Fuel leakage recovery processing device of dual-fuel engine

Abstract

The utility model relates to a fuel leakage recovery processing device of a dual-fuel engine, which comprises a valve group mechanism communicated with a buffer cavity, the valve group mechanism comprises a valve body, a sliding groove with the diameter smaller than that of a valve cavity is arranged in the middle section of the valve cavity in the valve body, and a valve block is arranged in the sliding groove. A plurality of first side grooves and second side grooves which are staggered in the length direction are formed in the side wall of the valve block at intervals, and the valve block is kept balanced through elastic pieces at the two ends. According to the device, the detection pipe and the recovery pipe are used for detecting tiny leakage and recovering a large amount of leakage respectively, for tiny leakage, the bidirectional detection precision is improved through the first side groove and the second side groove which are staggered, tiny pressure difference can push the elastic piece to slide, the flow meter can detect the flow and the flowing direction, and the detection precision is improved. And for a large amount of leakage, if the high-precision flow meter cannot meet the flow requirement, large-flow recovery is carried out by conducting the recovery pipe and the booster pump, and the gas is refilled into the double-layer pipe to be recycled.

Description

Technical Field

[0001] The utility model belongs to the technical field of dual-fuel engines, and particularly relates to a fuel leakage recovery and treatment device for a dual-fuel engine. Background Art

[0002] A dual-fuel engine is an engine that can use both fuel oil and natural gas (or other gaseous fuels such as liquefied petroleum gas) as fuels. This kind of engine has the ability to switch between fuel oil and gas modes, and usually is equipped with two independent fuel supply systems. One is used to supply natural gas or liquefied petroleum gas, and the other is used to supply other fuels except natural gas. The application of dual-fuel engines in the ship field is relatively common, especially on large ocean-going ships. Because it can flexibly switch fuels and adapt to the fuel supply situations in different regions, it is highly favored.

[0003] The gas fuel pipeline of the dual-fuel engine reduces the pressure of the gas in the gas storage cylinder and then transports it to the engine. For safe use, generally, a double-layer pipeline is used for transportation. A buffer cavity is formed between the outer pipe and the inner pipe, and two layers of sealing rings are arranged at the flange connection to form a buffer cavity for double protection. However, when the inner pipe or the inner sealing ring has leaked, it is difficult to accurately detect through the outer pipe. And for the slight leakage of the sealing ring at the flange connection, it is also difficult to detect according to the air concentration. It is difficult to quickly respond and give early warning. Moreover, for a large amount of leakage in a short time, there is not only the danger of explosion, but also due to the weakening of the engine air supply pressure, it causes abnormal shutdown. Summary of the Utility Model

[0004] The purpose of the utility model is to provide a fuel leakage recovery and treatment device for a dual-fuel engine to solve the above problems.

[0005] The utility model realizes the above purpose through the following technical solutions:

[0006] A fuel leakage recovery and treatment device for a dual-fuel engine, which is used to detect the air pressure leakage of the buffer cavity of the double-layer pipe and recover it, includes

[0007] A valve group mechanism communicated with the buffer cavity, which includes a valve body. In the middle section of the valve cavity in the valve body, there is a chute with a diameter smaller than that of the valve cavity. The chute divides the valve cavity into two ends, A and B. A valve block that seals and slides is arranged in the chute. A plurality of first side grooves and second side grooves that are mutually offset in the length direction are arranged at intervals on the side wall of the valve block. The valve block is kept in balance by elastic members at both ends. When in balance, the first side grooves and the second side grooves are respectively communicated with the two ends, A and B, of the valve cavity, and the valve cavity at end A is communicated with the buffer cavity;

[0008] A recovery mechanism, which includes a normally closed recovery pipe for recovering the fuel leaked from the A-end valve chamber, and a booster pump for pumping the fuel back to the double-layer pipe. It also includes an inert gas storage tank, which is connected to the B-end valve chamber through a detection pipe, and a flow meter is arranged in the detection pipe.

[0009] As a further optimized solution of the present utility model, the air pressure of the inert gas storage tank is higher than the atmospheric pressure and lower than the working pressure of the double-layer pipe. The inert gas storage tank pushes open the valve block through the air pressure to conduct the second side groove, so that the buffer chamber is filled with inert gas and maintains the same air pressure. In this solution, by filling the buffer chamber with inert gas and making the air pressure of the inert gas higher than the atmospheric pressure and lower than the working pressure of the double-layer pipe, the air leakage on both the inner and outer sides of the buffer chamber can be detected, achieving the purpose of early warning. And the air pressure generated by the inert gas reduces the pressure difference between the two sides of the inner pipe of the double-layer pipe, and the gradient pressure reduces the pipeline leakage risk.

[0010] As a further optimized solution of the present utility model, the recovery mechanism further includes a fuel storage tank, which is used to temporarily store the fuel pumped by the booster pump. And a one-way valve is arranged at the outlet of the fuel storage tank and connected to the double-layer pipe, and a one-way valve is arranged at the inlet and connected to the booster pump. By setting the fuel storage tank to receive the fuel pumped by the booster pump, and pumping it into the double-layer pipe again after re-boosting, it can prevent a large amount of leakage from causing insufficient fuel supply to the engine and resulting in abnormal shutdown.

[0011] As a further optimized solution of the present utility model, the inert gas storage tank is provided with a pressure sensor, and inert gas is replenished into it or pressure is relieved through the booster pump to keep the pressure constant. The inert gas storage tank keeps the pressure constant and detects the leakage direction through the flow meter. For example, when there is a slight leakage in the inner pipe, the pressure in the A-end valve chamber increases, and the pressure difference makes the valve block slide towards the B-end valve chamber and conduct the first side groove. Then the flow meter can continuously detect the flow rate, and the leakage position and direction can be known. When the outer pipe leaks, the sliding direction of the slider is opposite, the second side groove is conducted, and the flow meter can also know the leakage direction.

[0012] As a further optimized solution of the present utility model, the inert gas storage tank and the fuel storage tank share a two-way booster pump. The recovery pipe is connected to the booster pump after passing through the inert gas storage tank, and a one-way valve for inhaling inert gas is also arranged at the opposite end of the booster pump and the inert gas storage tank. This solution shares the same two-way booster pump, reducing the equipment cost and achieving the function of two-way boosting. Or a set of booster pump can be used separately for the inert gas storage tank, and then the recovery pipe is directly connected to the booster pump of the fuel storage tank without passing through the inert gas storage tank.

[0013] As a further optimization solution of the present utility model, the recovery pipe is kept normally closed by a valve member. Among them, the valve member is connected to the valve block and slides correspondingly with the A-end valve cavity. The recovery pipe communicates with the side wall of the A-end valve cavity and is blocked by the valve member. Through holes are provided on the surface of the valve member for guiding fuel to the first side groove and the second side groove when there is a slight fuel leakage. When the valve member is completely pushed by the pressure difference to the side end of the chute, the recovery pipe communicates with the A-end valve cavity. In this solution, the opening condition of the recovery pipe is directly triggered by the valve block. Among them, the length of the first side groove is slightly longer than the length of the chute. When there is a slight fuel leakage, a slight pressure difference generated at both ends of the valve block can conduct the first side groove. If the pressure difference does not continue to increase, the elastic member keeps the valve block balanced, and the first side groove remains conducting. The flowmeter can detect the slight leakage. If the leakage is serious, the pressure at both ends of the valve member is too high, and the elastic member is insufficient to maintain the balance. Then, the valve member presses against the side end of the chute, and the first side groove is no longer conducting. The whole of the valve member and the valve block acts as a one-way valve. The seriously leaked fuel passes through the recovery pipe. The flow rate of the recovery pipe is greater than that of the detection pipe, and there is no need to consider the detection accuracy. It can be recycled in large quantities through a booster pump.

[0014] The beneficial effects of the present utility model are as follows:

[0015] In the present utility model, the detection pipe and the recovery pipe are respectively used for detecting slight leakage and recovering a large amount of leakage. For slight leakage, the two-way detection accuracy is greatly improved through the mutually offset first side groove and the second side groove. A slight pressure difference can push the elastic member to slide, and the flowmeter can detect the flow rate and the flow direction, so as to judge the inner leakage and the outward leakage. For a large amount of leakage, the high-precision flowmeter cannot meet the flow rate. Then, the recovery pipe is conducted and a booster pump is used for large-flow recovery, and it is recharged into the double-layer pipe for recycling. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is the overall structural schematic diagram of the present utility model;

[0017] Figure 2 is the schematic diagram of the valve group mechanism of the present utility model;

[0018] Figure 3 is the Figure 1 amplified view of the structure of part A in the present utility model;

[0019] Figure 4 is the schematic diagram of the first side groove and the second side groove of the present utility model;

[0020] Figure 5 is the first functional schematic diagram of the valve group mechanism of the present utility model;

[0021] Figure 6 is the second functional schematic diagram of the valve group mechanism of the present utility model;

[0022] Figure 7 It is the third functional schematic diagram of the valve group mechanism of the present utility model;

[0023] In the figure: 1. Valve group mechanism; 11. Valve body; 12. Valve cavity; 13. Slide groove; 14. Valve block; 15. Valve component; 16. Through hole; 17. First side groove; 18. Second side groove; 19. Elastic member; 2. Recovery mechanism; 21. Booster pump; 22. Fuel storage tank; 23. Inert gas storage tank; 24. Recovery pipe; 25. Detection pipe; 26. Flowmeter; 3. Double-layer pipe; 31. Outer pipe; 32. Inner pipe; 33. Flange; 34. First sealing ring; 35. Second sealing ring; 36. Buffer cavity. Specific implementation mode

[0024] The following further describes the present application in detail with reference to the accompanying drawings. It is necessary to point out here that the following specific implementation modes are only used to further illustrate the present application and cannot be understood as limiting the protection scope of the present application. Those skilled in the art can make some non-essential improvements and adjustments to the present application according to the above application content.

[0025] Embodiment 1

[0026] As Figures 1 - 7 shown, a fuel leakage recovery and treatment device for a dual-fuel engine, used to detect the air pressure leakage of the buffer cavity 36 of the double-layer pipe 3 and recover it, includes

[0027] A valve group mechanism 1 communicated with the buffer cavity 36, which includes a valve body 11. A slide groove 13 with a diameter smaller than that of the valve cavity 12 is arranged in the middle section of the valve cavity 12 in the valve body 11. The slide groove 13 divides the valve cavity 12 into two ends A and B. A valve block 14 that seals and slides is arranged in the slide groove 13. A plurality of first side grooves 17 and second side grooves 18 that are mutually offset in the length direction are arranged at intervals on the side wall of the valve block 14. The valve block 14 is kept in balance by elastic members 19 at both ends. When in balance, the first side groove 17 and the second side groove 18 are respectively communicated with the two ends AB of the valve cavity 12, and the valve cavity 12 at end A is communicated with the buffer cavity 36;

[0028] A recovery mechanism 2, which includes a normally closed recovery pipe 24 for recovering the fuel leaked from the valve cavity 12 at end A and a booster pump 21 for pumping the fuel back to the double-layer pipe 3. It also includes an inert gas storage tank 23, which is communicated with the valve cavity 12 at end B through a detection pipe 25, and a flowmeter 26 is arranged in the detection pipe 25.

[0029] As Figure 1As shown, the double-layer pipe 3 includes an inner pipe 32, an outer pipe 31, a flange 33, a first sealing ring 34, and a second sealing ring 35. A buffer cavity 36 is formed between the inner pipe 32 and the outer pipe 31, and a buffer cavity 36 is also formed between the first sealing ring 34 and the second sealing ring 35. Generally speaking, the larger the range of the flowmeter 26, the lower the relative accuracy. In this solution, the detection pipe 25 and the recovery pipe 24 are respectively used for fine leakage detection and large leakage recovery. Among them, fine leakage is further divided into outward leakage (such as the outer pipe 31 and the second sealing ring 35) and internal leakage (such as leakage of the inner pipe 32 and the first sealing ring 34). For fine leakage, in order to improve the detection accuracy, a very thin detection pipe 25 and a high-precision flowmeter 26 need to be set. By the mutually offset first side groove 17 and second side groove 18, the bidirectional detection accuracy is greatly improved. A slight pressure difference can push the elastic member 19, such as Figure 2 As shown, one end of the first side groove 17 communicates with the A-end valve cavity 12, and the other end is flush with the sliding groove 13. Only a small pressure difference can push the valve body 14 to slide, conduct the first side groove 17, and the diameter of the detection pipe 25 is small. Setting a high-precision flowmeter 26 can detect fine leakage. Vice versa, a slight reverse pressure difference can conduct the second side groove 18, and the recovery pipe 24 is used for large-flow recovery.

[0030] It should be noted that the high-precision flowmeter 26 is a prior art, and the existing flowmeter 26 can detect the flow direction. Or, two one-way flowmeters 26 are connected in parallel, and the conduction directions of the two one-way flowmeters 26 are opposite, which can also produce the same effect of detecting the direction.

[0031] The air pressure in the inert gas storage tank 23 is higher than the atmospheric pressure and lower than the working pressure of the double-layer pipe 3. The inert gas storage tank 23 pushes open the valve block 14 through the air pressure to conduct the second side groove 18, so that the buffer cavity 36 is filled with inert gas and maintains the same air pressure. In this solution, by filling the buffer cavity 36 with inert gas and making the air pressure of the inert gas higher than the atmospheric pressure and lower than the working pressure of the double-layer pipe, air leakage on both the inner and outer sides of the buffer cavity 36 can be detected, achieving the purpose of early warning. And the air pressure generated by the inert gas reduces the pressure difference on both sides of the first sealing ring 34, and the setting of the gradient pressure reduces the leakage risk.

[0032] The recovery mechanism 2 further includes a fuel storage tank 22. The fuel storage tank 22 is used to temporarily store the fuel pumped by the booster pump 21. And a one-way valve is provided at the outlet of the fuel storage tank 22 and connected to the double-layer pipe 3, and a one-way valve is provided at the inlet and connected to the booster pump 21. By setting the fuel storage tank 22 to receive the fuel pumped by the booster pump 21, after re-pressurization, it is pumped into the double-layer pipe 3 again to prevent insufficient fuel supply to the engine caused by a large amount of leakage and abnormal shutdown.

[0033] The inert gas storage tank 23 is provided with a pressure sensor, and the inert gas is added to the inside through the booster pump 21, or the pressure is released to maintain a constant pressure. The inert gas storage tank 23 maintains a constant pressure and detects the leakage direction through the flow meter 26. For example, when the inner tube 32 / the first sealing ring 34 leaks slightly, the fuel in the double-layer tube 3 enters the buffer chamber 36, which causes the pressure in the valve chamber 12 at the A end to increase. The pressure difference causes the valve block 14 to slide toward the valve chamber 12 at the B end and connects the first side groove 17. Then the flow meter 26 can continuously detect the flow rate and know the leakage position and leakage direction. When the outer tube 31 / the second sealing ring 35 leaks, the inert gas in the buffer chamber 36 is lost to the atmosphere, which causes the pressure in the valve chamber 12 at the A end to decrease. The sliding direction of the slider 14 is opposite, the second side groove 18 is connected, and the flow meter 26 can also know the leakage direction.

[0034] The recovery pipe 24 is kept normally closed by the valve member 15, wherein the valve member 15 is connected to the valve block 14 and slides correspondingly with the valve cavity 12 at the A end, the recovery pipe 24 is connected to the side wall of the valve cavity 12 at the A end and is blocked by the valve member 15, and a through hole 16 is provided on the surface of the valve member 15 for guiding the fuel to the first side groove 17 and the second side groove 18 when there is a slight leakage of fuel, and when the valve member 15 is pushed by the pressure difference to move completely to the side end of the slide groove 13, the recovery pipe 24 is connected with the valve cavity 12 at the A end. In this scheme, the opening condition of the recovery pipe 24 is directly triggered by the valve block 14, wherein the length of the first side groove 17 is slightly longer than the length of the slide groove 13, and when there is a slight leakage of fuel, the valve The slight pressure difference generated at both ends of the block 14 can conduct the first side groove 17. If the pressure difference does not continue to increase, the elastic member 19 keeps the valve block 14 balanced, the first side groove 17 continues to be connected, and the flow meter 26 can detect slight leakage. If the leakage is serious, the pressure difference at both ends of the valve member 15 is too large, and the elastic member 19 is insufficient to maintain balance, then the valve member 15 is pressed on the side end of the slide groove 13, the first side groove 17 is no longer connected, and the valve member 15 and the valve block 14 as a whole act as a one-way valve. Severely leaked fuel enters the recovery pipe 24. The flow rate of the recovery pipe 24 is much greater than that of the detection pipe 26. There is no need to consider the detection accuracy, and a large amount of recovery can be performed through the booster pump 21.

[0035] As another embodiment, the inert gas storage tank 23 and the fuel storage tank 22 share a bidirectional booster pump 21, and the recovery pipe 24 is connected to the booster pump 21 after passing through the inert gas storage tank 23. A one-way valve for inhaling inert gas is also provided at the opposite end of the booster pump 21 and the inert gas storage tank 23. This solution shares the same bidirectional booster pump 21, which can reduce equipment costs and achieve the function of bidirectional boosting. Figure 1As shown, one end of the boost pump 21 is connected to the inert gas storage tank 23, and the other end is connected to the fuel storage tank 22 and the inert gas source, and a one-way valve is respectively set. When a large amount of fuel leaks, the gas pressure in the inert gas storage tank 23 increases, and the boost pump 21 pumps the fuel into the fuel storage tank 22. When the pressure of the fuel storage tank 22 is greater than the double-layer tube 3, it can flow back to the double-layer tube 3 again. The inert gas mixed into the fuel storage tank 22 has little effect on the combustion effect. On the contrary, in order to maintain the pressure of the inert gas storage tank 23, the boost pump 21 can also suck in the inert gas to increase the pressure in the inert gas storage tank 23.

[0036] In addition, the inert gas storage tank 23 may also use a set of booster pump 21 alone, and the recovery pipe 24 is directly connected to the booster pump 21 of the fuel storage tank 22 without passing through the inert gas storage tank 23 .

[0037] The specific principles are:

[0038] First function: Detecting slight leakage of the inner tube 32 / first sealing ring 34. When the leakage occurs, the pressure of the buffer chamber 36 increases slowly, such as Figure 5 As shown, the valve block 14 slides slightly to the left, so that the first side groove 17 is turned on. Since the sliding stroke is small, the first side groove 17 can be turned on, so the ability to detect leakage is strong. The fuel enters the detection tube 25 through the through hole 16 and the second side groove 17. The flow meter 26 detects the gas flow and flow direction, and the leakage position can be determined and it can be judged that the inner tube 32 / the first sealing ring 34 is leaking.

[0039] Second function: Detecting minor leaks in the outer tube 31 / second sealing ring 35. Although the gas does not leak directly into the external environment, the risk of the second line of defense also needs to be dealt with. When the above leakage occurs, the inert gas in the buffer chamber 36 leaks into the external environment, and the gas pressure decreases. Figure 6 As shown, the valve block 14 slides slightly to the right, and the second side groove 18 is connected. Similarly, the sliding stroke is small, and a slight pressure difference caused by a small amount of leakage can be discovered immediately. The inert gas enters the detection tube 25, the second side groove 18, and the through hole 16 from the inert gas storage tank 23 into the buffer chamber 36. The flow meter 26 detects the gas flow and flow direction, and the leakage position can be determined and it can be judged that the outer tube 31 / the second sealing ring 35 is leaking.

[0040] The third function: large-scale leakage recovery and processing. When the inner tube 32 / first sealing ring 34 leaks a large amount, the pressure in the valve chamber 12 at the A end increases sharply, such as Figure 7As shown, a huge pressure difference is generated at both ends of the valve member 15. The elastic member 19 is not sufficient to keep the valve block 14 balanced. The pressure difference presses the valve member 15 against the outer end of the side groove 13, forming a one-way valve to completely close the chute 13. The leaked fuel enters the inert gas storage tank 23 through the recovery pipe 24. In order to keep the pressure constant, the inert gas storage tank 23 transfers all the increased pressure to the fuel storage tank 22. After the pressure of the fuel storage tank 22 is greater than that of the double-layer pipe 3, the fuel re-enters the double-layer pipe 3 to replenish the pressure again.

[0041] The above-described embodiments merely represent several implementation manners of the present utility model, and the description thereof is relatively specific and detailed. However, it should not be construed as a limitation to the scope of the patent of the present utility model. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present utility model, several modifications and improvements can still be made, and these all belong to the protection scope of the present utility model.

Claims

1. A fuel leakage recovery and treatment device for a dual-fuel engine, which is used to detect the air pressure leakage condition of the buffer cavity (36) of the double-layer pipe (3) and recover it, and is characterized in that: including a valve group mechanism (1) connected to a buffer chamber (36), which includes a valve body (11). In the middle section of a valve chamber (12) inside the valve body (11), a chute (13) with a diameter smaller than that of the valve chamber (12) is provided. The chute (13) divides the valve chamber (12) into two ends, A and B. A valve block (14) that slides in a sealed manner is arranged in the chute (13). A number of first side grooves (17) and second side grooves (18) that are offset from each other in the length direction are arranged at intervals on the side wall of the valve block (14). The valve block (14) is kept in balance by elastic members (19) at both ends. When in balance, the first side groove (17) and the second side groove (18) are respectively connected to the two ends, A and B, of the valve chamber (12), and the A-end valve chamber (12) is connected to the buffer chamber (36). a recovery mechanism (2), which includes a normally closed recovery pipe (24) for recovering the leaked fuel from the A-end valve chamber (12), and a booster pump (21) for pumping the fuel back to the double-layer pipe (3). It also includes an inert gas storage tank (23), which is connected to the B-end valve chamber (12) through a detection pipe (25), and a flow meter (26) is arranged in the detection pipe (25).

2. The fuel leakage recovery and treatment device for a dual-fuel engine according to claim 1, characterized in that: The air pressure in the inert gas storage tank (23) is higher than the atmospheric pressure and lower than the working pressure of the double-layer pipe (3). The inert gas storage tank (23) pushes open the valve block (14) through the air pressure to conduct the second side groove (18), so that the buffer chamber (36) is filled with inert gas and maintains the same air pressure.

3. The fuel leakage recovery and treatment device for a dual-fuel engine according to claim 1, characterized in that: The recovery mechanism (2) also includes a fuel storage tank (22), which is used to temporarily store the fuel pumped by the booster pump (21). A check valve is provided at the outlet of the fuel storage tank (22) and is connected to the double-layer pipe (3), and a check valve is provided at the inlet and is connected to the booster pump (21).

4. The fuel leakage recovery and treatment device for a dual-fuel engine according to claim 3, characterized in that: The inert gas storage tank (23) is provided with a pressure sensor, and inert gas is supplemented into it or pressure is relieved through the booster pump (21) to keep the pressure constant.

5. The fuel leakage recovery and treatment device for a dual-fuel engine according to claim 4, characterized in that: The inert gas storage tank (23) and the fuel storage tank (22) share a two-way booster pump (21). The recovery pipe (24) is connected to the booster pump (21) after passing through the inert gas storage tank (23). A check valve for inhaling inert gas is also arranged at the opposite end of the booster pump (21) and the inert gas storage tank (23).

6. The fuel leakage recovery and treatment device for a dual-fuel engine according to claim 1, characterized in that: The recovery pipe (24) is kept normally closed by a valve member (15). Among them, the valve member (15) is connected to the valve block (14) and slides correspondingly with the A-end valve chamber (12). The recovery pipe (24) is connected to the side wall of the A-end valve chamber (12) and is blocked by the valve member (15). Through holes (16) are arranged on the surface of the valve member (15) for guiding the flow to the first side groove (17) and the second side groove (18) when the fuel leaks slightly. When the valve member (15) is completely pushed by the pressure difference to move towards the side end of the chute (13), the recovery pipe (24) is connected to the A-end valve chamber (12).

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