A marine oil support vessel using ammonia fuel

Abstract

The invention discloses an offshore oil support vessel using ammonia fuel, comprising a main deck, and a bow peak tank, a bow thruster tank, an engine room, an ammonia fuel tank, a steering propeller tank and a stern ballast tank located below the main deck; the bow peak tank, the bow thruster tank, the engine room, the ammonia fuel tank, the steering propeller tank and the stern ballast tank are divided and arranged in sequence from the bow to the stern by watertight transverse bulkheads; ammonia fuel filling stations are arranged on both sides of the main deck; the ammonia fuel filling stations pass through the deck to the ammonia fuel tank; the ammonia fuel tank is connected with the engine room through a transmission pipeline, and ammonia is used as the fuel for the hull power, and a tank for storing ammonia fuel is safely arranged on the hull, thereby successfully using ammonia as the fuel for the hull, greatly improving the environmental protection of the oil support vessel.

Description

Technical Field

[0001] The present invention relates to the field of new energy for ships, and in particular to an offshore oil support vessel using ammonia fuel. Background Art

[0002] The emission restrictions faced by the global shipping industry have become increasingly stringent, and the concepts of green, low-carbon, energy-saving and emission reduction have been widely valued in the field of ship design and construction. The application of clean energy to replace traditional fuels has become a major trend in the development of the industry. According to the goals set by IMO, by 2050, the annual greenhouse gas emissions of the shipping industry will be reduced by more than 50% compared with 2008.

[0003] Offshore oil support vessel (OSV) is a group of ships classified by various functions of offshore oil support missions. Generally speaking, it is mainly divided into: auxiliary work ship (AHTS), supply ship (PSV), stand ship, etc. Its main functions are to provide comprehensive ship operation support services for offshore oil exploration, development, and production, provide anchoring operations in various water depths, towing and positioning of offshore facilities and large engineering ships, transportation and supply of drilling and production materials, oil field protection, oil lifting support, oil field production support, fire fighting and marine pollution treatment and other ship operation services.

[0004] Existing offshore oil support vessels use fuel oil as fuel, but the gases they emit will cause certain pollution to the environment and do not meet emission standards. Therefore, in order to make fuel emissions meet the more stringent emission standards that are currently in force or will soon take effect, it is necessary to use higher quality oil products (such as low-sulfur oil), increase post-processing equipment, etc., or combine the above-mentioned technical means for comprehensive utilization to meet more stringent requirements.

[0005] However, the main dimensions of this type of ship are usually small, with numerous equipment and compact space, making it difficult to arrange the above-mentioned new equipment; in addition, the use of higher-quality oil products will significantly increase fuel costs, and auxiliary equipment such as low-sulfur oil coolers will also need to be added, which reduces pollutant emissions but cannot solve the problem of carbon dioxide emissions.

[0006] It can be seen that how to achieve "zero" emissions of offshore oil support vessels is a problem that needs to be solved in this field. Summary of the invention

[0007] In view of the technical problem that existing offshore oil support vessels have low environmental friendliness due to the use of fuel oil, the purpose of the present invention is to provide an offshore oil support vessel using ammonia fuel, which can achieve "zero" emissions of the offshore oil support vessel and greatly improve the environmental friendliness of the oil support vessel.

[0008] In order to achieve the above-mentioned purpose, the present invention provides an offshore oil support vessel using ammonia fuel, comprising a main deck, and a bow peak tank, a bow thruster tank, an engine room, an ammonia fuel tank, a steering propeller tank and a stern ballast tank located below the main deck; the bow peak tank, bow thruster tank, engine room, ammonia fuel tank, a steering propeller tank and a stern ballast tank are divided and arranged in sequence from the bow to the stern by watertight transverse bulkheads; ammonia fuel filling stations are provided on both sides of the main deck; the ammonia fuel filling stations pass through the deck to the ammonia fuel tank; the ammonia fuel tank is connected to the engine room through a transmission pipeline.

[0009] Furthermore, an ammonia fuel storage tank is arranged inside the ammonia fuel tank, and the ammonia fuel storage tank is separated from the main deck by airtightness; a cold box is provided at the end of the ammonia fuel storage tank.

[0010] Furthermore, the cold box is equipped with an ammonia fuel processing device to process the ammonia fuel in the ammonia fuel storage tank into a state suitable for use by the ammonia fuel transmitter; the cold box is also provided with a heat exchange unit to heat the ammonia fuel in the ammonia fuel storage tank and provide a gasification heat source; the cold box is provided with an airlock, which is an airtight structure and adopts a positive pressure ventilation structure.

[0011] Furthermore, the ammonia fuel filling station is equipped with an air intake pipeline, an air return pipeline, a valve, a temperature sensor and a pressure sensor;

[0012] One end of the air intake pipeline is connected to the ammonia fuel filling station, and the other end is connected to the ammonia fuel storage tank, and the fuel is filled from the filling station into the ammonia fuel storage tank through the air intake pipeline;

[0013] The return air pipeline is arranged between the filling station and the ammonia fuel storage tank, and the volatilized gas is returned to the filling station through the return air pipeline; the valve is arranged on the air intake pipeline and the return air pipeline;

[0014] The temperature sensor and the pressure sensor are arranged on the air intake pipeline and the air return pipeline, and the temperature and pressure of the medium in the pipeline are detected by the temperature sensor and the pressure sensor.

[0015] Furthermore, the engine room is located in the bow of the ship, and an independent power distribution room is separately arranged in the cabin, and the power distribution board room is embedded in the engine room;

[0016] The cabin is provided with a plurality of ammonia fuel generator sets which are connected to the ammonia fuel storage tank through double-walled pipes. The ammonia fuel generator sets are longitudinally arranged in the cabin and connected to the distribution board room through cables. The electric energy of the ammonia fuel generator sets is transmitted to the distribution board room through cables, and then distributed to each user through the distribution board room.

[0017] Furthermore, the rudder propeller cabin is provided with an azimuth propeller, a propulsion motor, a propulsion transformer and a propulsion frequency converter; the propulsion motor is driven and connected to the azimuth propeller to provide power for the azimuth propeller; the propulsion frequency converter is connected to the propulsion transformer and cooperates with the propulsion motor to control the rotation speed of the propulsion motor.

[0018] Furthermore, the double-walled pipe and the cold box adopt a negative pressure ventilation structure; a combustible gas detector and a negative pressure sensor are arranged inside the cold box to monitor the combustible gas inside the cold box and the environmental negative pressure value.

[0019] Furthermore, the negative pressure ventilation structure and the exhaust outlet of the cold box are led to the top of the hull through pipelines, and a ventilation mast is arranged on the top of the hull of the offshore oil support vessel to discharge the gas released by the negative pressure ventilation and the cold box through the ventilation mast.

[0020] Furthermore, a streamlined forecastle is arranged at the bow of the oil support vessel, and a main deck is arranged behind the forecastle; the entire oil support vessel adopts a fully welded steel hull, a mixed frame, and has a continuous main deck.

[0021] Furthermore, five deckhouses, namely, forecastle deck, upper forecastle deck, captain's deck, navigation deck and top deck, are sequentially stacked on the main deck; a breathable mast is arranged on the top deck.

[0022] The present solution provides an offshore oil support vessel using ammonia fuel, which uses ammonia as the fuel for the hull power and safely arranges the tank for storing ammonia fuel on the hull, thereby successfully using ammonia as the fuel for the hull, greatly improving the environmental friendliness of the oil support vessel. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0024] Figure 1 A structural side view of an offshore oil support vessel using ammonia fuel;

[0025] Figure 2 A top view of the structure of an offshore oil support vessel using ammonia fuel.

[0026] The following is a description of the components in the accompanying drawings:

[0027] 100. Main deck 120. Forecastle deck 130. Upper forecastle deck 140. Captain's deck 150. Navigation deck 160. Top deck 200. Forepeak tank 210. Bow thruster tank 210a. Pipe thruster 220. Engine room 220a. Generator set 230. Ammonia fuel tank 230a. Ammonia fuel storage tank 230b. Cold box 230c. Double-walled pipe 230d. Heat exchange unit 230e. Airlock 240. Rudder propeller compartment 240a. Full-turn propeller 240b. Propulsion motor 240c. Propulsion transformer 240d. Propulsion inverter 250. Aft ballast tank 260. Platform deck 270. Double bottom 280. Fresh water tank 290. Ballast tank / drilling water tank 300. Breathable mast 310. Switchboard room 320. Ammonia fuel filling station 320. Filling pipeline. DETAILED DESCRIPTION

[0028] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further described below with reference to specific diagrams.

[0029] In view of the technical problem that existing offshore oil support vessels cannot achieve "zero" emissions due to the use of fuel oil, based on this technical problem, the purpose of this solution is to provide an offshore oil support vessel using ammonia fuel, which can achieve true "zero" emissions by developing ammonia fuel, a clean energy source, as the main fuel for offshore oil support vessels and applying ammonia fuel to offshore oil support vessels.

[0030] The current "green energy" such as LNG, LPG, ethane fuel or hybrid battery propulsion cannot completely achieve zero carbon emissions, so all parties have been exploring the development of zero carbon emission ships. Ammonia fuel can achieve true "zero" emissions and will bring cleaner energy to shipping.

[0031] Ammonia (NH3) fuel, as a nitrogen-hydrogen compound, has the characteristics of stable supply, easy storage and transportation, and does not produce greenhouse gas carbon dioxide when burned. Therefore, liquefied gas ships powered by ammonia fuel can effectively reduce carbon oxides and sulfur oxides, achieving true "zero" emissions.

[0032] The functions of offshore oil support vessels (OSVs) determine that their ship types have their own characteristics, such as the living cabins are usually located at the bow, there is a large area of ​​working deck in the middle and rear of the ship, and the radar mast is located at the bow. Moreover, this type of ship is usually small in size, powerful in function, compact in space, and has a variety of equipment. The application of ammonia fuel to offshore oil support vessels requires the basic functions of this type of ship to be realized, and the storage, processing, application, leakage treatment, equipment matching and other factors of ammonia fuel should be considered comprehensively to achieve the safe, reliable and stable use of ammonia fuel on this type of ship.

[0033] See also Figure 1-Figure 2 The marine oil support vessel using ammonia fuel provided by the present invention is divided into a forepeak tank 200, a bow thruster tank 210, an engine room 220, an ammonia fuel tank 230, a rudder propeller tank 240 and a stern ballast tank 250 from bow to stern through watertight transverse bulkheads.

[0034] By using watertight transverse bulkheads to divide each compartment, the hull can be made watertight under specified water pressure, thus protecting the sealing of the compartment well.

[0035] The bow thruster compartment 210 of the ship is located at the bow, and a pipeline thruster 210 a is arranged in the bow thruster compartment 210 .

[0036] The engine room 220 is of intrinsically safe type and is located in the bow of the ship. A switchboard room 310 is provided in the engine room 220 and is embedded in the engine room 220 for arranging electrical related equipment.

[0037] Since the environment of the cabin 220 is relatively harsh, the switchboard room 310 is a delicate electrical product that needs to meet higher environmental requirements. Therefore, an independent space can be further provided in the cabin 220 for arranging the switchboard room 310.

[0038] We do not limit the technical solution of further setting up an independent distribution panel room 310 in the cabin 220. It can also be set adjacent to the cabin 220. The specific setting plan can be determined according to actual requirements.

[0039] An ammonia fuel generator set 220a is arranged in the engine room 220. The engine of the ammonia fuel generator set 220a is of intrinsically safe type. A plurality of intrinsically safe ammonia fuel generator sets 220a form a power station to provide electricity for the ship.

[0040] At the same time, due to the harsh cabin environment, the ammonia fuel generator set 220a is preferably arranged longitudinally in the cabin 220. The longitudinal arrangement can facilitate the operation, maintenance and heat dissipation of the equipment in harsh environments.

[0041] The ammonia fuel power generation group 220a is connected to the distribution board room 310 through a cable, and the electric energy of the ammonia fuel power generation group 220a is transmitted to the distribution board room 310 through the cable, and then distributed to each user through the distribution board room 310.

[0042] Usually, the switchboard room 310 and the ammonia fuel generator set 220a are managed by a power plant management system to ensure safe, reliable and economical operation of the generator set.

[0043] The ammonia fuel tank 230 is located in a special compartment under the main deck 100, and the distance between it and the hull outer plating and bulkhead meets the requirements of specifications and regulations.

[0044] An ammonia fuel storage tank 230a is provided inside the ammonia fuel tank 230. The ammonia fuel storage tank 230a is arranged inside the ammonia fuel tank 230 under the deck of the cargo area and adopts airtight separation to minimize possible damage to the storage tank due to collision, thereby ensuring the safety of ammonia fuel storage.

[0045] The ammonia fuel storage tank 230a adopts a C-type tank, which uses the cold preservation and pressure maintenance of ammonia fuel to reduce escape, and modular supply, utilization, construction and installation. A cold box is set at the end.

[0046] An airtight cold box 230b is attached to the end of the ammonia fuel storage tank 230a, and the ammonia fuel storage tank is connected to the ammonia fuel generator set 220a inside the cabin to provide a power source for the ammonia fuel generator set 220a.

[0047] The cold box 230b has an ammonia fuel processing device built in, which processes the ammonia fuel into a state suitable for use by the ammonia fuel generator.

[0048] A water / ethylene glycol mixed liquid heat exchange unit 230d is provided in the cold box 230b, which utilizes the waste heat of the ammonia fuel engine group 220a as a heat source for heating and gasification of the ammonia fuel.

[0049] The cold box 230b is provided with an airlock 230e. The airlock 230e is of airtight design and adopts positive pressure ventilation to ensure the isolation of the cold box 230b and external hazards. The relevant design meets the requirements of the classification society.

[0050] At the same time, a combustible gas detector is also provided in the cold box 230b. The probe of the combustible gas detector is inserted into the cold box 230b so as to monitor the combustible gas that may exist in the environment inside the cold box 230b.

[0051] Likewise, a negative pressure sensor is provided inside the cold box 230b to monitor the negative pressure value of the environment inside the cold box 230b.

[0052] The hull of this solution adopts electric propulsion, and the rudder and propeller compartment 240 is located at the stern. The rudder and propeller compartment 240 is provided with an azimuth propeller 240a, a propulsion motor 240b, a propulsion transformer 240c and a propulsion frequency converter 240d.

[0053] The propulsion of the ship mainly relies on the thrust generated by the rotation of the azimuth propeller 240a installed at the stern of the ship; the propulsion motor 240b drives the azimuth propeller 240a to provide power to the azimuth propeller 240a, so that it rotates and provides thrust.

[0054] The propulsion inverter 240d is connected to the propulsion transformer 240c and cooperates with the propulsion motor 240b to control the speed of the propulsion motor 240b, so as to adjust the propeller speed and propeller thrust direction of the propeller, thereby controlling the navigation of the ship.

[0055] This solution arranges the living and service areas at the bow of the hull, with the engine room 220 located in the middle bow, the ammonia fuel tank 230 located in a special cabin under the main deck 100 and away from the living cabin, the rudder and propeller compartment 240 and the rear ballast tank 250 located at the rear. This comprehensive layout minimizes the damage to the layout of this type of ship and ensures the usage habits of the crew of this type of ship.

[0056] The bow is arranged with a streamlined forecastle and a compact superstructure, and the bow adopts a closed (or semi-closed, or open) structure. The whole ship adopts a fully welded steel hull, a mixed frame, and has a continuous main deck 100. The main deck 100 behind the forecastle is provided with a deck cargo area and an operation area.

[0057] Five deckhouses, namely, a forecastle deck 120, an upper forecastle deck 130, a captain's deck 140, a navigation deck 150 and a top deck 160, are sequentially stacked on the main deck 100.

[0058] The top deck 160 is provided with a ventilation mast 300, on which are disposed a plurality of signal cross bars and a ventilation pipeline connected to the exhaust gas generating equipment in the hull, for discharging exhaust gas and transmitting signals.

[0059] Below the main deck 100 are a platform deck 260, a double bottom 270, a fresh water tank 280, a ballast tank / drilling water tank 290, and a mud tank.

[0060] At the same time, several bulk tanks can be set up according to needs to load bulk cargo.

[0061] The construction and installation of the platform deck 260, double bottom 270, fresh water tank 280, ballast tank / drilling water tank 290, mud tank and bulk tank are well known to those skilled in the art and will not be described in detail here.

[0062] Ammonia fuel filling stations 320 are provided on both sides of the main deck 100. The filling pipeline passes through the main deck 100 to the cold box 230b, and then enters the interior of the ammonia fuel storage tank 230a to fill the ammonia fuel storage tank through the filling pipeline.

[0063] The ammonia fuel filling station 320 adopts a modular design, which can facilitate the subsequent installation and unloading. It is equipped with an air intake pipeline, a return air pipeline, a valve, a temperature sensor and a pressure sensor.

[0064] The air intake pipeline is used for filling ammonia fuel, one end of which is connected to the ammonia fuel filling station 320, and the other end is connected to the ammonia fuel storage tank 230a. The fuel is filled from the ammonia fuel filling station 320 into the ammonia fuel storage tank 230a on the ship through this air intake pipeline.

[0065] Due to factors such as the volatility of the ammonia fuel in the ammonia fuel storage tank 230a, part of the ammonia fuel evaporates into gas. Therefore, a return air pipeline is set between the ammonia fuel storage tank 230a and the ammonia fuel filling station 320 to return the volatilized gas to the ammonia fuel filling station 320 through the return air pipeline so that the filling operation can proceed continuously and smoothly.

[0066] Several valves are set on the air intake pipeline and the air return pipeline to control the opening and closing of the pipeline.

[0067] Temperature sensors and pressure sensors are installed on the air intake and return lines to detect the temperature and pressure of the medium in the pipes and to guide the filling operation.

[0068] In this solution, the structure of the valve can be opened manually or controlled remotely; the structure of the temperature sensor and the pressure sensor can be displayed locally or remotely.

[0069] The fuel in the ammonia fuel storage tank 230a is gasified and heated, and then provided to the ammonia fuel engine through the double-walled pipe 230c gas supply pipeline.

[0070] The double-walled pipe 230c and the cold box 230b use negative pressure ventilation, with the ventilation frequency not less than 30 times per hour, and a combustible gas detector and a negative pressure sensor are installed in the cold box 230b to ensure the stable and effective operation of the system and to ensure that the ammonia fuel that may leak can be drained in time. The negative pressure exhaust and the safety release valve of the ammonia fuel storage tank 230a are led to the ventilation mast 300 installed on the top of the hull for discharge. The ventilation mast 300 is integrated with the signal mast, and the height of the ventilation mast meets the standard setting requirements, ensuring that the dangerous area brought by the ventilation mast 300 does not affect the layout and use of the ship, and ensuring the safety of the ship.

[0071] Here, there is no separate ventilation mast 300 for the ventilation and air permeability related to ammonia fuel. Instead, they all share one ventilation mast 300 and are integrated with the signal mast, thereby intensively arranging the space.

[0072] The pipeline between the ammonia fuel storage tank 230a and the air-permeable mast 300 can be supported and fixed by providing a supporting and fixing assembly, so that the installation of the ammonia fuel pipeline has sufficient flexibility to prevent it from being mechanically damaged.

[0073] At the same time, hoses and flanges should be used as little as possible on the ammonia fuel pipeline, and sliding expansion joints should not be used, because sliding joints mean expansion and contraction displacement, which brings potential leakage risks.

[0074] In summary, the difference between the offshore oil support vessel using ammonia fuel provided by this solution and the offshore oil support vessel using conventional fuel oil as fuel is as follows: This solution innovatively introduces ammonia fuel into this ship. Ammonia fuel is the next generation of environmentally friendly fuel. Ammonia does not emit carbon dioxide when burned. Ammonia fuel-propelled ships can meet the International Maritime Organization (IMO)'s 2050 shipping industry carbon reduction targets.

[0075] Reasonable design is carried out around the layout and interface matching of ammonia fuel filling, storage, supply, ventilation, and breathability to ensure the safety, reliability and stability of the charter ship.

[0076] At the same time, the engine room and ammonia fuel storage tank tanks on the support ship are both intrinsically safe and designed in accordance with the highest level of safety standards, ensuring the safety of the ship's use.

[0077] In addition, its ammonia fuel-related equipment, such as ammonia fuel filling stations, ammonia fuel storage tanks, cold boxes at the ends of ammonia fuel storage tanks, ammonia fuel engines, etc., adopt modular, partitioned layout, and intensive assembly to facilitate installation, use, and maintenance.

[0078] The ship type provided by this solution not only meets the basic functions of an offshore oil support vessel (OSV), but also successfully applies the ammonia fuel power system within the limited hull space.

[0079] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. An offshore oil support vessel using ammonia fuel, characterized in that: It includes a main deck, and a forepeak tank, a bow thruster tank, an engine room, an ammonia fuel tank, a rudder and propeller tank and aft ballast tank located below the main deck; the forepeak tank, bow thruster tank, engine room, ammonia fuel tank, rudder and propeller tank and aft ballast tank are divided and arranged in sequence from the bow to the stern by watertight transverse bulkheads; The ammonia fuel tank is located in a special cabin under the main deck, and an ammonia fuel storage tank is arranged inside the ammonia fuel tank, and the ammonia fuel storage tank is connected to the ammonia fuel generator set inside the engine room; a cold box is arranged at the end of the ammonia fuel storage tank, and an ammonia fuel processing device and a water / ethylene glycol mixed liquid heat exchange unit are built in the cold box, and the ammonia fuel in the ammonia fuel storage tank is processed into a state suitable for use by the ammonia fuel generator set by the ammonia fuel processing device; the water / ethylene glycol mixed liquid heat exchange unit uses the waste heat of the ammonia fuel generator set as a heating and gasification heat source of the ammonia fuel to heat and gasify the ammonia fuel; ammonia fuel filling stations are arranged on both sides of the main deck through modular design to facilitate subsequent installation and unloading, and the ammonia fuel filling stations pass through the deck to the ammonia fuel tank, and fill the ammonia fuel storage tank through a filling pipeline, and the ammonia fuel tank is connected to the engine room through a transmission pipeline, and the ammonia fuel processed by the ammonia fuel processing device is sent to the engine room for use; The engine room is located in the bow of the ship, and an independent distribution room is separately arranged in the cabin, and the distribution board room is embedded in the engine room; a plurality of ammonia fuel generator sets are arranged in the engine room and are connected to the ammonia fuel storage tank through double-walled pipes, and the ammonia fuel generator sets are longitudinally arranged in the engine room and connected to the distribution board room through cables, and the electric energy of the ammonia fuel generator sets is transmitted to the distribution board room through cables, and then distributed to each user through the distribution board room.

2. The offshore oil support vessel using ammonia fuel according to claim 1, characterized in that: The ammonia fuel storage tank is airtightly separated from the main deck.

3. The offshore oil support vessel using ammonia fuel according to claim 1, characterized in that: The cold box is provided with an airlock, which is an airtight structure and adopts a positive pressure ventilation structure.

4. The offshore oil support vessel using ammonia fuel according to claim 1, characterized in that: The ammonia fuel filling station is equipped with an air intake pipeline, an air return pipeline, a valve, a temperature sensor and a pressure sensor; One end of the air intake pipeline is connected to the ammonia fuel filling station, and the other end is connected to the ammonia fuel storage tank, and the fuel is filled from the filling station into the ammonia fuel storage tank through the air intake pipeline; The return air pipeline is arranged between the filling station and the ammonia fuel storage tank, and the volatilized gas is returned to the filling station through the return air pipeline; the valve is arranged on the air intake pipeline and the return air pipeline; The temperature sensor and the pressure sensor are arranged on the air intake pipeline and the air return pipeline, and the temperature and pressure of the medium in the pipeline are detected by the temperature sensor and the pressure sensor.

5. The offshore oil support vessel using ammonia fuel according to claim 1, characterized in that: The rudder propeller cabin is provided with an azimuth propeller, a propulsion motor, a propulsion transformer and a propulsion frequency converter; the propulsion motor is driven and connected to the azimuth propeller to provide power for the azimuth propeller; the propulsion frequency converter is connected to the propulsion transformer and cooperates with the propulsion motor to control the rotation speed of the propulsion motor.

6. The offshore oil support vessel using ammonia fuel according to claim 1, characterized in that: The double-walled pipe and the cold box adopt a negative pressure ventilation structure; a combustible gas detector and a negative pressure sensor are arranged inside the cold box to monitor the combustible gas inside the cold box and the environmental negative pressure value.

7. The offshore oil support vessel using ammonia fuel according to claim 6, characterized in that: The negative pressure ventilation structure and the exhaust outlet of the cold box are led to the top of the hull, and a ventilation mast is arranged on the top of the hull of the offshore oil support vessel to discharge the gas released by the negative pressure ventilation and the cold box through the ventilation mast.

8. The offshore oil support vessel using ammonia fuel according to claim 1, characterized in that: The bow of the oil support vessel is arranged with a streamlined forecastle, and a main deck is arranged behind the forecastle; the entire oil support vessel adopts a fully welded steel hull, a mixed frame, and has a continuous main deck.

9. The offshore oil support vessel using ammonia fuel according to claim 8, characterized in that: The main deck is provided with five deckhouses, namely, forecastle deck, upper forecastle deck, captain's deck, driving deck and top deck in sequence; a breathable mast is provided on the top deck.

Images