CN219159076U

CN219159076U - Heat exchange system of marine natural gas fuel

Info

Publication number: CN219159076U
Application number: CN202320359861.3U
Authority: CN
Inventors: 罗哲; 于海东; 肖学文; 蒋孙建; 杨国祥; 李阳
Original assignee: China International Marine Containers Group Co Ltd; CIMC Enric Investment Holdings Shenzhen Co Ltd; Jingmen Hongtu Special Aircraft Manufacturing Co Ltd
Current assignee: China International Marine Containers Group Co Ltd; CIMC Enric Investment Holdings Shenzhen Co Ltd; Jingmen Hongtu Special Aircraft Manufacturing Co Ltd
Priority date: 2023-02-28
Filing date: 2023-02-28
Publication date: 2023-06-09
Anticipated expiration: 2033-02-28

Abstract

The application discloses a heat exchange system of marine natural gas fuel, which comprises a heat exchanger, at least one LNG fuel vaporizer, pump set equipment, a temperature control valve and a first temperature sensor; the liquid outlet end of the pump set equipment is connected with the cooling liquid inlet of the heat exchanger through a first pipeline, the temperature control valve is connected with the cooling liquid outlet of the heat exchanger through a second pipeline, the temperature control valve is connected with the cooling liquid inlet of the LNG fuel vaporizer through a third pipeline, a fourth pipeline is connected between the cooling liquid outlet of the LNG fuel vaporizer and the liquid inlet end of the pump set equipment, the temperature control valve is connected with the liquid inlet end of the pump set equipment through a fifth pipeline, and the first temperature sensor is connected with the gas outlet end of the LNG fuel vaporizer; the heat exchange system can keep the outlet air temperature of the LNG fuel vaporizer in a constant temperature range, so that the running stability of the host engine is ensured.

Description

Heat exchange system of marine natural gas fuel

Technical Field

The application relates to the field of marine fuel heat exchange equipment, in particular to a marine natural gas fuel heat exchange system.

Background

Liquefied Natural Gas (LNG) is used as a novel ship energy source, and has the advantages of low carbon, environmental protection, economy and the like. The natural gas fuel power ship uses natural gas fuel as driving fuel, however, the existing marine LNG fuel heat exchange system has no fuel temperature control and regulation function, the fuel temperature fluctuation after LNG gasification is large, and the use function of a marine natural gas engine is unstable and even the marine natural gas engine is stopped in a fault manner easily.

It can be seen that there is a need for improvements and improvements in the art.

Disclosure of Invention

In view of the above-described deficiencies of the prior art, it is an object of the present application to provide a heat exchange system for marine natural gas fuel that aims to provide a natural gas fuel engine with a temperature stable natural gas fuel.

In order to achieve the above purpose, the present application adopts the following technical scheme:

in one aspect, the application discloses a heat exchange system for marine natural gas fuel, comprising:

a heat exchanger and at least one LNG fuel vaporizer;

the liquid outlet end of the pump set equipment is connected with the cooling liquid inlet of the heat exchanger through a first pipeline;

the temperature control valve is connected with a cooling liquid outlet of the heat exchanger through a second pipeline, the temperature control valve is connected with a cooling liquid inlet of the LNG fuel vaporizer through a third pipeline, a fourth pipeline is connected between the cooling liquid outlet of the LNG fuel vaporizer and a liquid inlet end of the pump set equipment, and the temperature control valve is connected with the liquid inlet end of the pump set equipment through a fifth pipeline;

and the first temperature sensor is connected with the air outlet end of the LNG fuel vaporizer.

In some embodiments of the present application, the heat exchange system further comprises:

the first stop valve is connected to the first pipeline;

the pressure sensor is connected to the first pipeline and is arranged between the pump set equipment and the first stop valve.

the second temperature sensor is arranged at the cooling liquid inlet end of the heat exchanger and is connected to the first pipeline;

and the third temperature sensor is arranged at the cooling liquid outlet end of the heat exchanger and is connected to the second pipeline.

and the flowmeter is connected to the fourth pipeline and is used for detecting the flow of the cooling liquid in the fourth pipeline.

and the first stop check valve is connected to the fourth pipeline and is arranged at the downstream of the flowmeter.

In some embodiments of the present application, a first ventilation opening is provided on the fourth pipe, and the first ventilation opening is provided at the highest point of the fourth pipe in the vertical direction;

the heat exchange system further comprises:

the expansion tank, be provided with second ventilative mouth, filling opening, return port, liquid outlet and moisturizing mouth on the expansion tank, the second ventilative mouth with the filling opening set up in the top of expansion tank, the return port with expansion tank's gaseous phase space intercommunication, just the return port with first ventilative mouth passes through sixth pipeline connection, the liquid outlet with pump package equipment's feed liquor end passes through seventh pipeline connection, the moisturizing mouth set up in expansion tank's upper portion is configured can be to make up fresh water in the expansion tank.

the liquid level meter is arranged in the expansion water tank.

In some embodiments of the present application, at least one water inlet and at least one water outlet are further disposed on the heat exchanger, the water inlet is configured to be connected with a water outlet of the main engine cylinder liner water, the water outlet is configured to be connected with a water return port of the main engine cylinder liner water, and a direction of entering and exiting the heat exchanger of the main engine cylinder liner water is opposite to a direction of entering and exiting the heat exchanger of the cooling liquid.

In some embodiments of the present application, two groups of heat exchange tubes, and two water outlets and two water inlets are disposed on the heat exchanger, and two ends of each group of heat exchange tubes are respectively connected with one water outlet and one water inlet.

In some embodiments of the present application, the heat exchange system is configured with two LNG fuel vaporizers, a first end of the second pipe is connected to the coolant outlet of the heat exchanger, a second end of the second pipe forms a first branch pipe and a second branch pipe, and the first branch pipe and the second branch pipe are respectively connected to a temperature control valve.

In some embodiments of the present application, the temperature control valve is a three-way valve, including first entry, first export and second export, first entry passes through the second pipeline with the coolant outlet connection of heat exchanger, first export passes through the third pipeline with the coolant inlet connection of LNG fuel vaporizer, the second export pass through the fifth pipeline with the feed liquor end connection of pump package equipment.

In some embodiments of the present application, a second stop valve is disposed between the first outlet and the coolant inlet of the LNG fuel vaporizer, and the second stop valve is connected to the third pipe.

The beneficial effects are that:

the application provides a heat transfer system of marine natural gas fuel, through set up the temperature after the gasification of first temperature sensor at the end of giving vent to anger of LNG fuel vaporizer, and set up pump package equipment at the coolant liquid entrance point of heat exchanger, set up the temperature control valve between the coolant liquid exit end of heat exchanger and LNG fuel vaporizer, the temperature of giving vent to anger of the feedback of first temperature sensor is received to the temperature control valve, the flow of the coolant liquid in the control entering LNG fuel vaporizer, the heat transfer effect of adjustment coolant liquid and natural gas fuel, the temperature of the natural gas fuel after messenger's gasification remains in a invariable temperature range, thereby guarantee the stability of host engine function.

Drawings

Fig. 1 is a schematic structural diagram of a heat exchange system for marine natural gas fuel according to an embodiment of the present application.

Description of main reference numerals: 1. a heat exchanger; 101. a water inlet; 102. a water outlet; 103. a heat exchange tube; 2. an LNG fuel vaporizer; 3. a pump unit; 4. a temperature control valve; 401. a first inlet; 402. a first outlet; 403. a second outlet; 5. a first temperature sensor; 6. a first stop valve; 7. a pressure sensor; 8. a second temperature sensor; 9. a third temperature sensor; 10. a flow meter; 11. a first stop check valve; 12. a first ventilation port; 13. an expansion tank; 1301. a second ventilation port; 1302. a liquid adding port; 1303. a return port; 1304. a liquid outlet; 1305. a water supplementing port; 14. a liquid level gauge; 15. a second shut-off valve; 01. a first pipe; 02. a second pipe; 021. a first branch pipe; 022. a second branch pipe; 03. a third conduit; 04. a fourth conduit; 05. a fifth pipe; 06. a sixth conduit; 07. and a seventh pipeline.

Detailed Description

The application provides a heat exchange system of marine natural gas fuel, which is used for making the purposes, technical schemes and effects of the application clearer and more definite, and is further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the present application.

In the description of the present application, it should be understood that the terms "upper," "lower," "left," "right," and the like indicate an orientation or a positional relationship based on that shown in the drawings, and are merely for convenience of description of the present application and for simplification of the description, and do not indicate or imply that the apparatus or element in question must have a specific orientation, as well as a specific orientation configuration and operation, and therefore, should not be construed as limiting the present application. Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include one or more such feature. In the description of the present application, unless otherwise indicated, the meaning of "a plurality" is two or more.

In the description of the present application, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be either fixedly connected, detachably connected, or integrally connected, for example; can be mechanically connected, electrically connected or can be communicated with each other; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the terms in this application will be understood by those of ordinary skill in the art as the case may be.

Referring to fig. 1, the present application provides a heat exchange system for marine natural gas fuel, comprising a heat exchanger 1, at least one LNG fuel vaporizer 2, and a pump unit 3, a temperature control valve 4 and a first temperature sensor 5; the liquid outlet end of the pump set device 3 is connected with the cooling liquid inlet of the heat exchanger 1 through a first pipeline 01, so as to pressurize and input cooling liquid into the heat exchanger 1, the temperature control valve 4 is connected with the cooling liquid outlet of the heat exchanger 1 through a second pipeline 02, the temperature control valve 4 is connected with the cooling liquid inlet of the LNG fuel vaporizer 2 through a third pipeline 03, a fourth pipeline 04 is connected between the cooling liquid outlet of the LNG fuel vaporizer 2 and the liquid inlet end of the pump set device 3, and the temperature control valve 4 is connected with the liquid inlet end of the pump set device 3 through a fifth pipeline 05; the first temperature sensor 5 is connected to the gas outlet end of the LNG fuel vaporizer 2.

In the above, the pump unit 3, the heat exchanger 1, the temperature control valve 4 and the LNG fuel vaporizer 2 are sequentially connected to form a first circulation loop; the pump set device 3, the heat exchanger 1 and the temperature control valve 4 are sequentially connected to form a second circulation loop. The exhaust end of the LNG fuel vaporizer 2 is connected with a host engine, and the cooling liquid enters the LNG fuel vaporizer 2 to exchange heat with LNG fuel through a temperature control valve 4 after heat exchange and temperature rise in the heat exchanger 1 or returns to the pump group device 3 to be introduced into the heat exchanger 1 again.

The temperature control valve 4 is a three-way valve and is provided with two outlets, and the cooling liquid can be distributed between the third pipeline 03 and the fifth pipeline 05 by controlling the opening degrees of different outlets, so that the heat exchange effect of the cooling liquid and the natural gas fuel can be adjusted. Specifically, the first temperature sensor 5 monitors the temperature of the natural gas discharged from the LNG fuel vaporizer 2, and feeds back the temperature information to the temperature control valve 4, and the temperature control valve 4 adjusts the opening of the two outlets according to the received temperature information, so that the flow rate of the cooling liquid entering the LNG fuel vaporizer 2 is changed, and the heat exchange effect of the cooling liquid and the natural gas fuel is changed, so that the temperature of the natural gas fuel passing through the LNG fuel vaporizer 2 is stabilized at 5-25 ℃, and the stability of the fuel supply temperature of the marine engine is ensured, and the marine engine is enabled to stably operate. For example, when the first temperature sensor 5 detects that the temperature of the natural gas fuel discharged from the LNG fuel vaporizer 2 is lower than 5 ℃, the opening of the thermo valve 4 connected to the heat exchanger 1 is completely opened, so that the coolant is entirely introduced into the LNG fuel vaporizer 2 through the third pipe 03, and the temperature of the fuel is increased. As another example, when the first temperature sensor 5 detects that the temperature of the natural gas fuel exiting the LNG fuel vaporizer 2 is higher than 25 ℃, the opening of the thermostatic valve 4 connected to the fifth pipe 05 is opened by 90%, reducing the flow of cooling liquid into the LNG fuel vaporizer 2, allowing more cooling liquid to return from the fifth pipe 05 to the pump stack apparatus 3, reducing the temperature of the natural gas fuel.

In this embodiment, the coolant is an ethylene glycol solution. The glycol has high boiling point and low freezing point, can be mixed with water in any proportion, and the freezing point of the solution is different according to the difference of the content of the diethanol in the solution. In addition, the ethylene glycol has less volatilization loss and long service period, and is an ideal cooling liquid.

In this application, heat exchanger 1 lets in main engine cylinder liner water and carries out the heat exchange with the coolant liquid, and the heat energy of effective cyclic utilization engine improves this heat transfer system's economic nature.

Further, the heat exchange system also comprises a first stop valve 6 and a pressure sensor 7; the first shut-off valve 6 is connected to the first conduit 01, and the pressure sensor 7 is connected to the first conduit 01 and arranged between the pump unit 3 and the first shut-off valve 6. The cooling liquid is pressurized by the pump set equipment 3 and then enters the heat exchanger 1 through the first stop valve 6 to perform heat exchange and temperature rise, and when the pressure sensor 7 detects that the pressure is too low, the pump set equipment 3 can be automatically started to perform pressurization.

Further, the heat exchange system also comprises a second temperature sensor 8 and a third temperature sensor 9; the second temperature sensor 8 is arranged at the cooling liquid inlet end of the heat exchanger 1 and is connected to the first pipeline 01; the third temperature sensor 9 is provided at the coolant outlet end of the heat exchanger 1 and connected to the second pipe 02. The second temperature sensor 8 is used for detecting the temperature of the cooling liquid entering the heat exchanger 1, the third temperature sensor 9 is used for detecting the temperature of the cooling liquid discharged out of the heat exchanger 1, and the heat exchange effect of the heat exchanger 1 can be monitored by combining the second temperature sensor 8 and the third temperature sensor 9 so as to ensure the heat exchange effect of the cooling liquid and LNG.

Further, the heat exchange system further comprises a flow meter 10, wherein the flow meter 10 is connected to the fourth pipeline 04 and is used for detecting the flow rate of the cooling liquid in the fourth pipeline 04; during operation of the heat exchange system, the flow meter 10 should always detect that the cooling liquid flows in the fourth pipeline 04, that is, the cooling liquid always enters the LNG fuel vaporizer 2, so as to prevent freezing and icing inside the LNG fuel vaporizer 2.

Further, the heat exchange system further comprises a first stop check valve 11, wherein the first stop check valve 11 is connected to the fourth pipeline 04 and is arranged downstream of the flowmeter 10; the coolant on the fourth pipe 04 can be prevented from flowing reversely into the LNG fuel vaporizer 2.

Further, the fourth pipeline 04 is provided with a first ventilation port 12, and the first ventilation port 12 is arranged at the highest point of the fourth pipeline 04 along the vertical direction; the heat exchange system further comprises an expansion tank 13, the expansion tank 13 being arranged at the highest position of the heat exchange system, the expansion tank 13 being for loading cooling liquid for supplementing the heat exchange system with cooling liquid. In addition, a gas-phase space is formed at the upper part of the inner cavity of the expansion water tank 13, a backflow port 1303 is arranged on one side wall of the expansion water tank 13 corresponding to the gas-phase space, a second ventilation port 1301 is arranged at the top of the expansion water tank 13, the backflow port 1303 is connected with the first ventilation port 12 through a sixth pipeline 06, air or other gases in the fourth pipeline 04 are discharged into the gas-phase space of the expansion water tank 13 through the first ventilation port 12 and the sixth pipeline 06, and then the external environment is discharged through the second ventilation port 1301, so that the influence of the gases in the fourth pipeline 04 on the flow and pressure control of the cooling liquid is avoided.

The expansion tank 13 is further provided with a filling port 1302, a liquid outlet 1304 and a water supplementing port 1305, wherein the filling port 1302 is arranged at the top of the expansion tank 13 and is used for filling cooling liquid into the expansion tank 13. Preferably, a stop valve is further connected to the outside of the filling port 1302, and is opened when filling, and is not required to be closed when filling, so as to prevent the cooling liquid in the expansion tank 13 from evaporating or leaking. The liquid outlet 1304 is arranged at the bottom of the expansion water tank 13, is connected with the liquid inlet end of the pump set equipment 3 through a seventh pipeline 07, and is provided with a stop valve on the seventh pipeline 07, and is opened when the cooling liquid is needed to be replenished in the pump set equipment 3 and is closed when the cooling liquid is not needed to be replenished. The water supply port 1305 is provided at an upper portion of the expansion tank 13, and is configured to be able to supply fresh water to the expansion tank 13; during the operation of the heat exchange system, part of water may be evaporated, so that the contents of solute and water in the cooling liquid are changed, thereby causing the change of the heat conductivity coefficient of the cooling liquid; the fresh water is supplied to the expansion tank 13 at regular time or according to the frequency of use, so that the concentration of the coolant can be maintained within a stable range, and the stability of the supply air temperature of the LNG fuel vaporizer 2 to the host engine can be improved.

Further, the heat exchange system further comprises a liquid level meter 14, wherein the liquid level meter 14 is arranged in the expansion water tank 13 and is used for monitoring the liquid level condition in the expansion water tank 13, so that the freezing liquid can be timely replenished when the liquid level in the expansion water tank 13 is too low; and the liquid phase space and the gas phase space exist in the expansion water tank 13 when the refrigerating fluid is supplemented, and the backflow port 1303 corresponds to the gas phase space, so that the heat exchange tube 103 can exhaust gas into the gas phase space of the expansion water tank 13.

The heat exchanger 1 is also provided with at least one water inlet 101 and at least one water outlet 102, the water inlet 101 is configured to be connected with a water outlet 102 of the cylinder sleeve water of the main machine, the water outlet 102 is configured to be connected with a water return port of the cylinder sleeve water of the main machine, the direction of entering and exiting the heat exchanger 1 of the cylinder sleeve water of the main machine is opposite to the direction of entering and exiting the heat exchanger 1 of the cooling liquid, and the heat exchange effect is improved; in this application, heat exchanger 1 utilizes host computer cylinder liner water and coolant liquid heat transfer, and the heating coolant liquid has effectively cyclic utilization engine's heat energy, has improved this heat transfer system's economic nature and environmental protection performance.

In some embodiments, two groups of heat exchange tubes 103, two water outlets 102 and two water inlets 101 are arranged on the heat exchanger 1, two ends of each group of heat exchange tubes 103 are respectively connected with one water outlet 102 and one water inlet 101, each water outlet 102 is connected with a water return port of cylinder liner water of a host engine, and each water inlet 101 is connected with the water outlet 102 of cylinder liner water of the host engine, so that the heat exchanger 1 fully utilizes heat energy of two host engines, can basically meet the requirement of supplying air to the host engines after liquefied natural gas is heated to an ideal temperature, and reduces energy loss.

The two groups of heat exchange tubes 103 on the heat exchanger 1 are parallel to each other and are arranged on two axially opposite sides of the heat exchanger 1 at intervals, cooling liquid passes through the shell side of the heat exchanger 1, engine cylinder liner water passes through the tube side of the heat exchanger 1, so that the cooling liquid can fully contact with a pipeline for circulating the engine cylinder liner water, and the heat exchange effect is enhanced.

In some embodiments of the present application, the heat exchange system is configured with two LNG fuel vaporizers 2, each LNG fuel vaporizer 2 is correspondingly supplied with air to a host engine, liquefied natural gas is introduced from one end of the LNG fuel vaporizer 2, and is gasified from a liquid state to a gaseous state after heat exchange and temperature rise with the cooling liquid, and is discharged from the other end of the LNG fuel vaporizer 2 to the host engine. Each LNG fuel vaporizer 2 is in pipeline connection with the heat exchanger 1 and the pump unit 3, respectively, i.e. two LNG fuel vaporizers 2 are connected in parallel between the heat exchanger 1 and the pump unit 3. Specifically, a first end of the second pipe 02 is connected to a coolant outlet of the heat exchanger 1, a second end of the second pipe 02 forms a first branch pipe 021 and a second branch pipe 022, and the first branch pipe 021 and the second branch pipe 022 are respectively connected to a temperature control valve 4. The thermo valve 4 connected to the first branch 021 is connected to the coolant inlet of one of the LNG fuel vaporizers 2 via a third pipe 03 and to the pump unit 3 via a fifth pipe 05. Likewise, the thermo valve 4 connected to the second branch line 022 is also connected to the coolant inlet of the other LNG fuel vaporizer 2 via a third line 03, and to the pump unit 3 via a fifth line 05.

In order to simplify the arrangement of the lines, the fifth lines 05 connected to the two thermostatic valves 4 are connected to the pump unit 3 after they merge. Specifically, for convenience of description herein, the two LNG fuel vaporizers 2 respectively represent the first LNG fuel vaporizer 2 and the second LNG fuel vaporizer 2, the thermo valve 4 connected to the first LNG fuel vaporizer 2 is represented as a first thermo valve 4, and the thermo valve 4 connected to the second LNG fuel vaporizer 2 is represented as a second thermo valve 4. After the fifth pipeline 05 connected with the second temperature control valve 4 merges with the fourth pipeline 04 connected with the second LNG fuel vaporizer 2, the fourth pipeline 04 connected with the first LNG fuel vaporizer 2 merges downstream of the first stop check valve 11, and then the fifth pipeline 05 connected with the first temperature control valve 4 merges and is connected with the pump unit 3. In this way, the second pipeline 02 can be divided into a corresponding number of branch pipes according to the number of the LNG fuel vaporizer 2, and the structure is flexible and the applicability is high.

Further, the second pipe 02 is provided with a stop check valve, so that the coolant can be prevented from flowing back into the heat exchanger 1. The cut-off check valve is disposed upstream of the first and

second branches

021 and 022, so that a plurality of branches can be simultaneously controlled by one valve, simplifying the structure.

Further, the temperature control valve 4 is a three-way valve, and comprises a first inlet 401, a first outlet 402 and a second outlet 403, wherein the first inlet 401 is connected with a cooling liquid outlet of the heat exchanger 1 through a second pipeline 02, the first outlet 402 is connected with a cooling liquid inlet of the LNG fuel vaporizer 2 through a third pipeline 03, and the second outlet 403 is connected with a liquid inlet end of the pump set device 3 through a fifth pipeline 05; in the operation process of the heat exchange system, the opening degree of the first outlet 402 and the second outlet 403 of the temperature control valve 4 is switched to control the flow rate of the cooling liquid which is introduced into the LNG fuel vaporizer 2, and the heat exchange effect is adjusted so as to stabilize the air supply temperature of the LNG fuel vaporizer 2 to the host engine.

Different LNG fuel vaporizers 2 are controlled through independent temperature control valves 4, and the temperature control valves 4 on different branches acquire temperature data of a first temperature sensor 5 connected with the corresponding LNG fuel vaporizer 2, so that the flow of cooling liquid of the branch is independently controlled, and the control accuracy of the heat exchange effect of the heat exchange system is further improved.

Further, a second stop valve 15 is disposed between the first outlet 402 and the coolant inlet of the LNG fuel vaporizer 2, and the second stop valve 15 is connected to the third pipeline 03 for controlling the circulation of the coolant on the third pipeline 03.

The application also discloses a control method of the heat exchange system, which is applied to the heat exchange system described in any one of the above, and specifically comprises the following steps:

the refrigerating fluid is injected into the expansion water tank 13 from the fluid filling port 1302 at the top of the expansion water tank 13, flows out from the fluid outlet 1304 at the bottom of the expansion water tank 13, flows to the pump unit 3 through the seventh pipeline 07, the pump unit 3 pressurizes the refrigerating fluid and then conveys the cooling fluid to the heat exchanger 1, and meanwhile, engine cylinder liner water enters the heat exchanger 1 from the water inlet 101 of the heat exchanger 1 to exchange heat with the cooling fluid, so that the cooling fluid is heated and rises in temperature. The heat exchanged cooling liquid flows to the temperature control valve 4 through the second pipeline 02, and the flow rate of the cooling liquid entering the third pipeline 03 and the fifth pipeline 05 is distributed through the temperature control valve 4. The cooling liquid enters the LNG fuel vaporizer 2 through the third pipeline 03, exchanges heat with natural gas fuel, flows back to the pump set equipment 3 through the fourth pipeline 04, and directly flows back to the pump set equipment 3 through the fifth pipeline 05, and thus circularly flows.

In the above process, the pump set 3 is not always in a working state, and when the pressure sensor 7 at the liquid outlet end of the pump set 3 detects that the pressure of the cooling liquid is not less than a set value, the pump set 3 can be closed; when the pressure sensor 7 detects that the pressure of the cooling liquid is smaller than the set value, the pump set 3 may be activated. The first temperature sensor 5 connected with the air outlet end of the LNG fuel vaporizer 2 is used for always monitoring the air supply temperature of the LNG fuel vaporizer 2, feeding the data back to the temperature control valve 4, and adjusting the flow of cooling liquid entering the LNG fuel vaporizer 2 through the temperature control valve 4 so as to achieve the purpose of adjusting the air outlet temperature of the LNG fuel vaporizer 2.

Specifically, when the first temperature sensor 5 detects that the temperature of the air outlet end of the LNG fuel vaporizer 2 is lower than 5 ℃, the opening of the first outlet 402 of the temperature control valve 4 is increased, and the flow rate of the cooling liquid entering the LNG fuel vaporizer 2 is increased, so as to improve the heat exchange effect of the cooling liquid and the natural gas fuel, thereby improving the air outlet temperature of the LNG fuel vaporizer 2; when the first temperature sensor 5 detects that the temperature of the air outlet end of the LNG fuel vaporizer 2 is higher than 25 ℃, the opening of the first outlet 402 of the temperature control valve 4 is reduced, and the opening of the second outlet 403 is increased; the cooling liquid passing through the temperature control valve 4 flows back to the pump set equipment 3 through the fifth pipeline 05 more, so that the flow entering the LNG fuel vaporizer 2 is reduced, the heat exchange effect of the cooling liquid and the natural gas fuel is reduced, and the air outlet temperature of the LNG fuel vaporizer 2 is reduced; the temperature of the gas discharged by the LNG fuel vaporizer 2 is always kept within the range of 5-25 ℃, and the stability of the temperature of the gas supplied by the LNG fuel vaporizer 2 to the host engine is ensured.

Preferably, when the first temperature sensor 5 detects that the temperature of the air outlet end of the LNG fuel vaporizer 2 is lower than 5 ℃, the first outlet 402 of the temperature control valve 4 is completely opened, so that the natural gas fuel in the LNG fuel vaporizer 2 is quickly warmed up; when the first temperature sensor 5 detects that the temperature of the air outlet end of the LNG fuel vaporizer 2 is higher than 25 ℃, the second outlet 403 of the temperature control valve 4 is opened by 90%, so that the air outlet temperature of the LNG fuel vaporizer 2 can be quickly reduced, and cooling liquid is ensured to enter the LNG fuel vaporizer 2, and freezing and icing of the inside of the LNG fuel vaporizer 2 are prevented.

The second temperature sensor 8 and the third temperature sensor 9 also constantly monitor the temperature of the cooling liquid entering and exiting the heat exchanger 1, so that the stability of the heat exchange effect of the heat exchanger 1 is ensured. The flow meter 10 always detects the flow of the cooling liquid on the fourth pipeline 04, so that the cooling liquid always flows on the fourth pipeline 04, namely, the cooling liquid always enters the LNG fuel vaporizer 2, and the freezing and the icing inside the LNG fuel vaporizer 2 are prevented.

It will be understood that equivalents and modifications will occur to persons skilled in the art and may be made in accordance with the present utility model and its application and spirit, and all such modifications and substitutions are intended to be included within the scope of the following claims.

Claims

1. A heat exchange system for a marine natural gas fuel, comprising:

a heat exchanger and at least one LNG fuel vaporizer;

2. The marine natural gas fuel heat exchange system of claim 1, further comprising:

the first stop valve is connected to the first pipeline;

3. The marine natural gas fuel heat exchange system of claim 1, further comprising:

4. The marine natural gas fuel heat exchange system of claim 1, further comprising:

5. The marine natural gas fuel heat exchange system of claim 4 further comprising:

6. The marine natural gas fuel heat exchange system of claim 1 wherein,

the fourth pipeline is provided with a first ventilation opening, and the first ventilation opening is arranged at the highest point of the fourth pipeline along the vertical direction;

the heat exchange system further comprises:

7. The marine natural gas fuel heat exchange system of claim 6 further comprising:

the liquid level meter is arranged in the expansion water tank.

8. The marine natural gas fuel heat exchange system of claim 1, wherein the heat exchanger is further provided with at least one water inlet and at least one water outlet, the water inlet is configured to be connected with a main engine cylinder liner water outlet, the water outlet is configured to be connected with a main engine cylinder liner water return water inlet, and the direction of inlet and outlet of main engine cylinder liner water into and from the heat exchanger is opposite to the direction of inlet and outlet of cooling liquid into and from the heat exchanger.

9. The marine natural gas fuel heat exchange system according to claim 8, wherein the heat exchanger is provided with two groups of heat exchange tubes, and two water outlets and two water inlets, and two ends of each group of heat exchange tubes are respectively connected with one water outlet and one water inlet.

10. The marine natural gas fuel heat exchange system as claimed in claim 1, wherein the heat exchange system is provided with two LNG fuel vaporizers, a first end of the second pipe is connected to the coolant outlet of the heat exchanger, a second end of the second pipe forms a first branch pipe and a second branch pipe, and one temperature control valve is connected to each of the first branch pipe and the second branch pipe.

11. The marine natural gas fuel heat exchange system of any one of claims 1 to 10, wherein the temperature control valve is a three-way valve comprising a first inlet, a first outlet and a second outlet, the first inlet being connected to the coolant outlet of the heat exchanger by the second conduit, the first outlet being connected to the coolant inlet of the LNG fuel vaporizer by the third conduit, the second outlet being connected to the liquid inlet of the pump stack apparatus by a fifth conduit.

12. The marine natural gas fuel heat exchange system of claim 11 wherein a second shut-off valve is disposed between the first outlet and the coolant inlet of the LNG fuel vaporizer, the second shut-off valve being connected to the third conduit.