LNG (Liquefied Natural Gas) ship fire extinguishing system and LNG ship

Abstract

The invention relates to the technical field of fire-fighting equipment, in particular to an LNG ship fire-fighting system and an LNG ship. An LNG ship fire-fighting system comprises a water inlet used for making contact with seawater, the water inlet is connected with an emergency fire-fighting pipeline and a foam fire-fighting pipeline, the emergency fire-fighting pipeline is provided with an emergency fire-fighting pump, and the foam fire-fighting pipeline is provided with a foam seawater pump. A second isolating valve is arranged on the emergency fire-fighting pipeline and located on the upstream of the emergency fire-fighting pump, a first isolating valve is arranged on the foam fire-fighting pipeline and located on the upstream of the foam sea water pump, the discharge capacity of the emergency fire-fighting pump is smaller than that of the foam sea water pump, and the maximum discharge pressure of the emergency fire-fighting pump is lower than that of the foam sea water pump. The emergency fire-fighting pipeline and the foam fire-fighting pipeline are mutually independent, so that the problems that in the prior art, an emergency fire-fighting system and a foam fire-fighting system adopt the same pump to pump seawater, and the foam fire-fighting system needs a large amount of water, so that the pressure is too high when the emergency fire-fighting system is used, and sailors are difficult to control are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of fire-fighting facilities, and in particular to a fire-fighting system for an LNG ship and an LNG ship. Background Art

[0002] Liquefied natural gas carriers ("LNG carriers" for short) refer to "ships" that are specifically used to transport liquefied natural gas. During the transportation process, safety must be an issue that must be considered. LNG carriers may leak, posing a risk of fire, so fire-fighting systems must be installed on LNG carriers. For LNG carriers, once a leak occurs, the leaked gas will quickly vaporize and mix with the air to form a flammable gas cloud, which will cause a fire or explosion when encountering a fire source. In view of this feature of LNG carriers, foam fire-fighting systems are usually installed on the ships. The IGC Rules (International Code for the Construction and Equipment of Ships Carrying Liquefied Gases in Bulk) and the SOLAS Convention require that LNG carriers must be equipped with fixed foam fire-fighting systems to ensure rapid response to sudden fire conditions. The foam fire-fighting system must cover the engine room area, decks and sides that may be affected by the leak.

[0003] For LNG carriers, the main equipment in the foam firefighting system is typically integrated into a single compartment, the foam room, located on the ship's main deck. Foam liquid and seawater are mixed in a specific ratio in the foam room and then piped to the ship's engine room for firefighting. The foam liquid is pre-loaded in the foam room's storage tanks, while seawater is pumped from the local sea area to the foam room based on immediate firefighting needs.

[0004] The common method for supplying seawater is through an emergency fire pump located in the bow pump room. Conventional emergency fire pumps provide both emergency firefighting and foam firefighting seawater. However, the total amount of seawater required for emergency firefighting is relatively small, while the total amount of seawater required for foam firefighting is approximately nine times that of emergency firefighting. This results in higher specifications for the emergency fire pump, leading to higher discharge pressures during emergency firefighting operations, making it difficult for crew members to operate, thus affecting the ship's normal emergency firefighting operations. This is unacceptable for ensuring the safety and reliability of the LNG carrier during navigation, as well as the personal safety of the crew. Summary of the Invention

[0005] In view of this, the present invention provides an LNG ship fire-fighting system, which is used to solve the problem in the prior art that the emergency fire-fighting system and the foam fire-fighting system use the same pump to extract seawater, and the foam fire-fighting system requires a large amount of water, resulting in excessive pressure when the emergency fire-fighting system is in use, making it difficult for the crew to operate; the present invention also provides an LNG ship for solving the above-mentioned technical problems.

[0006] An LNG ship fire-fighting system includes a water inlet for contact with seawater, wherein the water inlet is respectively connected to an emergency fire-fighting pipeline and a foam fire-fighting pipeline, the emergency fire-fighting pipeline is provided with an emergency fire-fighting pump, and the foam fire-fighting pipeline is provided with a foam seawater pump. A second isolation valve for controlling the connection between the water inlet and the emergency fire-fighting pump is provided upstream of the emergency fire-fighting pump on the emergency fire-fighting pipeline, and a first isolation valve for controlling the connection between the water inlet and the foam seawater pump is provided upstream of the foam seawater pump on the foam fire-fighting pipeline. The displacement of the emergency fire-fighting pump is smaller than that of the foam seawater pump, and the maximum discharge pressure of the emergency fire-fighting pump is lower than that of the foam seawater pump.

[0007] Furthermore, a connecting pipe connecting the foam fire fighting pipeline and the emergency fire fighting pipeline is provided downstream of the foam seawater pump of the foam fire fighting pipeline and downstream of the emergency fire fighting pump, and a third isolation valve for controlling on-off is provided on the connecting pipe.

[0008] Furthermore, a fourth isolation valve is provided between the third isolation valve and the emergency fire pump.

[0009] Furthermore, the water inlet is an emergency seabed door located below the sea surface during driving.

[0010] Furthermore, the first isolation valve, the second isolation valve, the third isolation valve and the fourth isolation valve are all wafer-type double-eccentric butterfly valves.

[0011] The beneficial effects of the LNG ship fire fighting system in the present invention are as follows: in the present invention, by arranging a water inlet, it is convenient to obtain seawater for the fire fighting system, and by connecting the emergency fire fighting pipeline and the foam fire fighting pipeline respectively on the water inlet, it is convenient to play the role of emergency fire fighting and foam fire fighting respectively; by arranging an emergency fire fighting pump on the emergency fire fighting pipeline and arranging a foam seawater pump on the foam fire fighting pipeline, water can be supplied to the emergency fire fighting pipeline and the foam fire fighting pipeline respectively, thereby facilitating the independent operation of the two groups of fire fighting pipelines; by arranging the first isolation valve and the second isolation valve, the emergency fire fighting pipeline and the foam fire fighting pipeline are made independent of each other. Since the working scenes and demand conditions of the two are inconsistent, the independent arrangement of the two facilitates the independent function of each other The foam fire pump has a large volume of water, and the emergency fire pump has a large volume of water, so the emergency fire pump has a small volume of water, and the maximum discharge pressure of the emergency fire pump is lower than that of the foam seawater pump, which can meet their respective needs. At the same time, since the emergency fire pipeline no longer passes through the water of the foam seawater pump, the emergency fire pipeline does not need to pass through water with excessive pressure, which is conducive to reducing the difficulty of manufacturing the emergency fire pipeline, thereby solving the problem in the prior art that the emergency fire system and the foam fire system use the same pump to extract seawater, and the foam fire system has a large water demand, resulting in excessive pressure when the emergency fire system is used, making it difficult for the crew to operate.

[0012] An LNG ship comprises a fire-fighting system arranged on the hull, wherein the system comprises a water inlet for contact with seawater, the water inlet being respectively connected to an emergency fire-fighting pipeline and a foam fire-fighting pipeline, the emergency fire-fighting pipeline being provided with an emergency fire-fighting pump, the foam fire-fighting pipeline being provided with a foam seawater pump, the emergency fire-fighting pipeline being provided with a second isolating valve for controlling the connection between the water inlet and the emergency fire-fighting pump, located upstream of the emergency fire-fighting pump, the foam fire-fighting pipeline being provided with a first isolating valve for controlling the connection between the water inlet and the foam seawater pump, the displacement of the emergency fire-fighting pump being smaller than that of the foam seawater pump, the maximum discharge pressure of the emergency fire-fighting pump being lower than that of the foam seawater pump, and the water inlet being provided on the outer peripheral surface of the LNG ship below the sea surface.

[0013] Furthermore, a connecting pipe connecting the foam fire fighting pipeline and the emergency fire fighting pipeline is provided downstream of the foam seawater pump of the foam fire fighting pipeline and downstream of the emergency fire fighting pump, and a third isolation valve for controlling on-off is provided on the connecting pipe.

[0014] Furthermore, a fourth isolation valve is provided between the third isolation valve and the emergency fire pump.

[0015] Furthermore, the water inlet is an emergency seabed door located below the sea surface during driving.

[0016] Furthermore, the first isolation valve, the second isolation valve, the third isolation valve and the fourth isolation valve are all wafer-type double-eccentric butterfly valves.

[0017] The beneficial effects of the LNG ship in the present invention are as follows: the present invention facilitates the acquisition of seawater for the fire-fighting system by arranging a water inlet, and facilitates the functions of emergency fire-fighting and foam fire-fighting respectively by connecting the emergency fire-fighting pipeline and the foam fire-fighting pipeline to the water inlet; by arranging an emergency fire-fighting pump on the emergency fire-fighting pipeline and a foam seawater pump on the foam fire-fighting pipeline, water can be supplied to the emergency fire-fighting pipeline and the foam fire-fighting pipeline respectively, thereby facilitating the independent operation of the two groups of fire-fighting pipelines; by arranging the first isolation valve and the second isolation valve, the emergency fire-fighting pipeline and the foam fire-fighting pipeline are made independent of each other. Since the working scenarios and demand conditions of the two are inconsistent, the independent arrangement of the two facilitates the independence of their respective functions. Moreover, by setting up the same water inlet, it is convenient to reduce the structure on the hull and facilitate the layout; since the amount of water required by the foam fire pump is much greater than that of the emergency fire pump, the displacement of the emergency fire pump is smaller than that of the foam seawater pump, and the maximum discharge pressure of the emergency fire pump is lower than that of the foam seawater pump, which can meet their respective needs. At the same time, since the emergency fire pipeline no longer passes through the water of the foam seawater pump, the emergency fire pipeline does not have to pass through water with excessive pressure, which is conducive to reducing the manufacturing difficulty of the emergency fire pipeline, and thus solves the problem in the prior art that the emergency fire system and the foam fire system use the same pump to extract seawater, and the foam fire system requires a large amount of water, resulting in excessive pressure when the emergency fire system is used, making it difficult for the crew to operate. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0019] Figure 1 It is a structural diagram of the fire-fighting system of the LNG ship in the present invention.

[0020] The meanings of the numbers in the figure are: 11, foam room; 12, emergency fire-fighting target user; 13, emergency seabed door; 21, foam seawater pump; 22, emergency fire-fighting pump; 31, first isolation valve; 32, second isolation valve; 33, third isolation valve; 34, fourth isolation valve; 41, connecting pipe; 42, main pipeline. DETAILED DESCRIPTION

[0021] To make the objectives, technical solutions, and advantages of the present invention more clearly apparent, the present invention is described below using specific embodiments shown in the accompanying drawings. However, it should be understood that these descriptions are merely illustrative and are not intended to limit the scope of the present invention. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessary confusion of the concepts of the present invention.

[0022] The terms used in this disclosure are for the purpose of describing specific embodiments only and are not intended to limit the disclosure. As used in this disclosure and the appended claims, the singular forms "a," "an," "the," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term "and / or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

[0023] It should be understood that although the terms first, second, third, etc. may be used in this disclosure to describe various information, such information should not be limited to these terms and should not be understood to indicate or imply relative importance. These terms are only used to distinguish information of the same type from each other. For example, first information may also be referred to as second information, and similarly, second information may also be referred to as first information without departing from the scope of this disclosure. Depending on the context, the word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining."

[0024] In the description of the present invention, it should be understood that the terms "longitudinal", "transverse", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention.

[0025] In the description of the present invention, unless otherwise specified and limited, it should be noted that the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it can be a mechanical connection or an electrical connection, or it can be the internal communication between two components. It can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to the specific circumstances.

[0026] In the following description, the suffixes such as "module", "component" or "unit" used to represent elements are only used to facilitate the description of the present invention and have no specific meaning. Therefore, "module" and "component" can be used interchangeably.

[0027] In order to better understand the technical solution of the present invention, the present invention is described in detail below with reference to the accompanying drawings.

[0028] In the embodiment of the LNG ship fire fighting system of the present invention:

[0029] During the use of ships, especially LNG ships, general fires and fires caused by LNG leakage may occur. Different fire extinguishing methods are required for different types of fires. For general fires, emergency firefighting using water as the fire extinguishing medium can be started. For LNG leakage, foam firefighting is required. Therefore, if Figure 1 As shown, the firefighting system of an LNG carrier in this embodiment includes emergency firefighting lines and foam firefighting lines. Specifically, a water inlet is provided on the LNG carrier's hull. This inlet is located below the sea surface when the ship is underway, allowing for easy access to seawater for distribution to the emergency and foam firefighting lines. In this embodiment, the water inlet is an emergency submarine door 13. Behind this door 13 is a main pipeline 42 leading to the emergency and foam firefighting lines. This allows only one emergency submarine door 13 to be installed, reducing the number of emergency submarine doors 13 installed on the hull and simplifying the manufacturing process.

[0030] At the ends of the main pipeline 42, an emergency firefighting pipeline and a foam firefighting pipeline are connected, respectively. An emergency firefighting pump 22 is provided on the emergency firefighting pipeline, and a foam seawater pump 21 is provided on the foam firefighting pipeline. The emergency firefighting pump 22 can pump seawater from the emergency seabed gate 13 to the emergency firefighting pipeline, and the foam seawater pump 21 can pump seawater from the emergency seabed gate 13 to the foam firefighting pipeline. Since the two firefighting pipelines generally do not operate at the same time, they need to be able to operate separately. A second isolation valve 32 is provided upstream of the emergency firefighting pump 22 on the emergency firefighting pipeline for controlling the connection between the water inlet and the emergency firefighting pump 22. A first isolation valve 31 is provided upstream of the foam seawater pump 21 on the foam firefighting pipeline for controlling the connection between the water inlet and the foam seawater pump 21. Consequently, under the action of the first isolation valve 31 and the second isolation valve 32, seawater can flow separately to the foam firefighting pipeline or the emergency firefighting pipeline. Of course, if special circumstances arise and it is necessary to supply water to both the foam firefighting pipeline and the emergency firefighting pipeline at the same time, the first isolation valve 31 and the second isolation valve 32 can also be opened simultaneously.

[0031] Since the amount of water required in the foam fire-fighting pipeline is much greater than the amount of water required in the emergency fire-fighting pipeline, the corresponding emergency fire-fighting pump 22 has a smaller displacement than the foam seawater pump 21, and the maximum discharge pressure of the emergency fire-fighting pump 22 is lower than that of the foam seawater pump 21. During use, the pressure in the emergency fire-fighting pipeline is brought by the emergency fire-fighting pump 22, so the pipeline pressure in the emergency fire-fighting pipeline can be made lower than the pressure in the foam fire-fighting pipeline. Therefore, during the manufacturing process, the design pressure in the emergency fire-fighting pipeline is comprehensively reduced, which saves pipeline production costs and material procurement costs while also greatly reducing the risk of pipeline leakage caused by excessive discharge pressure of the emergency fire-fighting pump 22.

[0032] To ensure proper firefighting, an emergency firefighting target user 12 is located at the end of the emergency firefighting pipeline. Seawater is supplied to the emergency firefighting target user 12 to achieve firefighting. A foam room 11 is located at the end of the foam firefighting pipeline. A tank for storing foam liquid is located within the foam room 11. When seawater mixes with the foam liquid in the tank, foam is generated for firefighting.

[0033] The emergency fire pump 22 may require maintenance during the vessel's voyage. In this embodiment, two pumps are actually installed on the vessel. Therefore, the foam seawater pump 21 can temporarily replace the emergency fire pump 22 during maintenance. In this embodiment, a connecting pipe 41 is provided downstream of the foam seawater pump 21 on the foam fire line and downstream of the emergency fire pump 22 on the emergency fire line. This connecting pipe 41 is equipped with a third isolation valve 33 for on / off control. Seawater pumped by the seawater foam pump can be delivered to the emergency fire line through the third isolation valve 33, temporarily providing water to the emergency fire line. This prevents the emergency fire line from being unavailable due to a fire while the emergency fire pump 22 is being repaired. Of course, it is worth noting that the connecting pipe 41 is located upstream of the foam room 11, allowing seawater to flow into the emergency fire line before it passes through the foam room 11.

[0034] To prevent seawater from entering the emergency fire pump 22 or flowing out through the gap in the emergency fire pump 22 during maintenance, a fourth isolation valve 34 is provided between the third isolation valve 33 and the emergency fire pump 22. Closing the fourth isolation valve 34 while the third isolation valve 33 is open prevents seawater from flowing back. It is worth noting that the first isolation valve 31, the second isolation valve 32, the third isolation valve 33, and the fourth isolation valve 34 in this embodiment are all wafer-type double-eccentric butterfly valves.

[0035] In the embodiment of the LNG carrier of the present invention,

[0036] The LNG carrier in this embodiment includes a firefighting system mounted on the hull. This firefighting system is structurally identical to the firefighting system of the aforementioned LNG carrier and will not be repeated here. It is noteworthy that the water inlet of this firefighting system is located on the outer circumference of the LNG carrier, located below the sea surface. The remaining structure of the LNG carrier is identical to that of conventional LNG carriers and will not be further described here.

[0037] It should be understood that the embodiments described are only a portion of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

Claims

1. An LNG ship fire fighting system, characterized by: The system includes a water inlet for contact with seawater, the water inlet being connected to an emergency fire-fighting pipeline and a foam fire-fighting pipeline respectively, an emergency fire-fighting pump being provided on the emergency fire-fighting pipeline, and a foam seawater pump being provided on the foam fire-fighting pipeline, a second isolation valve for controlling the connection between the water inlet and the emergency fire-fighting pump being provided upstream of the emergency fire-fighting pump on the emergency fire-fighting pipeline, and a first isolation valve for controlling the connection between the water inlet and the foam seawater pump being provided upstream of the foam seawater pump on the foam fire-fighting pipeline, the displacement of the emergency fire-fighting pump being smaller than that of the foam seawater pump, and the maximum discharge pressure of the emergency fire-fighting pump being lower than that of the foam seawater pump.

2. The LNG ship fire fighting system according to claim 1, characterized in that: A connecting pipe connecting the foam fire fighting pipeline and the emergency fire fighting pipeline is further provided downstream of the foam seawater pump of the foam fire fighting pipeline and downstream of the emergency fire fighting pump. A third isolation valve for controlling on-off is provided on the connecting pipe.

3. The LNG ship fire fighting system according to claim 2, characterized in that: A fourth isolation valve is also provided between the third isolation valve and the emergency fire pump.

4. The LNG ship fire fighting system according to any one of claims 1 to 3, characterized in that: The water inlet is an emergency seabed door located below the sea surface when the vehicle is traveling.

5. The LNG ship fire fighting system according to claim 4, characterized in that: The first isolation valve, the second isolation valve, the third isolation valve and the fourth isolation valve are all wafer-type double-eccentric butterfly valves.

6. An LNG carrier, comprising a fire-fighting system mounted on the hull, characterized in that: The fire-fighting system is the same as the LNG ship fire-fighting system according to any one of claims 1 to 5, and the water inlet is arranged on the outer peripheral surface of the LNG ship below the sea surface.

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