG, and the energy conversion efficiency of the entire floating plant can be improved.

Effects of the invention

According to at least one embodiment of the present invention, there are provided a floating body type device capable of improving energy conversion efficiency and a method for manufacturing the floating body type device.

Drawings

Fig. 1 is a schematic view of a floating body plant according to an embodiment.

Fig. 2A is a schematic configuration diagram showing an LNG tanker corresponding to the floating body facility shown in fig. 2B.

Fig. 2B is a schematic configuration diagram showing a floating body type device according to an embodiment.

Fig. 3A is a schematic configuration diagram showing an LNG tanker corresponding to the floating body facility shown in fig. 3B and 3C.

Fig. 3B is a schematic configuration diagram showing a floating body type device according to an embodiment.

Fig. 3C is a schematic configuration diagram showing a floating body type device according to an embodiment.

Fig. 4A is a schematic configuration diagram showing an LNG tanker corresponding to the floating body facility shown in fig. 4B.

Fig. 4B is a schematic configuration diagram showing a floating body type device according to an embodiment.

Fig. 5A is a schematic configuration diagram showing an LNG tanker corresponding to the floating body facility shown in fig. 5B.

Fig. 5B is a schematic configuration diagram showing a floating body facility according to an embodiment.

Fig. 6 is a schematic view of an expansion turbine according to an embodiment.

Fig. 7A is a schematic configuration diagram showing an LNG tanker corresponding to the floating body facility shown in fig. 7B.

Fig. 7B is a schematic configuration diagram showing a floating body facility according to an embodiment.

Fig. 8A is a schematic configuration diagram showing an LNG tanker corresponding to the floating body facility shown in fig. 8B.

Fig. 8B is a schematic configuration diagram showing a floating body facility according to an embodiment.

Fig. 9A is a schematic configuration diagram showing an LNG tanker corresponding to the floating body facility shown in fig. 9B.

Fig. 9B is a schematic configuration diagram showing a floating body facility according to an embodiment.

Fig. 10A is a schematic configuration diagram showing an LNG tanker corresponding to the floating body facility shown in fig. 10B.

Fig. 10B is a schematic configuration diagram showing a floating body facility according to an embodiment.

Fig. 11A is a schematic configuration diagram showing an LNG tanker corresponding to the floating body facility shown in fig. 11B.

Fig. 11B is a schematic configuration diagram showing a floating body facility according to an embodiment.

Detailed Description

Several embodiments of the present invention are described below with reference to the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the constituent parts described as the embodiments or shown in the drawings are not intended to limit the scope of the present invention to these, but are merely illustrative examples.

Fig. 1 is a schematic view of a floating body plant according to an embodiment. The floating body facility 100 shown in fig. 1 is a Facility (FSRU) for storing and regasifying LNG. The floating body type apparatus 100 is obtained by, for example, modifying an Liquefied Natural Gas (LNG) tanker 101 (LNG ship) for transporting LNG. In fig. 1, elements included in the LNG tanker 101 before the rebuilding are indicated by solid lines, and elements added by the rebuilding are indicated by broken lines.

As shown in fig. 1, the LNG tanker 101 before the rebuilding includes: a hull 2 (floating body), a main body 4 provided to the hull 2, and an LNG tank 6 provided to the hull 2. The hull 2 has a bow 2a and a stern 2b, the bow 2a having a shape for reducing resistance of the hull from a fluid such as sea water, and the stern being capable of mounting a rudder 3 for adjusting the proceeding direction of the hull 2. The main body 4 is a body for generating power for driving a propeller 5 as a propeller. The LNG tanker 101 shown in fig. 1 includes an engine 16 and a turbine 40 as a main body 4.

LNG tanker 101 may also further comprise a thermodynamic cycle (e.g., rankine cycle, brayton cycle, etc.) for recovering waste heat of host authority 4 (e.g., engine 16). The thermodynamic cycle is described later.

The floating body facility 100 obtained by modifying the LNG tanker 101 further includes a first heat exchanger 8 for vaporizing LNG in the LNG tank 6 by heat exchange, and an expansion turbine 18 driven by the cold and hot heat of the LNG. In the exemplary embodiment shown in fig. 1, turbine 40 also functions as expansion turbine 18. The floating body facility 100 further includes a first LNG line 10 for introducing LNG from the LNG tank 6 into the first heat exchanger 8 and/or a second LNG line 12 for introducing regasified LNG from the first heat exchanger 8 into the expansion turbine. The floating body facility 100 further includes a regasified LNG supply line 14 for introducing regasified LNG from the expansion turbine 18 into a gas facility (a target of need).

In addition, the floating body plant 100 may be modified to provide LNG tankers 101. That is, the facility including the same hull 2 may be operated as the LNG tanker 101, or may be operated as the floating body facility 100 (FSRU), and the operation of the LNG tanker 101 and the operation of the floating body facility 100 may be switched between each other by modification.

Hereinafter, the floating body type facility 100 and the LNG tanker 101 according to several embodiments will be described in more detail.

Fig. 2A, 3A, 4A, and 5A (hereinafter, also referred to as fig. 2A to 5A) are schematic configuration diagrams showing the LNG tankers 101 before being retrofitted to the floating body facility 100 according to one embodiment.

Fig. 2B, 3C, 4B, and 5B (hereinafter, also referred to as fig. 2B to 5B) are schematic configuration diagrams showing a floating body facility 100 obtained by reforming the LNG tanker 101 shown in fig. 2A to 5A, respectively.

In the drawings subsequent to fig. 2A, the hull 2 (floating body) is not shown.

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

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

The 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 the motor 66 (see fig. 3A) via the power line 56. Then, the motor drives the propeller 5B (see fig. 3A) to rotate via the gear 58B (see fig. 3A). As shown in fig. 3A, the power line 56 may be provided with a transformer 62, a converter 64, and other devices as appropriate.

The engine 16 may be configured to be able to be supplied with a gas (boil-off gas or the like) from LNG as fuel, and to be able to be supplied with an oil fuel (for example, light oil) as fuel via the oil supply line 26.

The boiler 32 is configured to burn a supplied fuel (evaporated gas) and generate steam by combustion heat thereof. 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 be supplied with a gas (boil-off gas or the like) from LNG as fuel, and to be able to be supplied with an oil fuel (for example, light oil) as fuel via the oil supply line 36.

In the exemplary embodiment shown in fig. 2A and 4A, the generator 54 is connected to the turbine 40, the turbine 40 is driven to rotate by steam from the boiler 32, and the generator 54 is driven by the turbine 40 to generate electricity. The electric power generated in this way is transmitted to the motor via the power line, and the propeller 5 is driven via the motor, similarly to the electric power generated by the generator 28 connected to the engine 16.

In the exemplary embodiment shown in fig. 3A and 5A, the propeller 5A is connected with the turbine 40 via a gear 58A. Then, the rotational energy of the rotation shaft of the turbine 40 is transmitted to the propeller 5A via the gear 58A, thereby driving the propeller 5A.

In addition, the propeller 5 of the LNG tanker 101 may include a port side propeller 5A and a starboard side propeller 5B. Both the port side propeller 5A and the starboard side propeller 5B may 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 motor 66 (see fig. 3A), and the other may be driven by the turbine 40 via a gear.

In addition, the turbine 40 may have multiple stages of turbines with different inlet pressures. In the exemplary embodiment shown in fig. 2A-5A, the turbine 40 includes 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 46 having a lower inlet pressure than the intermediate pressure turbine 44, respectively.

The high-pressure turbine 42 has an outlet portion that can communicate with the inlet side of the intermediate-pressure turbine, and includes turbine blades shorter than the intermediate-pressure turbine.

The low pressure turbine 46 has an inlet portion 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, the high pressure turbine 42, the intermediate pressure turbine 44, and the low pressure turbine 46 are disposed on a shaft, driving the generator 54 via a common rotating shaft.

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

In the exemplary embodiment shown in fig. 2A-5A, steam from the steam supply line 38 is supplied to the inlet of the high pressure turbine 42. The steam discharged from the high-pressure turbine 42 is supplied to the reheater 34 via the reheater inlet line 50 and reheated. The reheated steam from the reheater 34 is then supplied to the inlet of the intermediate pressure turbine 44 via a 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 water return (not shown).

In the floating Facility (FSRU) 100 shown in fig. 2B to 5B, the electric power used in the floating facility 100 is generated by using the engine 16, and the engine 16 has a function as the main body 4 when it is used as the LNG tanker 101 (before the rebuilding, refer to fig. 2A to 5A). Further, by operating the turbine 40 as the expansion turbine 18, electric power used in the floating body facility 100 is generated, and the turbine 40 has a function as the main body 4 when operating as the LNG carrier 101.

In the floating body facility 100 shown in fig. 2B to 5B, the 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 case of operation as the LNG tanker 101. The generator 28 is connected to the engine 16, and the generator 28 is driven by the engine 16 to generate electric power. The power generated by the generator 28 supplies power to the desired target in the floating device 100 via the power line.

In addition, the floating body facility 100 shown in fig. 2B to 5B is provided with a first heat exchanger 8, and the first heat exchanger 8 is configured to gasify Liquefied Natural Gas (LNG) from the LNG tank 6 to obtain regasified LNG.

The floating body type apparatus 100 shown in fig. 2B to 5B includes: a first LNG line 10 for guiding LNG from the LNG tank 6 to the first heat exchanger 8 and a second LNG line 12 for guiding regasified LNG from the first heat exchanger 8 to the expansion turbine. The first LNG line 10 is provided with an LNG pump 72 for pressurizing the liquid LNG. The floating body apparatus 100 further includes a cooling water line 74 through which cooling water for cooling the engine 16 flows, and the cooling water after cooling the engine 16 is guided to the first heat exchanger 8 via the cooling water line 74.

The first heat exchanger 8 is configured to generate regasified LNG by heating and vaporizing the liquid LNG introduced from the first LNG line 10 by heat exchange with cooling water (heat medium) flowing through the cooling water line 74. The regasified LNG generated by the first heat exchanger 8 is supplied to the expansion turbine 18 (turbine 40) via the second LNG line, and the thus supplied regasified LNG drives the expansion turbine 18 and drives the generator 54 connected to the expansion turbine 18.

The regasified LNG discharged from the expansion turbine 18 (turbine 40) is directed to a gas plant (a desired target) via the regasified LNG supply line 14.

In the above-described embodiment, in the floating body Facility (FSRU) 100 capable of storing and regasifying the liquefied natural gas stored in the LNG tank 6, the expansion turbine 18 can be driven by the cold and hot heat of the LNG stored in the LNG tank 6 provided on the hull 2. Therefore, by driving the generator 54 by the expansion turbine 18, power generation can be performed by using the cold and hot LNG, and the energy conversion efficiency of the entire floating body plant 100 can be improved.

The expansion turbine 18 in the above embodiment can be used as a turbine 40, and the turbine 40 serves as the main engine 4 for generating the propulsion of the hull 2. Therefore, the LNG tanker 101 (see fig. 2A to 5A) having the turbine 40 usable as the main unit 4 can be modified to be operated as the floating Facility (FSRU) 100. Therefore, for example, the floating facility 100 can be effectively utilized by switching between the operation as the LNG tanker 101 and the operation as the floating Facility (FSRU) 100 according to the LNG demand or the like.

In the above embodiment, the LNG tanker 101 having the engine 16 (internal combustion engine) usable as the host facility 4 can be modified to be operated as the floating Facility (FSRU) 100. Therefore, for example, in connection with the LNG demand, etc., the operation of the LNG tanker 101 and the FSRU can be switched, and thus the floating facility 100 can be effectively utilized.

In the above embodiment, the heat medium that exchanges heat with LNG in the first heat exchanger 8 includes cooling water that cools the engine 16. In this way, since the LNG from the LNG tank 6 is regasified using the cooling water of the engine 16 as a heat medium, the waste heat of the engine 16 can be effectively utilized to effectively generate power.

In the exemplary embodiment shown in fig. 2B, 3B, and 3C, the intermediate-pressure turbine 44 of the high-pressure turbine 42, the intermediate-pressure turbine 44, and the low-pressure turbine 46 constituting the turbine 40 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 via the high pressure turbine 42. 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. In fig. 2B and 3B, the low-pressure turbine 46 is not illustrated.

In the case where the turbine 40 is used as the main body 4 when the LNG tanker 101 is operated, and in the case where the turbine 40 is used as the expansion turbine 18 for power generation when the floating body Facility (FSRU) 100 is operated, there are cases where the volumes of the fluids supplied to the turbine 40 are different.

In this regard, the expansion turbine 18 of the above-described embodiment is an intermediate pressure turbine 44 configured to be supplied with a fluid 44 at a lower pressure than the fluid supplied to the high pressure turbine 42. That is, in the above-described embodiment, in the floating body Facility (FSRU) 100, the regasified LNG flows in from the middle stage of the turbine 40, and therefore, the volume flow rate zone in the expansion turbine 18 is easily matched with that in operation as the LNG tanker 101. Accordingly, in the floating body apparatus 100, the expansion turbine 18 can be appropriately driven.

The expansion turbine 18 of the above embodiment is an intermediate-pressure turbine 44 configured to be supplied with a 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 body Facility (FSRU) 100, the regasified LNG is discharged from the middle stage of the turbine 40, and therefore, the volume flow rate zone in the expansion turbine 18 is easily matched with that in operation as the LNG tanker 101. Accordingly, in the floating body apparatus 100, the expansion turbine 18 can be appropriately driven.

In this way, by using only a middle stage of the turbine 40 (the intermediate-pressure turbine 44 in the above embodiment) as the expansion turbine 18 driven by the regasified LNG, it is possible to further generate power using other parts of the turbine 40.

For example, in the exemplary embodiment shown in fig. 3C, steam from the boiler 32 is supplied to the low-pressure turbine 46 having a rotation axis different from that of the high-pressure turbine 42 and the medium-pressure turbine 44 via a steam supply line 76, and drives the low-pressure turbine 46 and the generator 55 connected to the low-pressure turbine 46. In this way, when used as an FSRU, the low-pressure turbine 46 driven by steam can generate electric power in addition to the expansion turbine 18, and therefore, more electric power can be supplied.

In the exemplary embodiment shown in fig. 4B and 5B, the high pressure turbine 42 and the intermediate pressure turbine 44 function as the expansion turbine 18. That is, the expansion turbine 18 includes a high-pressure turbine 42 (first turbine) and an intermediate-pressure turbine (second turbine) having a lower inlet pressure than the high-pressure turbine 42. The regasified LNG from the first heat exchanger 8 is supplied to a high pressure turbine 42 (first turbine). The regasified LNG discharged from the high pressure turbine 42 (first turbine) is guided to the second heat exchanger 69 via the reheating line 78, and after the second heat exchanger 69 is heated by heat exchange with the heat medium, the LNG is supplied to the inlet of the intermediate pressure turbine 44.

The cooling water from the cooling water line 74 (cooling water after cooling the engine 16) is led to the second heat exchanger 69 as shown in fig. 4B and 5B as a heat medium for reheating the regasified LNG. The first heat exchanger 8 and the second heat exchanger 69 may have a structure in which they share a single housing as shown in fig. 4B and 5B, or may have respective housings.

In the above embodiment, the expansion turbine 18 has a structure of a reheat turbine including the high pressure turbine 42 (first turbine) and the intermediate pressure turbine 44 (second turbine) to which the fluid discharged from the high pressure turbine 42 (first turbine) and heated by the second heat exchanger 69 is supplied. Therefore, when the reheat turbine (turbine 40) is used as the main unit 4, as in the LNG tanker 101 shown in fig. 4A and 5A, the reheat turbine can be used as the expansion turbine 18 when the reheat turbine is used as the floating body Facility (FSRU) 100 in its original configuration. Therefore, the facility cost can be suppressed, and the power generation can be efficiently performed using the cold and hot LNG.

The method of retrofitting the LNG tanker 101 shown in fig. 2A-5A to obtain the floating body apparatus 100 shown in fig. 2B-5B comprises the steps of: a step of providing the LNG tanker 101 with a first heat exchanger 8 for vaporizing LNG in the LNG tank 6 by heat exchange, and a step of providing a regasified LNG supply line 14 for guiding the regasified LNG generated in the first heat exchanger 8 to a gas facility (a required target). In order for the turbine 40 constituting the main unit 4 to function as the expansion turbine 18, the relationship between the first heat exchanger 8 and the expansion turbine 18 is set so as to satisfy the following condition (a).

(A) The expansion turbine 18 is configured to be driven by the regasified LNG from the first heat exchanger 8.

In addition, the method for reforming the LNG tanker can further comprise the following steps: a step of providing a first LNG line 10 for guiding LNG from the LNG tank 6 to the first heat exchanger 8, and a step of providing a second LNG line 12 for guiding regasified LNG from the first heat exchanger 8 to the expansion turbine.

In addition, the method for reforming the LNG tanker can further comprise the following steps: a step of providing a cooling water line for guiding cooling water after cooling the engine 16 to the first heat exchanger 8.

In addition, in the case where the floating body type apparatus 100 shown in fig. 3B and 5B is obtained from the LNG tanker 101 shown in fig. 3A and 5A, the following steps may be included: a step of separating the gear 58A and the propeller 5A connected to the turbine 40 from the turbine 40, and connecting the generator 54 to the turbine 40.

In the case where the floating body type apparatus 100 shown in fig. 4B and 5B is obtained from the LNG tanker 101 shown in fig. 4A and 5A, the following steps may be further included: a step of providing a second heat exchanger 69 and a step of providing a reheat circuit 78 extending from the outlet of the high pressure turbine 42 (first turbine) to the inlet of the intermediate pressure turbine 44 (second turbine) via the second heat exchanger 69.

By reforming the LNG tanker 101 according to the reforming method described above, the floating body type facility 100 of the embodiment shown in fig. 2B to 5B can be obtained, for example. According to the floating facility 100 thus obtained, power generation can be performed by using the cold and hot heat of LNG, and the energy conversion efficiency of the entire floating facility can be improved.

Fig. 6 is a schematic diagram of an expansion turbine 18 (for example, the expansion turbine 18 shown in fig. 2B to 5B) according to several embodiments. The expansion turbine 18 shown in fig. 6 includes: the rotor 19, the housing 18a surrounding the rotor 19, and the seal 80, the seal 80 being for suppressing leakage of fluid (regasified LNG in the case of the expansion turbine 18 of fig. 2B to 5B) through a gap between the rotor 19 and the housing 18 a.

The seal portion 80 includes a plurality of labyrinth portions 82A to 82C provided at intervals in the axial direction. Further, at a position between the labyrinth portions 82B, 82C adjacent to each other, an inert gas (for example, nitrogen) is supplied to a space 83A formed between the rotor 19 and the housing 18a via an inert gas supply line 84 and branch lines 84a, 84B. The pressure of the inert gas supplied to the space 83A is higher than the pressure of the fluid supplied to the expansion turbine 18 (regasified LNG in the case of the expansion turbine 18 of fig. 2B to 5B).

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

That is, an inert gas (for example, nitrogen) having a higher pressure than the fluid supplied to the expansion turbine 18 (regasified LNG in the case of the expansion turbine 18 of fig. 2B to 5B) is supplied to the seal portion 80.

According to the above configuration, since the 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, for example, even if the operation mode between the floating facility 100 and the LNG tanker 101 is changed, the type of fluid supplied to the expansion turbine 18 is changed, and therefore, it is possible to perform appropriate shaft sealing without changing the structure of the seal portion 80.

Fig. 7A, 8A, 9A, 10A, and 11A (hereinafter, also referred to as fig. 7A to 11A) are schematic configuration diagrams showing the LNG tanker 101 before being modified into the floating body type facility 100 according to one embodiment.

Fig. 7B, 8B, 9B, 10B, and 11B (hereinafter, also referred to as fig. 7B to 11B) are schematic configuration diagrams showing a floating body facility 100 obtained by reforming the LNG tanker 101 shown in fig. 7A to 10A, respectively.

The LNG tanker 101 shown in fig. 7A to 11A is equipped with an engine 16 (internal combustion engine) as the main unit 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 pressurizing LNG to an appropriate pressure and a valve 89 for adjusting the flow rate of LNG supplied to the engine 16. The engine 16 is configured to drive the propeller 5 (propeller) to rotate. The rotational energy generated by the engine 16 may be transmitted to the propeller 5 via a gear (not shown), or the motor may be driven by electric power generated by driving a generator (not shown) by the engine 16, and the propeller 5 may be driven by the motor.

In the exemplary embodiment shown in fig. 7A and 8A, a thermodynamic cycle 102 is provided at the LNG tanker 101, the thermodynamic cycle 102 comprising a circuit 104 for the flow of a heat medium as a working fluid. The thermodynamic cycle 102 is a rankine cycle comprising: an expansion turbine 18 provided in the circuit 104, a condenser 106 provided on the downstream side of the expansion turbine 18, a pump 108 provided on the downstream side of the condenser 106, and an evaporator 110 provided on the downstream side of the pump 108. The expansion turbine 18 is connected to an electric generator 113.

The expansion turbine 18 is configured to expand a heat medium flowing through the circuit 104 of the thermodynamic cycle 102, and thereby, the generator 113 is driven to generate electric 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. As the low-temperature heat source, for example, sea water can be used.

The pump 108 is configured to boost the pressure of the heat medium condensed in the condenser 106 and made into a liquid.

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. As the high-temperature heat source, exhaust gas of the engine 16 can be used, for example. In fig. 7A and 8A, the exhaust gas from the engine 16 is supplied to the evaporator 110 via the exhaust line 92.

In the thermodynamic cycle 102 configured as described above, the generator 113 can be driven by the waste heat of the engine 16 recovered by heat exchange in the evaporator 110.

In the floating body facility 100 shown in fig. 7B and 8B, a condenser 106 constituting a thermodynamic cycle 102 that operates when the LNG tanker 101 is operated (before the rebuilding, see fig. 7A to 8A) is used as the first heat exchanger 8.

The floating body apparatus 100 shown in fig. 7B and 8B includes: the LNG pump 72 is provided in the first LNG line 10 for guiding the LNG from the LNG tank 6 to the first heat exchanger 8 and for pressurizing the liquid LNG, and the valve 71 is provided for adjusting the flow rate of the LNG in the first LNG line 10. The regasified LNG generated in the first heat exchanger 8 is led to a gas facility (a target to be required) via a regasified LNG supply line 14.

As a low-temperature heat source of the thermodynamic cycle 102, LNG from the LNG tank 6 is supplied to a condenser 106 (first heat exchanger 8) constituting the thermodynamic cycle 102 via the first LNG line 10. 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 driven by a heat medium in a gaseous state passing through the condenser 106 (the first heat exchanger 8), the pump, and the evaporator 110.

According to the embodiment described above, in the floating body plant 100, the expansion turbine 18 in the thermodynamic cycle 102 in which LNG from the LNG tank 6 provided on the hull 2 is used as a low-temperature heat source can be driven. That is, the expansion turbine 18 is not supplied with the gas of the LNG from the LNG tank 6, but with a heat medium as the working fluid of the thermodynamic cycle 102. Accordingly, the LNG from the expansion turbine 18 can be prevented from leaking, and the power generation can be performed using the cold and hot heat of the LNG.

Further, according to the above embodiment, unlike the case where regasified LNG is directly expanded in the expansion turbine, the pressure of the heat medium in the thermodynamic cycle 102 can be set irrespective of the supply pressure of regasified LNG (supply pressure to a required target), and thus can be applied to a wide range of LNG supply pressures, for example, to a high-pressure supply pressure such as 10 to 15 MPa.

In addition, when the regasified LNG is directly expanded in the expansion turbine (for example, see fig. 2B to 5B), if the supply pressure of the regasified LNG is set to be high, the inlet pressure of the expansion turbine 18 needs to be increased accordingly, and therefore, it may be difficult to achieve the required supply pressure.

In the floating body facility 100 according to the above embodiment, the evaporator 110 constituting the thermodynamic cycle 102 is configured to evaporate the heat medium by using waste heat of the engine 16 supplied with the fuel gas (gas supplied via the LNG fuel supply line 88) from the LNG stored in the LNG tank 6.

In this way, since the waste 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 waste heat of the engine 16 can be effectively utilized, and power generation can be effectively performed.

In the exemplary embodiment shown in fig. 7B and 8B, the exhaust gas of the engine 16 is used as the high-temperature heat source described above, but in other embodiments, the high-temperature heat source may be cooling water after cooling the engine 16.

In other embodiments, the high-temperature heat source may be sea water or the like.

In the exemplary embodiment shown in fig. 8A, the LNG tanker 101 (floating body facility 100) has an engine 16 to which fuel gas (gas supplied via the LNG fuel supply line 88) from LNG stored in the LNG tank 6 is supplied. The engine 16 is configured to be fueled by regasified LNG from the first heat exchanger 8 (i.e., condenser 106).

In the above embodiment, 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 as fuel to the engine 16, and therefore the LNG tanker 101 (floating body plant 100) can be operated efficiently.

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

Air is supplied to the compressor 94 via an air intake line 114. Compressed air generated by the compressor 94 is supplied to the engine 16 via an engine inlet line 116. Exhaust gas generated in the engine 16 by combustion of the fuel is discharged from the engine 16 via an engine outlet line 118 and sent to the turbine 96. Turbine 96 is driven by exhaust gas from engine 16, thereby driving generator 113 to generate electrical power. The exhaust gas that has completed work at the turbine 96 is discharged from the exhaust line 120.

In the embodiment shown in fig. 9A and 10A, a heat exchanger 98 (a second cooler, which will be described later) for regasifying LNG is provided in the LNG fuel supply line 88 for supplying LNG from the LNG tank 6 to the engine 16.

In the exemplary embodiment shown in fig. 9A, the heat exchanger 98 (second cooler) is configured to heat and gasify LNG by heat exchange with seawater introduced via line 99.

In the exemplary embodiment shown in fig. 10A, the heat exchanger 98 (second cooler) is configured to heat and gasify LNG by heat exchange with air introduced via line 99. In the exemplary embodiment shown in fig. 10A, the air after passing through the heat exchanger 98 (second cooler) is supplied to the compressor 94 via the air introduction line 114.

In the floating body facility 100 shown in fig. 9B and 10B, a thermodynamic cycle 122 is formed, and the thermodynamic cycle 122 includes the compressor 94 and the turbine 96 of the supercharger 93 used in operation as the LNG tanker 101 (before the rebuilding, refer to fig. 9A to 10A). The thermodynamic cycle 122 is a brayton cycle that does not accompany a phase change of a heat medium (working fluid).

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

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

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

The floating body apparatus 100 shown in fig. 9B and 10B includes: the LNG pump 72 is provided in the first LNG line 10 for guiding LNG from the LNG tank 6 to the first heat exchanger 8 and for pressurizing liquid LNG, and the valve 71 is provided for adjusting the flow rate of LNG in the first LNG line 10. The regasified LNG generated in the first heat exchanger 8 is led to a gas facility (a target to be required) via a regasified LNG supply line 14.

As a low-temperature heat source of the thermodynamic cycle 122, LNG from the LNG tank 6 is supplied to a first cooler 126 (first heat exchanger 8) constituting the thermodynamic cycle 122 via the first LNG line 10. 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 driven by the heat medium in a gaseous state after passing through the first cooler 126.

According to the embodiment described above, in the floating body facility 100, the turbine 96 (expansion turbine) in the thermodynamic cycle 122 in which LNG from the LNG tank 6 provided on the hull 2 is used as a low-temperature heat source can be driven. That is, the expansion turbine 18 is not supplied with the gas of the LNG from the LNG tank 6, but with a heat medium as the working fluid of the thermodynamic cycle 122. Accordingly, the LNG from the expansion turbine 18 can be prevented from leaking, and the power generation can be performed using the cold and hot heat of the LNG.

In the case of the LNG tanker 101 equipped with the turbine 96 or the compressor 94, the configuration of the above-described embodiment can be obtained by constructing the thermodynamic cycle 122 by using existing equipment (the turbine 96 or the compressor 94, or the booster 93). Therefore, the facility cost can be suppressed, and the power generation can be efficiently performed by using the cold and hot heat of LNG.

In the above embodiment, the floating body apparatus 100 includes the rotary shaft 95 connecting the turbine 96 (the expansion turbine 18) and the compressor 94, and the compressor 94 is configured to be driven by the turbine 96 (the expansion turbine 18) via the rotary shaft 95.

In this way, the compressor 94 and the turbine 96 (the expansion turbine 18) in the thermodynamic cycle 122 are connected via the rotary shaft 95. Therefore, in the LNG tanker 101, when an apparatus (the above-described supercharger 93) including the compressor 94 and the turbine 96 connected by the rotary shaft 95 is used, the thermodynamic cycle 122 is formed by using the apparatus, whereby the floating body apparatus 100 of the above-described embodiment can be obtained. Therefore, the equipment cost can be suppressed, and the LNG can be efficiently used for power generation by using the heat and cold of the LNG.

In the floating body facility 100 according to the above embodiment, the heater 128 constituting the thermodynamic cycle 122 is configured to evaporate the heat medium by using waste heat of the engine 16 supplied with the fuel gas (gas supplied via the LNG fuel supply line 88) from the LNG stored in the LNG tank 6.

In this way, since the waste 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 waste heat of the engine 16 can be effectively utilized and power generation can be effectively performed.

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

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

In this way, the heat medium of the thermodynamic cycle 122 is further cooled by heat exchange with the LNG from the LNG tank 6 in the heat exchanger 98 (second cooler), and therefore, power generation can be more effectively performed by utilizing the cold and hot heat of the LNG.

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

In the exemplary embodiment shown in fig. 11B, an expansion turbine 136 (18) is provided in the branch line 132 branched from the LNG fuel supply line 88. A valve 134 for adjusting the flow rate of the regasified LNG supplied to the expansion turbine 136 is provided in the branch line 132. The expansion turbine 136 is connected to an electric generator 138. The regasified LNG is supplied to the expansion turbine 136 via the branch line 132, and the regasified LNG is expanded by the expansion turbine 136, and the generator 138 is driven. In this way, electric power is generated by the generator 138. The regasified LNG discharged from the expansion turbine 136 is subjected to temperature adjustment by the heat exchanger 140, and then is guided to a gas facility (a desired target) via the regasified LNG supply line 14.

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

The expansion turbine 18 is configured to expand a heat medium flowing through the circuit 104 of the thermodynamic cycle 102, thereby driving the generator 113 to generate electric power.

As a low-temperature heat source of the thermodynamic cycle 102, LNG from the LNG tank 6 is supplied to a condenser 106 (first heat exchanger 8) constituting the thermodynamic cycle 102 via the LNG fuel supply line 88. That is, the condenser 106 is configured to condense the heat medium of the thermodynamic cycle 102 by heat exchange with LNG. Then, the expansion turbine 112 is driven by the heat medium in a gaseous state passing through the condenser 106 (the first heat exchanger 8), the pump 108, and the evaporator 110.

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. The high temperature heat source is directed to the evaporator 110 via line 107. As the high-temperature heat source, exhaust gas of the engine 16 and cooling water of the engine 16 can be used, for example. In addition, seawater may be used as a high temperature heat source.

In the above-described embodiment, the expansion turbine 136 and the expansion turbine 112 are used together, the expansion turbine 136 being driven by the regasified LNG from the first heat exchanger 8 (heat exchanger 98), the expansion turbine 112 forming part of the thermodynamic cycle 102 that utilizes LNG as a low temperature heat source, and being driven by a gaseous heat medium. This can increase the power recovered from the LNG cold and heat.

The method of retrofitting the LNG tanker 101 shown in fig. 6A to 11A to obtain the floating body type plant 100 shown in fig. 2B to 5B includes the steps of: a step of providing a first heat exchanger 8 to the LNG carrier 101, the first heat exchanger 8 being configured to gasify LNG in the LNG tank 6 by heat exchange; and a step of providing a regasified LNG supply line 14, the regasified LNG supply line 14 being for guiding the regasified LNG generated in the first heat exchanger 8 to a gas plant (a required target). In order to make the turbine 40 constituting the main unit 4 function as the expansion turbine 18, the first heat exchanger 8 is provided so as to satisfy the following condition (B) in relation to the expansion turbine 18.

(B) The expansion turbine 18 is configured to be driven by a gaseous heat medium while forming part of the thermodynamic cycles 102 and 122 using the liquefied natural gas as a low-temperature heat source in the first heat exchanger 8.

In addition, the method for reforming the LNG tanker can further comprise the following steps: a step of providing a first LNG line 10 for guiding LNG from the LNG tank 6 to the first heat exchanger 8; and a step of providing a second LNG line 12 for guiding the regasified LNG from the first heat exchanger 8 to the expansion turbine.

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

By reforming the LNG tanker 101 by the reforming method described above, the floating body type facility 100 according to the embodiment shown in fig. 6B to 11B can be obtained, for example. According to the floating plant 100 thus obtained, power generation can be performed by utilizing the heat and cold of LNG, and the energy conversion efficiency of the entire floating plant can be improved.

The embodiments of the present invention have been described above, but the present invention is not limited to the above embodiments, and the present invention also includes a mode in which the above embodiments are modified and a mode in which these modes are appropriately combined.

In the present specification, the expression "in a certain direction", "along a certain direction", "parallel", "orthogonal", "central", "concentric" or "coaxial" and the like means not only such an arrangement but also a state of relative displacement of angles and distances with a tolerance or a degree that the same function can be obtained.

For example, the expression "identical", "equal", and "homogeneous" mean that the objects are in an equal state, and that there is not only a strictly equal state but also a state in which there is a tolerance or a difference of the same degree can be obtained.

In the present specification, the expression "quadrangular shape" and "cylindrical shape" and the like means not only shapes such as a quadrangular shape and a cylindrical shape in a strict sense of geometry, but also shapes including a concave-convex portion, a chamfer portion, and the like within a range where the same effect can be obtained.

In the present specification, the expression "comprising," "including," and "having" one component is not an exclusive expression that excludes the presence of other components.

Symbol description

2. Ship body

2a bow

2b stern

3. Rudder

4. Main unit

5. Propeller propeller

5A port side propeller

5B starboard side screw propeller

6 LNG case

8. First heat exchanger

10. First LNG line

12. Second LNG line

14. Regasification LNG supply line

16. Engine with a motor

18. Expansion turbine

18a shell

19. Rotor

20. Gas supply line

20a first branch line

20b second branch circuit

22. Compressor with a compressor body having a rotor with a rotor shaft

24. Gas collecting tank

26. Oil supply line

28. Electric generator

30. Valve

32. Boiler

34. Reheater

36. Oil supply line

38. Steam supply line

40. Turbine wheel

42. High-pressure turbine

44. Medium pressure turbine

46. Low pressure turbine

48. Backward turbine

50. Reheater inlet line

52. Reheater outlet line

54. Electric generator

55. Electric generator

56. Power transmission line

58A, 58B gear

62. Transformer

64. Converter

66. Motor with a motor housing having a motor housing with a motor housing

69. Second heat exchanger

71. Valve

72 LNG pump

74. Cooling water line

76. Steam supply line

78. Reheat circuit

80. Sealing part

82A, 82B, 82C labyrinth portions

83A, 83B space

84. Inactive gas supply line

84a, 84b branch lines

85. Valve

86. Recovery line

88 LNG fuel supply line

89. Valve

90. Pump with a pump body

92. Exhaust line

93. Supercharger

94. Compressor with a compressor body having a rotor with a rotor shaft

95. Rotary shaft

96. Turbine wheel

98. Heat exchanger

99. Circuit arrangement

100. Floating type equipment

101 LNG tanker

102. Thermodynamic cycle

104. Loop circuit

106. Condenser

107. Circuit arrangement

108. Pump with a pump body

110. Evaporator

112. Expansion turbine

113. Electric generator

114. Air introduction line

116. Engine inlet line

118. Engine outlet line

120. Exhaust line

122. Thermodynamic cycle

124. Loop circuit

126. First cooler

128. Heater

130. Exhaust line

132. Branch line

134. Valve

136. Expansion turbine

138. Electric generator

140. Heat exchanger

Claims

1. A floating body type apparatus, comprising:

a floating body;

an LNG tank provided on the floating body;

a first heat exchanger for vaporizing liquefied natural gas from the LNG tank by heat exchange with a heat medium to obtain regasified LNG;

An expansion turbine satisfying the condition of (a) below: (A) The expansion turbine is configured to be driven by the regasified LNG from the first heat exchanger;

2. The floating body apparatus of claim 1, wherein,

3. The floating body apparatus of claim 2, wherein,

4. A floating body type apparatus, comprising:

a floating body;

an LNG tank provided on the floating body;

5. A floating body type apparatus, comprising:

a floating body;

an LNG tank provided on the floating body;

an expansion turbine satisfying the condition of (a) below: (A) The expansion turbine is configured to be driven by the regasified LNG from the first heat exchanger,

6. A floating body type apparatus, comprising:

a floating body;

an LNG tank provided on the floating body;

an expansion turbine satisfying the condition of (B) below: (B) The expansion turbine is configured to be formed as a part of a thermodynamic cycle using the liquefied natural gas as a low-temperature heat source in the first heat exchanger and driven by the heat medium in a gaseous state;

the first cooler comprises the first heat exchanger configured to cool the heat medium by heat exchange with the liquefied natural gas,

7. The floating body apparatus of claim 6, wherein,

8. A floating body type apparatus, comprising:

a floating body;

an LNG tank provided on the floating body;

the floating body type device is provided with:

9. Float apparatus according to any one of claims 1 to 8, characterized in that,

10. Float apparatus according to any one of claims 1 to 8, characterized in that,

11. A method for manufacturing a floating facility by reforming an LNG ship comprising a hull, a main body provided to the hull, and an LNG tank provided to the hull,

the floating body type device is provided with:

a floating body;

an LNG tank provided on the floating body;

an expansion turbine that satisfies the following conditions: is configured to be driven by the regasified LNG from the first heat exchanger or is configured to form part of a thermodynamic cycle that utilizes the liquefied natural gas as a low temperature heat source in the first heat exchanger and is driven by the heat medium in a gaseous state,

the method for manufacturing the floating body type device comprises the following steps:

A step of providing a first heat exchanger for vaporizing liquefied natural gas from the LNG tank by heat exchange to obtain regasified LNG; and