CN114212197A - LNG low-temperature floating type conveying system and method - Google Patents

Abstract

The invention relates to an LNG low-temperature floating type conveying system and method, which comprises a floating type transfer barge platform, an LNG low-temperature floating hose and an LNG non-heat-insulation hose, and is matched with an emergency separation system, a leakage monitoring system and a falling prevention system, wherein one end of the floating type transfer barge platform is connected with a pipe orifice fixed on land or on an LNG loading ship through the LNG low-temperature hose, and the other end of the floating type transfer barge platform is connected with an LNG transport ship through the LNG non-heat-insulation hose. The method has the advantage of reducing the influence of relative motion between the LNG transport ship and an onshore LNG station or FLNG when the FLNG is in butt joint with the LNG transport ship. The method for transporting LNG has the characteristics of low investment, short construction period and flexibility, and also solves the problem that the berth of the traditional LNG wharf occupies shore resources.

Description

LNG low-temperature floating type conveying system and method

Technical Field

The invention relates to a device and a method for realizing unloading of LNG (liquefied Natural Gas) ship-to-ship or ship-to-LNG receiving facilities by an LNG low-temperature floating type conveying system, and belongs to the technical field of Liquefied Natural Gas (LNG) conveying.

Background

The south China sea has oil and gas resources with oil equivalent of more than 1000 hundred million tons, wherein the natural gas resources account for 83 percent, 70 percent of the natural gas resources come from deep water areas 500 kilometers away from continents of China, and how to economically and effectively develop the natural gas resources in the deep and far sea of the south China sea becomes one of the focuses of attention.

The LNG receiving terminal may be divided into a terrestrial receiving terminal and a marine receiving terminal. Terrestrial receiving terminals are now widely used worldwide and are still rapidly growing with increasing demand for natural gas. The offshore LNG receiving terminal is a new receiving terminal type proposed in recent years, and engineering examples are now available in the world. The offshore LNG receiving terminal may be further divided into a floating receiving terminal and a fixed receiving terminal, wherein the fixed receiving terminal is similar to the terrestrial receiving terminal. According to different LNG receiving terminal forms, the adopted LNG unloading modes are different.

A Floating Production Storage and offloading Unit (FLNG) is a Floating Production device for offshore Natural Gas field development, which is positioned at sea by a mooring system, has functions of exploiting, processing, liquefying, storing, and offloading Natural Gas, and realizes the exploitation and Natural Gas transportation of an offshore Natural Gas field by being used in combination with a Liquefied Natural Gas (LNG) ship. The development of the offshore gas field by using the FLNG ends the single mode that the offshore gas field can only be transported to the shore by adopting a pipeline, saves the transportation cost and does not occupy land space. In addition, the FLNG can be used for the second time after the exploitation of the gas field is finished and is arranged in other natural gas fields, so that the economic performance is higher.

Aiming at the severe sea condition conditions of south China sea, the existing mooring technology is difficult to effectively solve the problem of differential motion between an FLNG floating platform and a carrier of a transport ship, and a specially designed low-temperature unloading system is required to meet the severe requirements of low temperature and shaking working conditions. The low temperature hose conveying system synthesizes the advantage in aspects such as weight, pliability, corrosion resistance, heat-proof quality obvious, when FLNG exports the operation, the effective mode of going is to adopt the cluster to lean on the mooring, be connected with the LNG carrier through mooring cable promptly, and use low temperature hose connection FLNG and LNG carrier to unload, transmit the LNG of FLNG storage to the carrier, consequently require the low temperature hose can bear the ultra-low temperature operating mode in, still need overcome the influence of relative motion between FLNG and the LNG carrier.

In addition, more than 20 LNG receiving stations are built at home on the coast, and more than ten LNG receiving stations are built or planned and built. At present, the main LNG projects are all constructed on berthing wharfs of 1-2 LNG transport ships, and limited shoreline resources are occupied. The shore line available for LNG site construction along the sea is very tight, and the quay line of a newly built LNG project is difficult to approve. In addition, for the LNG project along the inland river bank, the change of the water level of the river channel in the dry season and the rich season is large, the LNG wharf which is normally parked needs to be built in a deep water area, a long trestle extends out of the land area to a wharf area, the investment is high, and channel resources are probably occupied. And the water level difference is large, the ship-alongside facility also presents a great challenge. Therefore, the technology provides a novel LNG floating type conveying system and a novel LNG floating type conveying method, and an LNG berthing wharf does not need to be built. The LNG transport ship is anchored in a project peripheral water area near the shore, the loading and unloading operation of LNG can be realized through the movable floating type transfer and docking platform 1 and the hose provided with the quick connection and emergency separation system, and the LNG transport ship can replace the traditional transportation mode of an LNG wharf and a trestle.

Disclosure of Invention

In view of the above problems, an object of the present invention is to provide a system and a method for low-temperature floating transfer of LNG, so as to solve the problem that when an FLNG is docked with an LNG carrier, the influence of relative motion between the FLNG and the LNG carrier is caused, and when the LNG carrier is docked with a land, a dedicated LNG terminal and a trestle are required, thereby occupying shoreline resources.

In order to achieve the purpose, the invention adopts the following technical scheme:

in one aspect, the invention provides an LNG low-temperature floating type conveying system, which comprises a floating transfer barge platform, an LNG low-temperature floating hose and an LNG non-heat-insulation hose, wherein one end of the floating transfer barge platform is connected with a pipe orifice fixed on the land or on an LNG loading ship through the LNG low-temperature hose, and the other end of the floating transfer barge platform is connected with an LNG transport ship through the LNG non-heat-insulation hose.

Preferably, the system further comprises a quick connection/disconnection system, one end of the LNG non-insulation hose is connected with the floating transfer barge, and the other end of the LNG non-insulation hose is connected with the LNG transport ship through the quick connection/disconnection system.

Preferably, the floating transfer barge platform is further provided with a first saddle and the emergency release system, one end of the LNG low-temperature floating hose is connected with the pipe orifice fixed on the land or on the LNG loading vessel, and the other end of the LNG low-temperature floating hose bypasses the first saddle and is connected with the emergency release system.

Preferably, the LNG low-temperature floating device further comprises a second saddle and a hose retracting device fixed on land or an LNG charging ship, one end of the LNG low-temperature floating hose bypasses the second saddle and the hose retracting device and then is connected with the pipe opening, and the hose retracting device is used for retracting the LNG low-temperature floating hose.

Preferably, the hose winding and unwinding device is a roller.

Preferably, the system further comprises a vacuum mooring system for fast mooring with the LNG carrier.

Preferably, the floating transfer barge platform is further provided with a falling prevention system for preventing the LNG low-temperature floating hose from falling.

Preferably, the LNG low-temperature floating hose sequentially comprises a sealing layer, an armor layer, a cold insulation layer, a leakage monitoring layer and an outer protective layer from inside to outside.

Preferably, the leakage monitoring layer is a temperature sensing optical fiber wound outside the cold insulation layer and used for monitoring leakage of the LNG.

In another aspect, the present invention further provides a LNG cryogenic floating transfer system, which includes:

in an initial state, the floating transfer connection platform floats on the shore, and the LNG low-temperature floating hose is connected with a hose opening fixed on the land FLNG through the LNG low-temperature hose;

the LNG transport ship finishes mooring after arriving in a specified water area range, and the floating transfer and connection platform is driven out from the bank through a tugboat or a self-powered device to drive the LNG low-temperature floating hose to the LNG transport ship;

after the floating transfer and docking platform reaches the periphery of the LNG transport ship, the floating transfer and docking platform is docked with the LNG transport ship through a vacuum mooring system, and then the LNG non-heat-insulation hose is hoisted and connected with a discharge manifold of the LNG transport ship;

the LNG transport ship starts the unloading pump, and LNG passes through the floating type transfer barge platform along the LNG non-heat-insulation hose through the quick connection/disconnection system and finally enters the pipe orifice through the LNG low-temperature floating hose to realize floating type transfer barge.

Due to the adoption of the technical scheme, the invention has the following advantages:

1. the method is suitable for the overwater transmission of the low-temperature LNG, and comprises ship-to-ship transmission and ship-to-shore transmission.

2. The floating movable transfer barge platform is connected with an LNG transport ship, LNG is loaded and unloaded in a LNG low-temperature hose conveying mode, the transfer barge platform is moved and fixed on the LNG transport ship in a docking mode, docking of the LNG transport ship is achieved, and relative motion between the ship and an onshore facility is compensated through flexible connection of the LNG low-temperature hose.

3. The method has the advantages of good compatibility to shore, no occupation of shore line resources, quick construction, low investment, high sledding degree, small occupied area of water and the like.

Drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the invention. Like reference numerals refer to like parts throughout the drawings. In the drawings:

fig. 1 is a schematic structural diagram of an LNG cryogenic floating transfer system provided by the present invention;

FIG. 2 is a sectional view of an LNG cryogenic floating hose

The reference symbols in the drawings denote the following:

the system comprises a 1-floating transfer platform, a 2-LNG low-temperature floating hose, a 3-LNG non-heat-insulation hose, a 4-first saddle, a 5-second saddle, a 6-hose take-up and pay-off device, a 7-vacuum mooring system, an 8-quick connection/disconnection system, a 9-LNG transport ship, a 10-land or FLNG, a 21-sealing layer, a 22-armor layer, a 23-cold insulation layer, a 24-leakage monitoring layer and a 25-outer protective layer.

Detailed Description

Exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the invention are shown in the drawings, it should be understood that the invention can be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

The embodiment of the invention provides an LNG low-temperature floating type conveying system and method, which are suitable for the water transmission of low-temperature LNG, including ship-to-ship transmission and ship-to-shore transmission. The floating movable transfer barge platform is connected with the LNG carrier 9, LNG is loaded and unloaded in a mode of LNG low-temperature hose conveying, the transfer barge platform moves and is anchored and fixed on the LNG carrier 9 to realize the butt joint of the LNG carrier 9, and the relative motion of the LNG carrier and the onshore facility is compensated through the flexible connection of the LNG low-temperature hose. The LNG loading and unloading device can adapt to large water level difference change and can realize LNG loading and unloading operation under different water levels. The method has the advantages of good compatibility to shore, no occupation of shore line resources, quick construction, low investment, high sledding degree, small occupied area of water and the like.

The LNG low-temperature floating type conveying system comprises a floating transfer barge platform 1, an LNG low-temperature floating hose 2 and an LNG non-heat-insulation hose 3, wherein one end of the floating transfer barge platform 1 is connected with a pipe orifice fixed on land 10 or an LNG loading ship through the LNG low-temperature hose, and the other end of the floating transfer barge platform 1 is connected with an LNG transport ship 9 through the LNG non-heat-insulation hose 3.

In use, when the transfer device is used for transferring LNG on the LNG carrier 9 to the land 10, one end of the floating transfer platform 1 is connected to a pipe orifice fixed to the land 10 through the LNG cryogenic hose, and the other end of the floating transfer platform is connected to the LNG carrier 9 through the LNG non-insulated hose 3. And starting valves, and finally delivering the LNG to land 10 by sequentially flowing the LNG through the LNG transport ship 9, the LNG non-heat-insulation hose 3, the floating transfer platform 1 and the LNG low-temperature floating hose 2.

When the floating transfer platform is used for transporting LNG on the FLNG to the LNG transport ship 9 for transportation, one end of the floating transfer platform 1 is connected with a pipe orifice fixed on the FLNG through the LNG low-temperature hose, and the other end of the floating transfer platform is connected with the LNG transport ship 9 through the LNG non-thermal-insulation hose 3. Starting valves, LNG flows through the LNG low-temperature floating hose 2, the floating transfer barge 1, the LNG non-insulated hose 3 and the LNG carrier 9 in sequence and is finally conveyed to the LNG carrier 9, and then the LNG is conveyed to land 10 through the LNG carrier 9.

The floating movable transfer barge platform is connected with the LNG carrier 9, LNG is loaded and unloaded in a mode of LNG low-temperature hose conveying, the transfer barge platform moves and is anchored and fixed on the LNG carrier 9 to realize the butt joint of the LNG carrier 9, and the relative motion of the LNG carrier and the onshore facility is compensated through the flexible connection of the LNG low-temperature hose. In addition, compare and need construct the LNG receiving station among the prior art, can reduce the occupation of bank line resource.

Further, the LNG low-temperature floating transportation system further comprises a quick connection/disconnection system (QCDC)8, wherein one end of the LNG non-insulated hose 3 is connected with the floating transfer barge 1, and the other end of the LNG non-insulated hose is connected with the LNG carrier 9 through the quick connection/disconnection system 8. The quick connection and disconnection with the loading and unloading manifold of the transport ship in the motion state can be realized.

The floating transfer barge platform 1 is also provided with a first saddle 4 and the emergency separation system, one end of the LNG low-temperature floating hose 2 is connected with a pipe orifice fixed on the land 10 or on the LNG loading ship, and the other end of the LNG low-temperature floating hose bypasses the first saddle 4 to be connected with the emergency separation system. The emergency separation system can monitor the relative position relation between the platform position and the shore and between the platform position and the LNG transport ship 9, and can realize the emergency cut-off and separation functions when a fault or a deviation position occurs;

the LNG low-temperature floating conveying system further comprises a second saddle 5 and a hose winding and unwinding device 6 fixed on land 10 or an LNG loading ship, one end of the LNG low-temperature floating hose 2 bypasses the second saddle 5 and the hose winding and unwinding device 6 and then is connected with the pipe opening, and the hose winding and unwinding device 6 is used for winding and unwinding the LNG low-temperature floating hose 2.

The first saddle 4 and the second saddle 5 are arranged at the joint of the LNG low-temperature floating hose 2 and the shore or the transfer barge platform, so that the rubbing with peripheral structures is avoided, and the stress condition of the hose is improved.

The winding and unwinding device is designed to realize the winding and unwinding of the LNG non-heat-insulation hose 3, the LNG low-temperature hose can retract or release the transmission system through the onshore 10 hose unwinding and unwinding device 6 such as a roller, and the hose can be wound and recovered through the roller, so that the floor area is reduced;

the LNG cryogenic floating transfer system further comprises a vacuum mooring system 7 for fast mooring to the LNG carrier 9. The floating transfer platform 1 is moored with the LNG carrier 9 using a vacuum mooring system 7 so that a1 floats with the LNGC.

And the floating transfer barge platform 1 is also provided with a falling prevention system for preventing the LNG low-temperature floating hose 2 from falling. The anti-falling system is a set of hydraulic damping system, is arranged in front of the ERS and is connected with the LNG low-temperature floating hose 2 through a steel wire rope, and after the ERS is separated, the LNG low-temperature floating hose 2 and the platform connecting end slowly fall off along the second saddle 5 and enter water through a hydraulic mechanism, so that the rapid falling is prevented from causing damage to people and a transfer platform.

As shown in fig. 2, the LNG cryogenic floating hose 2 includes a sealing layer 21, an armor layer 22, a cold insulation layer 23, a leakage monitoring layer 24 and an outer protection layer 25 in sequence from inside to outside. Sealing layer 21 is used for sealed low temperature medium and bears the weight of the internal pressure of hose 2 for LNG realizes mobile the transport in the sealing layer is inside, armor 22 is used for reinforcing hose axial tensile resistance, guarantees hose 2's stress intensity, cold insulation layer 23 is used for providing low temperature medium cold insulation, reduces the cold loss, prevents that phenomena such as frost icing from appearing in low temperature hose 2 outside, leakage monitoring layer 24 is used for carrying out state monitoring to low temperature hose 2 operation process, can in time discover and take effective safeguard measure when low temperature medium leaks appearing, outer inoxidizing coating 25 is used for protecting low temperature hose 2, and can dampproofing keep apart, prevents that outside steam from permeating inside the hose. All functional layer materials of the low-temperature hose are flexible materials resistant to ultralow temperature, so that the low-temperature hose can be ensured to have large operation elasticity, the low-temperature hose can be curled, folded and released in the operation process, and the low-temperature hose is convenient to store and transport.

The leakage monitoring layer is a temperature sensing optical fiber wound outside the cold insulation layer and used for monitoring leakage of the LNG. The leakage monitoring system is arranged in the hose in a temperature sensing optical fiber winding mode, has the function of monitoring low-temperature LNG leakage, can trigger an alarm signal if leakage occurs, and can realize leakage position judgment;

the LNG low-temperature hose can float on the water surface integrally, and the heat insulation material is wrapped outside the LNG low-temperature hose, so that the LNG low-temperature hose cannot freeze due to heat leakage outside the LNG low-temperature hose in the transmission process.

Another embodiment of the present invention further provides a LNG cryogenic floating transfer system, comprising:

1) in an initial state, the floating transfer connection platform 1 floats on the shore, and the LNG low-temperature floating hose 2 is connected with a pipe orifice fixed on the land 10 or an LNG loading ship through the LNG low-temperature floating hose 2;

2) after the LNG carrier 9 arrives in the range of the designated water area, the floating transfer barge platform 1A1 is driven out from the shore by a tugboat or a self-powered device to drive the LNG low-temperature floating hose 2 to the LNG carrier 9;

3) after the floating transfer and docking platform 1 reaches the periphery of the LNG transport ship 9, the floating transfer and docking platform is docked with the LNG transport ship 9 through a vacuum mooring system 7, then a hose is hoisted, and the hose is connected with a discharge manifold of the LNG transport ship 9;

4) the LNG transport ship 9 starts the unloading pump, LNG passes through the floating transfer platform 1 along the LNG non-heat-insulation hose 3 through the quick connection/disconnection system 8, and finally enters the pipe orifice through the LNG low-temperature floating hose 2, so that floating transfer is realized.

The floating transfer barge platform 1 is adopted, and a hydraulic structure is not fixed, so that shoreline resources are not occupied; the LNG low-temperature hose is adopted to transmit LNG, a solution which is suitable for large water level difference change is provided, LNG loading and unloading operation under different water levels can be realized, the LNG low-temperature hose can be rolled, folded and unfolded, the whole occupied area is small, and the LNG low-temperature hose is convenient to move; the floating transfer barge platform 1 can realize berthing and connection of 9 types of LNG transport ships with different sizes, and avoids the compatibility limitation of LNG receiving and unloading wharf size and mooring facilities on the ship types; the floating LNG hose with the heat-insulating layer structure is adopted, so that icing in the water surface operation process is prevented, and the safety of unloading operation is enhanced; the transfer barge platform is provided with a power device, can be flexibly operated and is in berth with the LNG transport ship 9; the invention is provided with a leakage monitoring system, a pressure safety valve and a fire combustible gas detection facility, thereby ensuring the operation safety of the platform; the emergency separation system comprises an emergency separation system and an emergency cut-off valve, and can ensure safe separation under the working condition of an accident; compared with the traditional LNG wharf, the construction period is short, and the investment is low.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.

Claims (10)

1. The LNG low-temperature floating type conveying system is characterized by comprising a floating transfer barge platform, an LNG low-temperature floating hose and an LNG non-heat-insulation hose, wherein one end of the floating transfer barge platform is connected with a pipe orifice fixed on the land or on an LNG loading ship through the LNG low-temperature hose, and the other end of the floating transfer barge platform is connected with an LNG transport ship through the LNG non-heat-insulation hose.

2. The LNG cryogenic floating transfer system of claim 1, further comprising a quick connect/disconnect system, wherein one end of the LNG non-insulated hose is connected to the floating transfer barge, and the other end of the LNG non-insulated hose is connected to the LNG carrier via the quick connect/disconnect system.

3. The LNG cryogenic floating transfer system of claim 1, wherein the floating transfer barge further has a first saddle and the emergency release system mounted thereon, and the LNG cryogenic floating hose is connected to the pipe orifice fixed on land or on an LNG loading vessel at one end thereof and to the emergency release system at the other end thereof by bypassing the first saddle.

4. The LNG cryogenic floating transfer system of claim 3, further comprising a second saddle and a hose reel fixed to an onshore or LNG loading vessel, wherein one end of the LNG cryogenic floating hose is connected to the nozzle after bypassing the second saddle and the hose reel, and the hose reel is used for reeling the LNG cryogenic floating hose.

5. LNG cryogenic floating transfer system according to claim 4, characterized in that the hose reel is a drum.

6. The LNG cryogenic floating transfer system of claim 5, further comprising a vacuum mooring system for rapid mooring to the LNG carrier.

7. The LNG low temperature floating transfer system of claim 6, wherein the floating transfer barge further has a fall prevention system mounted thereon for preventing the LNG low temperature floating hose from falling.

8. The LNG cryogenic floating transfer system of claim 1, wherein the LNG cryogenic floating hose comprises, in order from the inside to the outside, a sealing layer, an armor layer, a cold insulation layer, a leakage monitoring layer and an outer shielding layer.

9. The LNG cryogenic floating transfer system of claim 8, wherein the leakage monitoring layer is a temperature sensitive optical fiber wound outside the cold insulation layer for monitoring leakage of the LNG.

10. An LNG cryogenic floating transfer method, based on the LNG cryogenic floating transfer system of any one of claims 1 to 9, comprising the steps of:

in an initial state, the floating transfer connection platform floats on the shore, and the LNG low-temperature floating hose is connected with a hose opening fixed on the land FLNG through the LNG low-temperature hose;

the LNG transport ship finishes mooring after arriving in a specified water area range, and the floating transfer and connection platform is driven out from the bank through a tugboat or a self-powered device to drive the LNG low-temperature floating hose to the LNG transport ship;

after the floating transfer and docking platform reaches the periphery of the LNG transport ship, the floating transfer and docking platform is docked with the LNG transport ship through a vacuum mooring system, and then the LNG non-heat-insulation hose is hoisted and connected with a discharge manifold of the LNG transport ship;

the LNG transport ship starts the unloading pump, and LNG passes through the floating type transfer barge platform along the LNG non-heat-insulation hose through the quick connection/disconnection system and finally enters the pipe orifice through the LNG low-temperature floating hose to realize floating type transfer barge.

Images