Dual-fuel engine air supply system with heat pump de-icing system and icing detection device

Abstract

This invention discloses a dual-fuel engine gas supply system with a heat pump de-icing system, comprising multiple gasification units, a compression heat pump system, and an icing detection device. The icing detection device can detect whether ice has formed on the surface of the gasification units. Any one of the gasification units can be used as a condenser of the compression heat pump system, and the other gasification units can be used as evaporators of the compression heat pump system. The compression heat pump system can transfer heat from the gasification units used as evaporators to the gasification units used as condensers, thereby melting the ice on the surface of the gasification units used as condensers. During the ice melting process, liquefied natural gas can still be gasified, resulting in high reliability and low operating costs.

Description

Technical Field

[0001] This invention relates to the field of dual-fuel engine air supply technology, and more specifically, this invention provides a dual-fuel engine air supply system with a heat pump de-icing system and an icing detection device. Background Technology

[0002] Natural gas is a commonly used alternative fuel for diesel engines in my country, offering advantages in terms of environmental friendliness. However, gaseous natural gas occupies a large volume, making storage and transportation difficult. To address this technical issue, natural gas typically needs to be cooled and pressurized to liquefy it and stored in tanks. However, directly introducing liquefied natural gas into an engine can damage it due to liquid slugging. Therefore, a carburetor is needed to re-vaporize the liquefied natural gas back into a gaseous state and then compress it to a high-pressure state before it can be used by the engine. A carburetor is a heat exchanger that transfers heat from the outside environment to the liquefied natural gas flowing through it. The liquefied natural gas absorbs this heat and vaporizes.

[0003] There are many types of vaporizers in the existing technology. Among them, the ambient air vaporizer can directly absorb heat from the air during operation, so the operating cost is low. However, when the air temperature is low, the surface of the ambient air vaporizer is easy to freeze and cannot continue to absorb heat from the air. Therefore, the application range of the ambient air vaporizer is relatively small. Summary of the Invention

[0004] This invention primarily addresses the technical problems existing in the prior art, thereby providing a dual-fuel engine air supply system and icing detection device with multiple vaporization units, a compression heat pump system, and an icing detection device. The icing detection device can detect whether ice has formed on the surface of the vaporization unit, and the heat pump system can de-ice the icy vaporization unit during the operation of the air supply system. This system has high reliability and low operating costs.

[0005] The present invention solves the technical problems existing in the prior art through the following technical solution:

[0006] A dual-fuel engine gas supply system with a heat pump de-icing system includes a vaporizer, a flow control valve, and a compression device. The vaporizer includes a liquefied natural gas (LNG) inlet and a gaseous natural gas outlet. The LNG inlet is connected to an LNG storage tank and receives LNG from the tank. The LNG absorbs heat from the outside through the vaporizer, becomes gaseous, and is discharged through the gaseous natural gas outlet. The gaseous natural gas outlet is connected to the inlet of the compression device via the flow control valve. The vaporizer includes at least two vaporization units. The dual-fuel engine gas supply system with a heat pump de-icing system also includes an inlet buffer container and an exhaust buffer container. The LNG inlet is located on the inlet buffer container, and the gaseous natural gas outlet is located on the exhaust buffer container.

[0007] The gasification unit includes an inner cylinder, an outer cylinder, and a heat medium cavity arranged between the inner cylinder and the outer cylinder;

[0008] The lower end of the inner cylinder is in fluid communication with the liquid inlet buffer container, and the upper end of the inner cylinder is in fluid communication with the venting buffer container.

[0009] The upper part of the heat medium cavity is provided with an upper connection port, and the lower part of the heat medium cavity is provided with a lower connection port;

[0010] The dual-fuel engine air supply system with heat pump de-icing system further includes a heat pump system for de-icing. The heat pump system includes a compressor, an exhaust pipe, an intake pipe, a connecting pipe, a three-way selector valve, and a throttle valve. The heat pump system is filled with a heat medium for transferring heat. The number of the three-way selector valve and the number of the throttle valve are equal to the number of the vaporization unit.

[0011] The compressor includes an air intake port and an air exhaust port, wherein the air exhaust port is connected to the exhaust pipe and the air intake port is connected to the air intake pipe.

[0012] The three-way selector valve includes a first port, a second port, and a third port. The three-way selector valve can selectively connect the first port and the second port or connect the first port and the third port.

[0013] The first interface is connected to the upper connection port, the second interface is connected to the exhaust pipe, and the third interface is connected to the intake pipe.

[0014] The lower connection port is connected to one end of the throttle valve, and the other end of the throttle valve is connected to the connecting pipe.

[0015] As a preferred technical solution of the present invention, the dual-fuel engine air supply system with heat pump de-icing system further includes an icing detection device. Each of the two or more gasification units is provided with at least one icing detection device, which is located at the lower part of the gasification unit. The icing detection device can detect whether the surface of the gasification unit is iced and can send a signal to start de-icing and a signal to end de-icing. The icing detection device connected to each gasification unit and the three-way selector valve are connected by a signal.

[0016] When the icing detection device on a gasification unit sends a signal to start de-icing, the first port on the three-way selector valve on the gasification unit is connected to the second port and disconnected from the third port.

[0017] When the icing detection device on a gasification unit sends a signal to end de-icing, the first port on the three-way selector valve of the gasification unit is disconnected from the second port and connected to the third port.

[0018] As a more preferred technical solution of the present invention, the lower end of the inner cylinder is in fluid communication with one end of a valve, and the other end of the valve is in fluid communication with the liquid inlet buffer container. The inner cylinder and the liquid inlet buffer container form a controllable fluid flow connection structure through the valve. When the valve is open, the lower end of the inner cylinder is in fluid communication with the liquid inlet buffer container, and when the valve is closed, the lower end of the inner cylinder is fluidly disconnected from the liquid inlet buffer container.

[0019] Icing detection devices and valve signal connections are connected to each gasification unit;

[0020] When the icing detection device on a gasification unit sends a signal to start de-icing, the valve on the gasification unit closes.

[0021] When the icing detection device on a gasification unit sends a signal to end de-icing, the valve on the gasification unit opens.

[0022] As a preferred technical solution of the present invention, when the icing detection device detects icing on the surface of the vaporization unit, it can delay for a preset time period T1 and then issue a signal to start de-icing; when the icing detection device detects that the surface of the vaporization unit is not iced, it can delay for a preset time period T2 and then issue a signal to end de-icing.

[0023] As a preferred technical solution of the present invention, both the preset time period T1 and the preset time period T2 are 10 minutes.

[0024] As a preferred technical solution of the present invention, the outer surface of the outer cylinder is provided with a plurality of ribs for enhancing heat transfer.

[0025] An icing detection device includes a first power connection terminal and a second power connection terminal. The icing detection device also includes a detection unit, a signal transmission unit, a power-on delay relay, and a power-off delay relay.

[0026] The energized delay relay includes a first excitation coil and an energized delay normally open contact switch;

[0027] The power-off delay relay includes a second excitation coil and a power-off delay normally open contact switch;

[0028] The two ends of the detection unit connected in series with the first excitation coil are electrically connected to the first power supply connection terminal and the second power supply connection terminal, respectively.

[0029] The two ends of the second excitation coil connected in series with the normally open energized delay contact switch are electrically connected to the first power supply connection terminal and the second power supply connection terminal, respectively.

[0030] The two ends of the power-off delay normally open contact switch connected in series with the signal transmitting unit are electrically connected to the first power connection terminal and the second power connection terminal, respectively.

[0031] The detection unit includes a first wire and a second wire, with one end of the first wire positioned close to one end of the second wire.

[0032] When liquid water is present between one end of the first wire and one end of the second wire, the first wire and the second wire can conduct electricity through the water between their ends, thereby enabling the detection unit to connect its electrical circuit. At this time, the first excitation coil is energized, and the normally open energized delay contact switch closes after a preset time period T2, which energizes the second excitation coil, thereby causing the normally open energized de-energized delay contact switch to close immediately, and the signal transmitting unit is energized and sends an end de-icing signal.

[0033] When the water between one end of the first wire and one end of the second wire freezes, the first and second wires cannot conduct electricity through the ice between their ends, thus enabling the detection unit to disconnect its electrical circuit. At this time, the first excitation coil is de-energized, and the normally open energized delay contact switch immediately opens, causing the second excitation coil to lose power. Consequently, the normally open energized delay contact switch opens after a preset time period T1. The de-energization of the signal transmitting unit indicates that the detection unit has detected an icing signal and should begin de-icing.

[0034] As a preferred technical solution of the present invention, the signal transmitting unit is a closing excitation coil.

[0035] The advantages of the dual-fuel engine air supply system with heat pump de-icing system and icing detection device of the present invention are: it has multiple vaporization units, a compression heat pump system and an icing detection device. The icing detection device can detect whether ice has formed on the surface of the vaporization unit. The heat pump system can de-ice the vaporization unit that has formed ice during the operation of the air supply system. It has high reliability and low operating cost. Attached Figure Description

[0036] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0037] Figure 1 This is a schematic diagram of the air-temperature vaporizer with a heat pump de-icing system according to the present invention.

[0038] Figure 2 This is a cross-sectional view of the gasification unit of the present invention;

[0039] Figure 3 This is a schematic diagram of the heat pump system in the ambient air vaporizer with a heat pump de-icing system of the present invention.

[0040] Figure 4 This is a circuit diagram of the icing detection device of the present invention;

[0041] in:

[0042] 1. Vaporizer; 11. Liquefied natural gas inlet; 12. Gaseous natural gas outlet; 13. Vaporization unit; 131. Inner cylinder; 132. Outer cylinder; 133. Heat medium chamber; 1331. Upper connection port; 1332. Lower connection port; 134. Ribs; 14. Liquid inlet buffer container; 15. Exhaust buffer container;

[0043] 2. Flow control valve;

[0044] 3. Compression device;

[0045] 4. Heat pump system; 41. Compressor; 411. Inlet; 412. Outlet; 42. Outlet pipe; 43. Inlet pipe; 44. Connecting pipe; 45. Three-way selector valve; 451. First port; 452. Second port; 453. Third port; 46. Throttling valve;

[0046] 5. Icing detection device; 51. First power connection terminal; 52. Second power connection terminal; 53. Detection unit; 531. First wire; 532. Second wire; 54. Signal transmitting unit; 55. Power-on delay relay; 551. First excitation coil; 552. Power-on delay normally open contact switch; 56. Power-off delay relay; 561. Second excitation coil; 562. Power-off delay normally open contact switch;

[0047] 6. Valves. Implementation

[0048] The preferred embodiments of the present invention will be described in detail below so that the advantages and features of the present invention can be more easily understood by those skilled in the art, thereby making a clearer and more explicit definition of the scope of protection of the present invention.

[0049] The advantages of the dual-fuel engine air supply system with heat pump de-icing system and icing detection device of the present invention are: it has multiple vaporization units, a compression heat pump system and an icing detection device. The icing detection device can detect whether ice has formed on the surface of the vaporization unit. The heat pump system can de-ice the vaporization unit that has formed ice during the operation of the air supply system. It has high reliability and low operating cost.

[0050] like Figure 1 As shown, a dual-fuel engine gas supply system with a heat pump de-icing system includes a vaporizer 1, a flow control valve 2, and a compression device 3. The vaporizer 1 includes a liquefied natural gas (LNG) inlet 11 and a gaseous natural gas outlet 12. The LNG inlet 11 is used to connect to a LNG storage tank and receive LNG from the LNG storage tank. The LNG absorbs heat from the outside through the vaporizer 1 and becomes gaseous, and is discharged through the gaseous natural gas outlet 12. The gaseous natural gas outlet 12 is connected to the air inlet of the compression device 3 through the flow control valve 2. The vaporizer 1 includes at least two vaporization units 13. The dual-fuel engine gas supply system with a heat pump de-icing system also includes an inlet buffer container 14 and an exhaust buffer container 15. The LNG inlet 11 is disposed on the inlet buffer container 14, and the gaseous natural gas outlet 12 is disposed on the exhaust buffer container 15.

[0051] like Figure 2 As shown, the gasification unit 13 includes an inner cylinder 131, an outer cylinder 132, a heat transfer medium cavity 133 arranged between the inner cylinder 131 and the outer cylinder 132, and ribs 134 arranged on the outer surface of the outer cylinder 132 for enhancing heat transfer. Figure 1(The rib 134 is not shown in the diagram). The lower end of the inner cylinder 131 is in fluid communication with the liquid inlet buffer container 14, and the upper end of the inner cylinder 131 is in fluid communication with the exhaust buffer container 15. The inner cylinder 131 is used for natural gas flow. After the liquid natural gas enters the liquid inlet buffer container 14, it flows into the inner cylinder 131 from the lower end. When the liquid natural gas flows through the inner cylinder 131, it absorbs heat from the outer cylinder 132 through the convection heat transfer and radiation of the heat medium in the heat medium cavity 133 and becomes gaseous natural gas. It then flows upward along the inner cylinder 131 and enters the exhaust buffer container 15. Finally, it is discharged from the gaseous natural gas outlet 12. Then, it flows through the flow control valve 2 and is controlled by the flow control valve 2 to enter the compression device 3. The gaseous natural gas is compressed to a suitable pressure in the compression device 3 and then discharged into the engine.

[0052] like Figure 1 , Figure 2 As shown, the upper part of the heat medium cavity 133 is provided with an upper connection port 1331, and the lower part of the heat medium cavity 133 is provided with a lower connection port 1332; this structure allows the heat medium to flow in the heat medium cavity 133 and to transfer heat with the inner cylinder 131 and the outer cylinder 132.

[0053] like Figure 3 As shown, the dual-fuel engine air supply system with heat pump de-icing system also includes a heat pump system 4 for de-icing. The heat pump system 4 includes a compressor 41, an exhaust pipe 42, an intake pipe 43, a connecting pipe 44, a three-way selector valve 45, and a throttle valve 46. The heat pump system 4 is filled with a heat medium for transferring heat. The number of three-way selector valves 45 and the number of throttle valves 46 are equal to the number of vaporization units 13.

[0054] like Figure 3 As shown, the compressor 41 includes an intake port 411 and an exhaust port 412. The exhaust port 412 is connected to the exhaust pipe 42, and the intake port 411 is connected to the intake pipe 43. The pressure at the exhaust port 412 of the compressor 41 is higher, and therefore the pressure in the exhaust pipe 42 is also higher; the pressure at the exhaust port 412 of the compressor 41 is lower, and therefore the pressure in the intake pipe 43 is also lower.

[0055] The three-way selector valve 45 includes a first port 451, a second port 452 and a third port 453. The three-way selector valve 45 can selectively connect the first port 451 and the second port 452 or connect the first port 451 and the third port 453.

[0056] The first interface 451 is connected to the upper connection port 1331, the second interface 452 is connected to the exhaust pipe 42, and the third interface 453 is connected to the intake pipe 43.

[0057] The lower connection port 1332 is connected to one end of the throttle valve 46, and the other end of the throttle valve 46 is connected to the connecting pipe 44.

[0058] like Figure 3 As shown, when the first port 451 and the second port 452 of the three-way selector valve 45 connected to the upper connection port 1331 of a vaporization unit 13 are connected, that is, when the upper connection port 1331 of the vaporization unit 13 is connected to the exhaust pipe 42, the high-temperature and high-pressure heat medium vapor discharged from the exhaust port 412 of the compressor 41 will flow through the heat medium chamber 133 of the vaporization unit 13 and release heat to the inner cylinder 131 and the outer cylinder 132 of the vaporization unit 13. If there is ice on the surface of the outer cylinder 132, the heat released by the high-temperature and high-pressure heat medium vapor will melt the ice on the surface of the outer cylinder 132. After the heat medium releases heat, it will liquefy into a liquid state. At this time, the vaporization unit 13 is used as a condenser.

[0059] like Figure 3 As shown, when the first port 451 and the third port 453 of the three-way selector valve 45 connected to the upper connection port 1331 of a vaporization unit 13 are connected, that is, when the upper connection port 1331 of the vaporization unit 13 is connected to the suction pipe 43, the pressure in the heat medium chamber 133 of the vaporization unit 13 is low. If there is liquid heat medium in the heat medium chamber 133 of the vaporization unit 13, the liquid heat medium will quickly vaporize under low pressure and absorb heat from the inner cylinder 131 and the outer cylinder 132 of the vaporization unit 13 and vaporize into a gaseous state. At this time, the vaporization unit 13 is used as an evaporator.

[0060] The three-way selector valve 45 can also be set so that when the first port 451 of a vaporization unit 13 is neither connected to the second port 452 nor the third port 453, that is, the upper connection port 1331 of the vaporization unit 13 is neither connected to the exhaust pipe 42 nor the intake pipe 43, the vaporization unit 13 is not connected to the heat pump system 4.

[0061] Since part of the vaporization unit 13 is used as a high-pressure condenser and the other part is used as a low-pressure evaporator, there is a pressure difference between the condenser and the evaporator. Therefore, the heat medium will continuously flow from the heat medium chamber 133 of the vaporization unit 13, which is the condenser, to the throttling valve 46 and the connecting pipe 44 connected to its lower connection port 1332, and then through the lower connection port 1332 of the vaporization unit 13, which is the evaporator, and finally enter its heat medium chamber 133. During the process of flowing through the throttling valve 46, the high-temperature and high-pressure liquid heat medium will be throttled into a low-temperature and low-pressure heat medium. The heat medium continuously releases heat in the condenser and continuously absorbs heat in the evaporator, thereby realizing the transfer of heat from low temperature to high temperature. The liquid heat medium continuously absorbs heat and vaporizes in the evaporator and finally returns to the suction port 411 of the compressor 41, and is then compressed again by the compressor 41 into a high-temperature and high-pressure heat medium. This cycle continues, continuously migrating heat from a low temperature to a high temperature.

[0062] Combination Figure 3 As can be seen from the above three paragraphs, each vaporization unit 13 is connected to the heat pump system 4 with the same structure. Therefore, any vaporization unit 13 can be used as the condenser of the heat pump system 4, and any other multiple (at least one) vaporization units 13 can be used as the evaporator of the heat pump system 4. Therefore, when any vaporization unit 13 is covered with ice, it can be used as the condenser of the heat pump system 4, thereby using the heat released by the condenser of the heat pump system 4 to melt the ice on the surface of the vaporization unit 13.

[0063] To detect whether ice has formed on the surface of the vaporization unit 13, an icing detection unit 53 can be installed at the bottom of each vaporization unit 13. Because the surface temperature of the vaporization unit 13 is low, when it absorbs heat from the air, water vapor in the air always condenses into water droplets on the surface of the vaporization unit 13 first. These droplets then gather into streams under gravity and flow downwards. During this downward flow, they continue to absorb heat from the vaporization unit 13 and eventually condense into ice. Therefore, the icing phenomenon always starts from the bottom of the vaporization unit 13 and gradually spreads upwards. As soon as icing occurs at the bottom of the vaporization unit 13, melting begins until the ice is completely melted, which basically ensures that the ice on the surface of the vaporization unit 13 is completely melted. This icing detection unit 53... 3. It can detect whether the surface of the vaporization unit 13 is icy and can send a signal to start de-icing and a signal to end de-icing; the icing detection unit 53 and the three-way selector valve 45 connected to each vaporization unit 13 are connected by a signal; when the icing detection unit 53 on a vaporization unit 13 sends a signal to start de-icing, the first port 451 and the second port 452 on the three-way selector valve 45 on the vaporization unit 13 are connected and the first port 451 and the third port 453 are disconnected; when the icing detection unit 53 on a vaporization unit 13 sends a signal to end de-icing, the first port 451 and the second port 452 on the three-way selector valve 45 on the vaporization unit 13 are disconnected and the first port 451 and the third port 453 are connected. The icing detection unit 53 can control whether the corresponding vaporization unit 13 is connected to the exhaust pipe 42 or the intake pipe 43 by controlling the flow channel opened by the three-way selector valve 45. In other words, the icing detection unit 53 can control whether the corresponding vaporization unit 13 is used as a condenser or an evaporator of the heat pump system 4. When the icing detection unit 53 detects ice on the surface of the vaporization unit 13, it controls the vaporization unit 13 to be used as a condenser of the heat pump system 4, which can melt the ice on the surface of the corresponding vaporization unit 13. As long as one vaporization unit 13 is used as an evaporator in the heat pump system 4, it can provide heat to other vaporization units 13. However, if there are too many vaporization units 13 used as condensers and too few used as evaporators, the condensation temperature will be too low, resulting in a slow ice melting rate. In some cases, the condensation temperature may even be below the freezing point, making it impossible to melt ice normally. To solve this technical problem, a controller can be installed in the heat pump system 4. This controller can detect the number of vaporization units 13 currently used as condensers and the temperature of the heat medium in their heat medium chamber 133. When the temperature is too low, for example, below 10 degrees Celsius, the three-way selector valve 45 on the vaporization unit 13 used as an evaporator can be controlled so that the vaporization unit 13 cannot be used as a condenser, even if there is ice on its surface.Alternatively, the controller can be used to limit the use of only one vaporization unit 13 as a condenser without detecting the temperature of the heat medium in its heat medium chamber 133. This method can melt the ice on the surface of the vaporization unit 13 used as a condenser in the fastest way.

[0064] When a gasification unit 13 is used as a condenser, liquefied natural gas can continue to flow through its inner cylinder 131. However, during gasification, the liquefied natural gas absorbs a significant amount of heat from the heat medium chamber 133, resulting in the heat medium in the heat medium chamber 133 of the gasification unit 13 only transferring a small amount of heat to the outer cylinder 132. This causes the ice-melting speed of the gasification unit 13 to be too slow. Therefore, the flow of liquefied natural gas in the inner cylinder 131 of the gasification unit 13 can be cut off through the scheme described in the following paragraph. When the gasification unit 13 is used as a condenser, most of the heat released by the condenser is transferred to the outer cylinder 132, and then to the ice layer on the surface of the outer cylinder 132. This scheme can further improve the ice-melting speed.

[0065] The lower end of the inner cylinder 131 is fluidly connected to one end of a valve 6, and the other end of the valve 6 is fluidly connected to the liquid inlet buffer container 14. The inner cylinder 131 and the liquid inlet buffer container 14 form a controllable fluid flow connection structure through the valve 6. When the valve 6 is open, the lower end of the inner cylinder 131 is fluidly connected to the liquid inlet buffer container 14; when the valve 6 is closed, the lower end of the inner cylinder 131 is fluidly disconnected from the liquid inlet buffer container 14. An icing detection unit 53 connected to each vaporization unit 13 and a valve 6 are connected by a signal. When an icing detection unit 53 on a vaporization unit 13 sends a signal to start de-icing, the valve 6 on that vaporization unit 13 is closed; when an icing detection unit 53 on a vaporization unit 13 sends a signal to end de-icing, the valve 6 on that vaporization unit 13 is opened.

[0066] In the technical solution disclosed in this invention, the ice on the outside of the outer cylinder 132 of the melting and vaporization unit 13 is transferred from the heat medium cavity 133 located inside the outer cylinder 132. Therefore, the ice naturally melts from the inside out. The icing detection unit 53 is installed on the outside of the outer cylinder 132. Thus, the icing detection unit 53 will send a signal indicating that the ice layer has melted only after the ice near the icing detection unit 53 melts. This causes the three-way selector valve 45 to operate frequently, and the surface of the vaporization unit 13 is always covered by ice. This invention solves this technical problem through the following technical solution:

[0067] When the icing detection unit 53 detects ice formation on the surface of the vaporization unit 13, it can delay for a preset time period T1 before issuing a signal to start de-icing. When the icing detection unit 53 detects that the surface of the vaporization unit 13 is not icy, it can delay for a preset time period T2 before issuing a signal to end de-icing. Both the preset time period T1 and the preset time period T2 are 10 minutes. In other embodiments, the preset time periods T1 and T2 can also be other durations, such as five minutes, fifteen minutes, or other durations, in order to ensure that the ice layer melts completely and to avoid wear on the three-way selector valve 45 due to frequent operation.

[0068] like Figure 4 As shown, the present invention also discloses an icing detection device 5, including a first power connection terminal 51, a second power connection terminal 52, an icing detection unit 53, a signal transmitting unit 54, a power-on delay relay 55, and a power-off delay relay 56. In use, the first power connection terminal 51 and the second power connection terminal 52 are connected to the two poles of a power source to supply power to the entire icing detection device 5. The icing detection unit 53 is placed in the area to be detected, and the icing detection unit 53 can transmit a start de-icing signal and a stop de-icing signal to the outside via the signal transmitting unit 54.

[0069] The energized time-delay relay 55 includes a first excitation coil 551 and an energized time-delay normally open contact switch 552. When the first excitation coil 551 is de-energized, the energized time-delay normally open contact switch 552 remains open. When energized, the first excitation coil 551 can send an energizing excitation signal to the energized time-delay normally open contact switch 552, and the energized time-delay normally open contact switch 552 closes after a delay time T2 upon receiving the energizing excitation signal. When de-energized, the first excitation coil 551 can send a de-energizing excitation signal to the energized time-delay normally open contact switch 552, and the energized time-delay normally open contact switch 552 immediately opens upon receiving the de-energizing excitation signal.

[0070] The power-off delay relay 56 includes a second excitation coil 561 and a power-off delay normally open contact switch 562. When the second excitation coil 561 is de-energized, the power-off delay normally open contact switch 562 remains open. When the second excitation coil 561 is energized, it can send an energizing excitation signal to the power-off delay normally open contact switch 562, and the power-off delay normally open contact switch 562 closes immediately after receiving the energizing excitation signal. When the first excitation coil 551 is de-energized, it can send a power-off excitation signal to the power-off delay normally open contact switch 562, and the power-off delay normally open contact switch 562 opens after a delay time T1 after receiving the power-off excitation signal.

[0071] The two ends of the icing detection unit 53 connected in series with the first excitation coil 551 are electrically connected to the first power connection terminal 51 and the second power connection terminal 52, respectively.

[0072] The two ends of the second excitation coil 561 connected in series with the normally open contact switch 552 with the energization delay are respectively electrically connected to the first power connection terminal 51 and the second power connection terminal 52.

[0073] The two ends of the normally open contact switch 562 with the signal transmitting unit 54 connected in series are electrically connected to the first power connection terminal 51 and the second power connection terminal 52, respectively.

[0074] The icing detection unit 53 includes a first wire 531 and a second wire 532, with one end of the first wire 531 arranged close to one end of the second wire 532.

[0075] When there is liquid water between one end of the first wire 531 and one end of the second wire 532, the first wire 531 and the second wire 532 can conduct electricity through the water between their ends, thereby enabling the icing detection unit 53 to connect its electrical circuit. At this time, the first excitation coil 551 is energized, and the normally open contact switch 552 with power-on delay is closed after a preset time period T2, which energizes the second excitation coil 561, thereby causing the normally open contact switch 562 with power-off delay to close immediately, and the signal transmitting unit 54 is energized and sends an end de-icing signal.

[0076] When the water between one end of the first wire 531 and one end of the second wire 532 freezes, the first wire 531 and the second wire 532 cannot conduct electricity through the ice between their ends, thus enabling the icing detection unit 53 to disconnect its electrical circuit. At this time, the first excitation coil 551 is de-energized, and the normally open energized delay contact switch 552 immediately opens, causing the second excitation coil 561 to be de-energized. Consequently, the normally open energized delay contact switch 562 opens after a preset time period T1. The de-energization of the signal transmitting unit 54 indicates that the icing detection unit 53 has detected an icing signal and should begin de-icing.

[0077] The signal transmitting unit 54 is a closing excitation coil. The three-way selector valve 45 of the present invention can be equipped with an electromagnetic control structure. When the closing excitation coil sends a closing signal, the three-way selector valve 45 can connect its first interface 451 to the second interface 452; when the closing excitation coil does not send a closing signal, the three-way selector valve 45 can connect its first interface 451 to the third interface 453; the three-way selector valve 45 can also be controlled by the controller of the heat pump system 4 and not connected to the heat pump system.

[0078] The above are merely some of the design ideas for the embodiments of the present invention. Where the system allows, the present invention can be extended to simultaneously connect more functional modules, thereby maximizing its functionality.

[0079] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions conceived without inventive effort should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A dual-fuel engine gas supply system with a heat pump de-icing system, comprising a vaporizer (1), a flow control valve (2), and a compression device (3), wherein the vaporizer (1) comprises a liquefied natural gas inlet (11) and a gaseous natural gas outlet (12), the liquefied natural gas inlet (11) is used to connect to a liquefied natural gas storage tank and receive liquefied natural gas from the liquefied natural gas storage tank, the liquefied natural gas absorbs heat from the outside through the vaporizer (1) and becomes gaseous, and is discharged through the gaseous natural gas outlet (12), the gaseous natural gas outlet (12) is connected to the air inlet of the compression device (3) through the flow control valve (2), the vaporizer (1) comprises at least two vaporization units (13), characterized in that: The dual-fuel engine gas supply system with heat pump de-icing system further includes an inlet buffer container (14) and an exhaust buffer container (15). The liquefied natural gas inlet (11) is located on the inlet buffer container (14), and the gaseous natural gas outlet (12) is located on the exhaust buffer container (15). The gasification unit (13) includes an inner cylinder (131), an outer cylinder (132), and a heat medium cavity (133) arranged between the inner cylinder (131) and the outer cylinder (132). The lower end of the inner cylinder (131) is in fluid communication with the liquid inlet buffer container (14), and the upper end of the inner cylinder (131) is in fluid communication with the exhaust buffer container (15). The upper part of the heat medium cavity (133) is provided with an upper connection port (1331), and the lower part of the heat medium cavity (133) is provided with a lower connection port (1332). The dual-fuel engine air supply system with heat pump de-icing system also includes a heat pump system (4) for de-icing. The heat pump system (4) includes a compressor (41), an exhaust pipe (42), an intake pipe (43), a connecting pipe (44), a three-way selector valve (45), and a throttle valve (46). The heat pump system (4) is filled with a heat medium for transferring heat. The number of the three-way selector valve (45) and the number of the throttle valve (46) are equal to the number of the vaporization unit (13). The compressor (41) includes an air intake (411) and an air exhaust (412), wherein the air exhaust (412) is connected to the exhaust pipe (42) and the air intake (411) is connected to the air intake pipe (43); The three-way selector valve (45) includes a first port (451), a second port (452) and a third port (453). The three-way selector valve (45) can selectively connect the first port (451) and the second port (452) or connect the first port (451) and the third port (453). The first interface (451) is connected to the upper connection port (1331), the second interface (452) is connected to the exhaust pipe (42), and the third interface (453) is connected to the intake pipe (43). The lower connection port (1332) is connected to one end of the throttle valve (46), and the other end of the throttle valve (46) is connected to the connecting pipe (44).

2. The dual-fuel engine air supply system with heat pump de-icing system according to claim 1, characterized in that: The dual-fuel engine air supply system with heat pump de-icing system also includes an icing detection unit (53). Each of the two or more vaporization units (13) is provided with at least one icing detection unit (53). The icing detection unit (53) is located at the lower part of the vaporization unit (13). The icing detection unit (53) can detect whether the surface of the vaporization unit (13) is iced and can send a signal to start de-icing and a signal to end de-icing. The icing detection unit (53) connected to each vaporization unit (13) and the three-way selector valve (45) are connected by a signal. When the icing detection unit (53) on a vaporization unit (13) sends a signal to start de-icing, the first port (451) and the second port (452) on the three-way selector valve (45) on the vaporization unit (13) are connected, and the first port (451) and the third port (453) are disconnected. When the icing detection unit (53) on a vaporization unit (13) sends a signal to end de-icing, the first port (451) and the second port (452) on the three-way selector valve (45) on the vaporization unit (13) are disconnected, and the first port (451) and the third port (453) are connected.

3. The dual-fuel engine air supply system with a heat pump de-icing system according to claim 2, characterized in that: The lower end of the inner cylinder (131) is in fluid communication with one end of a valve (6), and the other end of the valve (6) is in fluid communication with the liquid inlet buffer container (14). The inner cylinder (131) and the liquid inlet buffer container (14) form a controllable fluid flow connection structure through the valve (6). When the valve (6) is open, the lower end of the inner cylinder (131) is in fluid communication with the liquid inlet buffer container (14). When the valve (6) is closed, the lower end of the inner cylinder (131) is fluidly disconnected from the liquid inlet buffer container (14). The icing detection unit (53) and valve (6) are connected to each gasification unit (13) for signal connection; When the icing detection unit (53) on a gasification unit (13) sends a signal to start de-icing, the valve (6) on the gasification unit (13) is closed; When the icing detection unit (53) on a vaporization unit (13) sends a signal to end de-icing, the valve (6) on the vaporization unit (13) opens.

4. The dual-fuel engine air supply system with a heat pump de-icing system according to claim 2, characterized in that: When the icing detection unit (53) detects that the surface of the vaporization unit (13) is icy, it can delay for a preset time period T1 and then issue a signal to start de-icing. When the icing detection unit (53) detects that the surface of the vaporization unit (13) is not icy, it can delay for a preset time period T2 and then issue a signal to end de-icing.

5. The dual-fuel engine air supply system with a heat pump de-icing system according to claim 4, characterized in that: Both the preset time period T1 and the preset time period T2 are 10 minutes.

6. The dual-fuel engine air supply system with a heat pump de-icing system according to claim 1, characterized in that: The outer surface of the outer cylinder (132) is provided with a plurality of fins (134) for enhancing heat transfer.

7. The dual-fuel engine air supply system with a heat pump de-icing system according to claim 1, characterized in that: The dual-fuel engine air supply system with heat pump de-icing system also includes an icing detection device, which includes a first power connection terminal (51), a second power connection terminal (52), an icing detection unit (53), a signal transmission unit (54), a power-on delay relay (55), and a power-off delay relay (56). The energized delay relay (55) includes a first excitation coil (551) and an energized delay normally open contact switch (552). The power-off delay relay (56) includes a second excitation coil (561) and a power-off delay normally open contact switch (562). The two ends of the icing detection unit (53) connected in series with the first excitation coil (551) are electrically connected to the first power connection terminal (51) and the second power connection terminal (52), respectively. The two ends of the second excitation coil (561) and the normally open contact switch (552) connected in series are electrically connected to the first power supply connection terminal (51) and the second power supply connection terminal (52), respectively. The two ends of the normally open contact switch (562) with the power-off delay and the signal transmitting unit (54) connected in series are electrically connected to the first power connection terminal (51) and the second power connection terminal (52), respectively. The icing detection unit (53) includes a first wire (531) and a second wire (532), with one end of the first wire (531) arranged close to one end of the second wire (532); When there is liquid water between one end of the first wire (531) and one end of the second wire (532), the first wire (531) and the second wire (532) can conduct electricity through the water between their ends, thereby enabling the icing detection unit (53) to connect its electrical circuit. At this time, the first excitation coil (551) is energized, and the energizing delay normally open contact switch (552) closes after a preset time period T2, thereby energizing the second excitation coil (561), thereby causing the de-energizing delay normally open contact switch (562) to close immediately, and the signal transmitting unit (54) to be energized and send an end de-icing signal. When the water between one end of the first wire (531) and one end of the second wire (532) freezes, the first wire (531) and the second wire (532) cannot conduct electricity through the ice between their ends, thereby enabling the icing detection unit (53) to disconnect its electrical circuit. At this time, the first excitation coil (551) is de-energized, and the normally open contact switch (552) with power-on delay immediately opens, causing the second excitation coil (561) to lose power. Consequently, the normally open contact switch (562) with power-off delay opens after a preset time period T1. The signal transmitting unit (54) loses power, indicating that the icing detection unit (53) has detected an icing signal and should begin de-icing.

8. The dual-fuel engine air supply system with a heat pump de-icing system according to claim 7, characterized in that: The signal transmitting unit (54) is a closing excitation coil.

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