Methanol dual fuel generator return line double wall pipe annular area leak prevention safety system

Abstract

A kind of methanol dual-fuel generator return pipeline double-wall pipe annular area leak-proof safety system, including pressure reducing valve, manual stop valve, bleeder module, stop check valve, methanol dual-fuel generator, stop check valve, bleeder valve, safety valve, manual stop valve, balance valve, terminal bleeder valve.The pressure reducing valve is used to reduce 13bar nitrogen to 2bar, make 2bar nitrogen fill annular area, the bleeder module is used to connect the connection between annular area and double-wall pipe inner tube.Manual stop valve is used to manually purge the methanol leaked in annular area, terminal bleeder valve is used to access the methanol liquid remaining in annular area into portable bleeder tank.The present application can quickly solve the problem of methanol generator double-wall pipe annular area leak in safety area, adopt closed measures to remove methanol in annular area, realize quickly emptying methanol in annular area, with simple design, easy operation, safety explosion-proof characteristics.

Description

TECHNICAL FIELD

[0001] The present application relates to a methanol dual-fuel generator, and more particularly to a safety arrangement of the methanol dual-fuel generator. BACKGROUND

[0002] During the shipping operation, there is no methanol leakage in the annular area of the double-wall pipe under the normal working condition of the generator, but in the design process, if there is methanol leakage, it is a problem that needs to be solved, that is, the safety hazard of methanol leakage in the annular area of the safety zone needs to be solved, so that it can meet the requirements of the specification and quickly eliminate the hidden danger.

[0003] The prior art does not eliminate such hidden dangers, and there is no method to solve this problem. The nitrogen generating device of the prior art is only used for purging treatment in the initial use or cleaning stage, but does not involve disposal in the leakage stage, and there is no requirement and design for such leakage disposal in the technical field.

[0004] According to the specification requirements, in the device arrangement scheme of the methanol project, the methanol daily use cabinet for supplying methanol is arranged above the methanol dual-fuel generator. SUMMARY

[0005] The present application solves the problem of methanol leakage in the annular area of the double-wall pipe in the dangerous area, especially for the case that methanol leaks into the annular area of the return pipeline, and designs a solution for the annular area to quickly eliminate the hidden danger and ensure the safety of navigation.

[0006] In order to achieve the above purpose, the present application provides a methanol dual-fuel generator return pipeline double-wall pipe annular area anti-leakage safety system, wherein the methanol dual-fuel generator is provided with a return pipeline in the form of a double-wall pipe; the inner pipe of the return pipeline is used for returning methanol; the outer pipe of the return pipeline is connected to a nitrogen supply end, and nitrogen is filled in;

[0007] The return pipeline is connected to the nitrogen supply end at the low point position by setting a first manual stop valve C2.

[0008] The return pipeline is connected to the nitrogen outlet of the methanol relief cabinet at the high point position by setting a second manual stop valve C9.

[0009] In a preferred mode, a liquid level detection switch or a methanol detection sensor is further arranged at the lowest position of the outer pipe of the return pipeline double-wall pipe.

[0010] In a preferred mode, a first stop check valve is arranged at the rear of the medium flow direction on the pipeline where the first manual stop valve C2 is arranged.

[0011] In a preferred mode, the pipeline in which the first manual cut-off valve C2 is arranged in parallel is also provided with a pressure reducing pipeline connected to the nitrogen supply end, and the pressure reducing pipeline is sequentially provided with a pressure reducing valve B1 and a second cut-off check valve in the medium flow direction.

[0012] In a preferred mode, a safety valve C8 is arranged in parallel with the second manual cut-off valve C9.

[0013] In a preferred mode, a discharge pipeline is arranged by arranging a terminal discharge valve C11; the discharge pipeline is sequentially provided with a low-end discharge valve C7 and a balance valve C10 connected to the return pipeline at a low point in the medium flow direction.

[0014] In a preferred mode, the discharge pipeline is also connected to the rear end pipeline of the second manual cut-off valve C9 and the safety valve C8.

[0015] In a preferred mode, the return pipeline is connected to the pipeline of the nitrogen supply end at a low point, and a third cut-off check valve C6 is arranged near the low point.

[0016] The present application can be operated in a safe area, and methanol will not enter the atmospheric environment of the safe area, ensuring the safety of the operator; the present application sets up a discharge module, and the methanol leaked in the annular area is blown into a methanol discharge cabinet (suitable for the case of large methanol leakage) by using 13 bar nitrogen; the discharge module is set up, and 13 bar nitrogen is used for preliminary purging, and then the balance valve is used to discharge the pressure in the annular area to normal pressure; finally, the terminal discharge valve is used to remove the remaining methanol by using a portable discharge tank, thereby finally solving the leakage problem of the annular area.

[0017] The present application can quickly solve the problem of leakage of the annular area of the methanol generator double-wall pipe in the safe area, mainly aims at the leakage of the annular area of the methanol return pipeline, adopts airtight measures to remove the methanol in the annular area, realizes rapid emptying of the methanol in the annular area, and has the characteristics of simple design, convenient operation and safety and explosion prevention. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 is a schematic diagram of the whole system layout of the methanol dual-fuel generator;

[0019] Figure 2 is Figure 1 is a schematic diagram of the return pipeline system layout of the present application;

[0020] Figure 3 is a system schematic diagram without a leakage solution;

[0021] In the figure, A1: pressure reducing valve; A2: manual stop valve of methanol supply pipeline; A3: relief module; A4: stop check valve of methanol supply pipeline; A5: methanol dual-fuel generator; A6: stop check valve of double-wall pipe annular area; A7: safety valve; A8: relief valve; B1: pressure reducing valve; B2: manual stop valve of methanol bypass pipeline; B4: stop check valve of methanol bypass pipeline; B6: stop check valve of double-wall pipe annular area; B7: relief valve; C2: first manual stop valve; C4: stop check valve of methanol return pipeline; C6: third stop check valve; C7: relief valve; C8: safety valve; C9: second manual stop valve; C10: balance valve; C11: terminal relief valve; f1: cabin safety area; f2: nitrogen inlet; f3: methanol inlet; f4: double-wall pipe; f5: nitrogen outlet; f6: methanol return. DETAILED DESCRIPTION

[0022] The present application is a methanol dual-fuel generator return pipeline double-wall pipe annular area anti-leakage safety system, as shown in Figure 1 and Figure 2 , comprising B1-pressure reducing valve, C2-first manual stop valve, A3-relief module, C4-stop check valve of methanol return pipeline, A5-methanol dual-fuel generator, C6-third stop check valve, C7-relief valve, C8-safety valve, C9-second manual stop valve, C10-balance valve, and C11-terminal relief valve.

[0023] Further comprising A1-pressure reducing valve, A2-manual stop valve of methanol supply pipeline, A4-stop check valve of methanol supply pipeline, A6-stop check valve of double-wall pipe annular area, A7-safety valve, and A8-relief valve. B2-manual stop valve of methanol bypass pipeline, B4-stop check valve of methanol bypass pipeline, A5-methanol dual-fuel generator, B6-stop check valve of double-wall pipe annular area, and B7-relief valve.

[0024] Comparison Figure 3 It can be seen that the improvement of the present application is that, aiming at the return pipeline double-wall pipe annular area, i.e. the outer pipe area of the double-wall pipe, a nitrogen purging system is arranged to realize purging work of methanol leakage.

[0025] Specifically, the pressure reducing valve B1 is used to reduce 13 bar nitrogen to 2 bar, so that 2 bar nitrogen fills the annular zone, and the annular zone forms an oxygen-free environment, which ensures that even if methanol leaks into the annular zone, it does not have the conditions to burn or explode. The first manual stop valve C2 is used to manually purge the annular zone of methanol into the relief tank, the relief module A3 is used to connect the annular zone and the inner tube of the double-wall pipe, the third stop check valve C6 is arranged in the relief module A3, and the third stop check valve C6 is arranged in the relief module A3. The third stop check valve C6 is arranged in the relief module A3, which prevents nitrogen and methanol from flowing back. The methanol dual-fuel generator A5 is located in the engine room safety zone. The relief valve C7 is used to release the small amount of methanol residue that may exist, the safety valve C8 is used to prevent the annular zone of the double-wall pipe from overpressure, the second manual stop valve C9 is used to manually purge the leaked methanol in the annular zone, and the balance valve C10 is used to balance the pressure of the annular zone and the relief tank. The terminal relief valve C11 is used to connect the residual methanol liquid in the annular zone to the portable relief tank.

[0026] The operation steps of the present application when methanol leaks in the return pipeline are as follows:

[0027] When methanol of the methanol dual-fuel generator leaks into the annular zone of the engine return pipeline, first, open the first manual stop valve C2 and the second manual stop valve C9, and use 13 bar nitrogen to blow the methanol in the annular zone into the methanol relief tank (suitable for the case where the amount of methanol leakage is large). This step solves the leakage of the methanol return pipeline in the annular zone; the nitrogen outlet is connected to the methanol relief tank.

[0028] Check whether the liquid level switch of the relief module A3 returns to normal. The liquid level switch is located at the lowest point of the relief module, so as long as there is residual methanol, it will be detected by the liquid level switch. If the liquid level in the annular zone is high and continues to alarm, continue to repeat step 1 until the liquid level switch in the annular zone of the relief module A3 returns to normal.

[0029] Close the first manual stop valve C2. At this time, the nitrogen in the annular zone gradually enters the inner tube of the double-wall pipe through the third stop check valve C6 in the relief module A3. The one-way setting value of the third stop check valve C6 is 2 bar, and nitrogen can only enter the inner tube through C6 from the annular zone, but any liquid or gas in the inner tube cannot enter the annular zone through C6. When the nitrogen is reduced to 2 bar, the annular zone continuously forms a 2 bar nitrogen sealed inert gas safety environment.

[0030] The pressure reducing valve B1 is used to reduce 13 bar nitrogen to 2 bar, which is used for the nitrogen sealing of the annular zone during the daily operation of the generator. The stop check valve C4 of the methanol return pipeline is used to prevent nitrogen backflow and methanol backflow that may exist when methanol leaks in the inner tube.

[0031] Open the relief valve C7 and the balance valve C10 to make the pressure of the annular zone consistent with the pressure of the relief tank, so as to reach atmospheric pressure.

[0032] Finally open the terminal relief valve C11, using a portable relief tank to remove residual methanol;

[0033] Carefully check the cause of the leak, and restore the generator operation after the cause is removed.

[0034] In summary, the features of the cleaning process are as follows:

[0035] Due to the annular area of the methanol return line, the actual layout and pipe diameter are limited, and it is not possible to achieve downward purging from the top to make methanol enter the inner tube of the double-wall pipe. Only nitrogen purging can be performed from bottom to top. In the actual purging process, when methanol is purged from the annular area to the inner tube, bubbling phenomenon will occur, and the leaked methanol cannot be blown into the inner tube. Therefore, for the methanol return line annular area leakage, the method of blowing from the annular area to the inner tube cannot be used.

[0036] For the methanol remaining in the annular area that cannot be emptied by gravity, 13 bar nitrogen is used to purge the methanol in the annular area to the relief cabinet through the bypass valve (suitable for large methanol leakage situations).

[0037] For the small amount of methanol remaining in the annular area that cannot be emptied, the communication valve is used to reduce the pressure, keeping the same nitrogen sealing pressure as the relief cabinet 0.2 bar, to ensure the safety of the operator, and then the remaining methanol is emptied through a portable tank container.

[0038] In Figure 1 , Figure 2 , Figure 3 , f1 is the engine room safety zone; f2 is the nitrogen inlet; f3 is the methanol inlet; f4 is the double-wall pipe; f5 is the nitrogen outlet; and f6 is the methanol return.

[0039] The above description is only a preferred embodiment of the present application, but the protection scope of the present application is not limited thereto. Any skilled person in the art can make equivalent replacements or changes to the technical solution and the inventive concept of the present application within the technical scope disclosed by the present application, which should be covered within the protection scope of the present application.

Claims

1. A leak-proof safety system for the annular zone of a methanol dual-fuel generator return pipeline, characterized in that, The methanol dual-fuel generator is equipped with a return pipeline in the form of a double-walled pipe; the inner pipe of the return pipeline is used to return methanol; the outer pipe of the return pipeline is connected to the nitrogen supply end, and then nitrogen is introduced. The return pipeline is connected to the nitrogen supply end at the low point by a first manual shut-off valve C2. The return pipeline is connected to the nitrogen outlet of the methanol venting cabinet at the high point via a second manual shut-off valve C9. A liquid level detection switch or a methanol detection sensor is also installed at the lowest position of the outer pipe of the double-walled return pipeline. The pipeline connected in parallel to the first manual shut-off valve C2 is also provided with a pressure-reducing pipeline connected to the nitrogen supply end. The pressure-reducing pipeline is provided with a pressure-reducing valve B1 and a second shut-off check valve in sequence according to the medium flow direction. The discharge pipeline is configured by setting the terminal discharge valve C11; The discharge pipeline is sequentially equipped with a low-end discharge valve C7 and a balance valve C10 connected to the return pipeline at the lowest point according to the medium flow direction. The return pipeline is connected to the nitrogen supply end at the low point, and a third shut-off check valve C6 is installed near the low point.

2. The methanol dual-fuel generator return pipeline double-walled pipe annular zone leak prevention safety system according to claim 1, characterized in that, A first shut-off check valve is installed on the pipeline where the first manual shut-off valve C2 is located at the rear of the medium flow direction.

3. The methanol dual-fuel generator return pipeline double-walled pipe annular zone leak prevention safety system according to claim 1, characterized in that, A safety valve C8 is connected in parallel to the second manual shut-off valve C9.

4. The methanol dual-fuel generator return pipeline double-walled pipe annular zone leak prevention safety system according to claim 1, characterized in that, The discharge pipeline is also connected to the rear end pipelines of the second manual shut-off valve C9 and the safety valve C8.

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