LPG buffer release tank and control system

Abstract

The present invention discloses an LPG buffer release tank and a control system, which belongs to the technical field of ship LPG power pipeline safety control, and is divided into a buffer release tank part and an LPG control part. The buffer release tank part includes a release valve group and a tank body, and the release valve group is connected with the tank body of the buffer release tank. A discharge pipe is fixedly installed at the highest point of the dome of the tank body of the buffer release tank, and the discharge outlet of the discharge pipe is connected to the air-permeable mast on the LPG ship. A nitrogen blow-off pipe is fixedly installed on one side of the tank body, and a one-way valve is fixedly installed on the nitrogen blow-off pipe. The LPG buffer release tank and the control system collect the liquid remaining when the LPG is not completely vaporized by setting a buffer tank, and the released LPG is first vaporized by the buffer release tank, and then discharged to the air-permeable mast for discharge, so as to avoid the damage of the ship and the crew to the liquid splashing, and the relevant equipment is displayed and remotely controlled by the fuel control unit, so as to realize the multifunctional remote automatic control of the buffer tank.

Description

Technical Field

[0001] The invention belongs to the technical field of safety control of LPG power pipelines of ships, and in particular relates to an LPG buffer release tank and a control system. Background Art

[0002] On LPG (liquefied petroleum gas) ships, the common safety release pipeline is directly released from the release valve group to the vent mast, which is used when the LPG (liquefied petroleum gas) power transmission pipe needs to be released urgently. However, in the prior art, this common design currently has the following problems and disadvantages:

[0003] (1) Without a buffer tank, the vaporization is incomplete during release, and the residual LPG liquid is easily splashed out through the vent mast, causing damage to the ship and crew.

[0004] (2) Without HC (hydrocarbon) content detection and nitrogen purge, it is impossible to know the explosive mixture in the ventilated mast and it is impossible to clear it.

[0005] In order to overcome the shortcoming that the common release pipe only has a vent mast, a buffer release tank and a control system are provided between the release valve group and the vent mast. Summary of the invention

[0006] In view of the deficiencies in the prior art, the present invention provides an LPG buffer release tank and a control system to solve the problems raised in the above background technology.

[0007] To achieve the above object, the present invention provides the following technical solutions: an LPG buffer release tank and a control system, which are divided into a buffer release tank part and an LPG control part, the buffer release tank part includes a release valve group and a tank body, the release valve group is connected with the tank body of the buffer release tank, a discharge pipe is fixedly installed at the highest point of the dome of the tank body of the buffer release tank, the discharge port of the discharge pipe is connected to the air-permeable mast on the LPG ship, a nitrogen blow-off pipe is fixedly installed on one side of the tank body, and a one-way valve is fixedly installed on the nitrogen blow-off pipe;

[0008] The LPG control part includes a fuel control unit, a main engine control unit and multiple groups of control signal lines. The fuel control unit and the main engine control unit are respectively used for emergency discharge and shutdown of the release valve group and the control main engine of the LPG ship. The fuel control unit is also electrically connected to a hydrocarbon detector, a first liquid level switch, a second liquid level switch and a heating facility through the control signal line, and displays and remotely controls the above components.

[0009] To further optimize the technical solution, a discharge pipe valve is provided below the bottom of the tank body of the buffer tank, and the discharge pipe valve is used to discharge possible impurities and water.

[0010] To further optimize the technical solution, a grounding facility is provided on one side of the bottom of the buffer tank, and the grounding facility is used to eliminate static electricity in the buffer tank to avoid detonation of mixed gas in the buffer tank during emergency discharge.

[0011] To further optimize the technical solution, the first liquid level switch and the second liquid level switch are arranged in sequence from top to bottom on one side of the inner part of the tank body of the buffer tank, the first liquid level switch is a high-high level alarm, and the second liquid level switch is a high level alarm.

[0012] To further optimize the technical solution, the hydrocarbon detector is arranged on the surface of the tank body of the buffer tank to monitor the concentration of the explosive mixed gas in the buffer tank in real time. A sampling tube valve is arranged between the hydrocarbon detector and the tank body of the buffer tank. The sampling tube valve is in a normally open state and is closed when the hydrocarbon detector is maintained and calibrated.

[0013] To further optimize the technical solution, the heating coil in the heating facility is arranged inside the tank body of the buffer tank to heat the LPG to accelerate its vaporization.

[0014] To further optimize the technical solution, the LPG buffer release tank and control system, during emergency release, the release valve group opens, LPG enters the tank body of the buffer tank, the tank body discharge port of the buffer tank is at normal pressure, and LPG vaporizes under normal pressure after entering. Part of the liquid drips to the bottom of the tank body before vaporization, and LPG expands rapidly after vaporization, and the vaporized product is discharged from the discharge pipe.

[0015] To further optimize the technical solution, the LPG buffer release tank and control system, if the LPG liquid pressure accumulates excessively and triggers the high-high level alarm of the first liquid level switch, the fuel control unit and the main engine control unit will close the emergency discharge release valve group and the control main engine of the LPG ship, so as to prevent the excessive liquid in the tank from overflowing from the discharge pipe and causing accidents that cause injury to the ship and personnel.

[0016] To further optimize the technical solution, the fuel control unit is used to realize multifunctional remote automatic control of the buffer tank when displaying and remotely controlling the hydrocarbon detector, the first liquid level switch, the second liquid level switch and the heating facility through the control signal line, thereby avoiding the need for people to go to the site for operation.

[0017] Compared with the prior art, the present invention provides an LPG buffer release tank and a control system, which have the following beneficial effects:

[0018] 1. The LPG buffer release tank and control system collects the residual liquid when LPG is not completely vaporized by setting a buffer tank. The released LPG is first vaporized in the buffer release tank and then discharged to the vent mast for discharge, avoiding liquid splashing to damage the ship and crew.

[0019] 2. The LPG buffer release tank and control system monitors the concentration of explosive mixed gas in the buffer tank in real time by setting up a hydrocarbon detector to improve the safety of emissions.

[0020] 3. The LPG buffer release tank and control system have a nitrogen blowing function by setting a nitrogen blowing pipe to remove LPG vapor and control the concentration of the explosive mixed gas within 25% LEL to ensure the safety inside the tank.

[0021] 4. The LPG buffer release tank and control system are equipped with double liquid level switches. When the high level alarm of LPG accumulated liquid is triggered, the heating facilities are turned on to accelerate its vaporization to avoid excessive accumulation. When the high level alarm is triggered, the main engine and the emergency discharge release valve group are closed to prevent excessive liquid from overflowing the discharge pipe and causing injuries to ships and personnel, thereby further improving the safety of LPG release.

[0022] 5. The LPG buffer release tank and control system are equipped with a fuel control unit, which displays and remotely controls related equipment to achieve multifunctional remote automatic control of the buffer tank, avoiding the need for on-site operation and enhancing safety. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic diagram of the structure of an LPG buffer release tank and a control system proposed by the present invention;

[0024] Figure 2 It is a structural schematic diagram of a common safety release pipeline in the prior art.

[0025] In the figure: 1. Release valve group; 2. Discharge pipe; 3. Nitrogen blow-off pipe; 4. Drain pipe valve; 5. Check valve; 6. Sampling tube valve; 7. Hydrocarbon detector; 8. Heating facility; 9. Grounding facility; 10. Tank body; 11. First liquid level switch; 12. Second liquid level switch; 13. Fuel control unit; 14. Host control unit; 15. Control signal line. DETAILED DESCRIPTION

[0026] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] Embodiment 1:

[0028] See also Figure 1, an LPG buffer release tank and control system, which are divided into a buffer release tank part and an LPG control part, the buffer release tank part includes a release valve group 1 and a tank body 10, the release valve group 1 is connected with the tank body 10 of the buffer release tank, a discharge pipe 2 is fixedly installed at the highest point of the dome of the tank body 10 of the buffer release tank, the discharge outlet of the discharge pipe 2 is connected to the air-permeable mast on the LPG ship, a nitrogen blow-off pipe 3 is fixedly installed on one side of the tank body 10, and a one-way valve 5 is fixedly installed on the nitrogen blow-off pipe 3;

[0029] The LPG control part includes a fuel control unit 13, a main engine control unit 14 and multiple groups of control signal lines 15. The fuel control unit 13 and the main engine control unit 14 are respectively used for emergency discharge and shutdown of the release valve group 1 and the control main engine of the LPG ship. The fuel control unit 13 is also electrically connected to the hydrocarbon detector 7, the first liquid level switch 11, the second liquid level switch 12 and the heating facility 8 through the control signal line 15, and displays and remotely controls the above components.

[0030] Specifically, a discharge pipe valve 4 is provided below the bottom of the tank body 10 of the buffer tank, and the discharge pipe valve 4 is used to discharge possible impurities and water.

[0031] Specifically, a grounding facility 9 is provided on one side of the bottom of the tank body 10 of the buffer tank, and the grounding facility 9 is used to eliminate static electricity of the tank body 10 of the buffer tank to avoid detonating the mixed gas in the tank body 10 of the buffer tank during emergency discharge.

[0032] Specifically, the first liquid level switch 11 and the second liquid level switch 12 are sequentially arranged on one side of the inner part of the tank body 10 of the buffer tank from top to bottom. The first liquid level switch 11 is a high-high level alarm, and the second liquid level switch 12 is a high level alarm.

[0033] Specifically, the hydrocarbon detector 7 is arranged on the surface of the tank body 10 of the buffer tank, and is used to monitor the concentration of the explosive mixed gas in the buffer tank in real time. A sampling tube valve 6 is arranged between the hydrocarbon detector 7 and the tank body 10 of the buffer tank. The sampling tube valve 6 is in a normally open state and is closed when the hydrocarbon detector 7 is maintained and calibrated.

[0034] Specifically, the heating coil in the heating facility 8 is arranged inside the tank body 10 of the buffer tank, and is used to heat the LPG to accelerate its vaporization.

[0035] Specifically, in the LPG buffer release tank and control system, if the LPG liquid pressure accumulates excessively and triggers the high-high level alarm of the first liquid level switch 11, the fuel control unit 13 and the main engine control unit 14 will close the emergency discharge release valve group 1 and the control main engine of the LPG ship to prevent the excessive liquid in the tank from overflowing from the discharge pipe 2 and causing injuries to the ship and personnel.

[0036] Specifically, when the fuel control unit 13 displays and remotely controls the hydrocarbon detector 7, the first liquid level switch 11, the second liquid level switch 12 and the heating facility 8 through the control signal line 15, it is used to realize multifunctional remote automatic control of the buffer tank, avoiding the need for people to go to the site for operation.

[0037] Embodiment 2:

[0038] See also Figure 2 , the common safety release pipeline is to release directly from the release valve group to the vent mast, which is used when the LPG power transmission pipe needs to be released urgently, resulting in incomplete vaporization during release, and it is easy to splash out the residual LPG liquid through the vent mast, which will cause harm to the ship and the crew; and there is no HC (hydrocarbon) content detection and nitrogen blowing, so it is impossible to know the explosive mixture in the vent mast, and it is impossible to clear it. Using an LPG buffer release tank and control system described in Example 1, during emergency release, the release valve group 1 is opened, and LPG enters the tank body 10 of the buffer tank. The discharge port of the tank body 10 of the buffer tank is at normal pressure. After entering, LPG is vaporized at normal pressure. Part of the liquid does not have time to vaporize and drips to the bottom of the tank body 10. After LPG vaporizes, it expands rapidly, and the vaporized product is discharged from the discharge pipe 2. After the liquid dripping to the bottom of the tank is also vaporized and discharged, it can be blown away by the nitrogen blowing pipe 3. Finally, the nitrogen and HC mixture in the tank should be controlled to be less than 25% LEL explosion concentration to ensure the safety of the tank. A one-way valve 5 is installed on the nitrogen blow-off pipe 3 to prevent LPG vapor from flowing back into the nitrogen pipe. The nitrogen pipe should extend to the bottom of the tank. Since the specific gravity of nitrogen is lower than that of gaseous propane (the main vapor component of LPG), it should be blown off from the bottom. When the release flow is too large, LPG will not have time to vaporize, and the accumulated liquid level will continue to rise, which will trigger the second liquid level switch 12 of the high-level alarm, and turn on the heating facility 8. The heating coil of the heating facility 8 accelerates the vaporization of LPG by heating it. If the LPG liquid pressure is excessive and triggers the high-high level (LAHH) alarm of the first liquid level switch 11, the fuel control unit 13 and the main engine control unit 14 will close the emergency discharge release valve group 1 and the main engine to prevent the excessive liquid in the tank from overflowing the discharge pipe 2, causing an accident of injury to the ship and personnel.

[0039] The beneficial effects of the present invention are:

[0040] 1. The LPG buffer release tank and control system collects the residual liquid when LPG is not completely vaporized by setting a buffer tank. The released LPG is first vaporized in the buffer release tank and then discharged to the vent mast for discharge, avoiding liquid splashing to damage the ship and crew.

[0041] 2. The LPG buffer release tank and control system monitors the concentration of explosive mixed gas in the buffer tank in real time by setting up a hydrocarbon detector to improve the safety of emissions.

[0042] 3. The LPG buffer release tank and control system have a nitrogen blowing function by setting a nitrogen blowing pipe to remove LPG vapor and control the concentration of the explosive mixed gas within 25% LEL to ensure the safety inside the tank.

[0043] 4. The LPG buffer release tank and control system are equipped with double liquid level switches. When the high level alarm of LPG accumulated liquid is triggered, the heating facilities are turned on to accelerate its vaporization to avoid excessive accumulation. When the high level alarm is triggered, the main engine and the emergency discharge release valve group are closed to prevent excessive liquid from overflowing the discharge pipe and causing injuries to ships and personnel, thereby further improving the safety of LPG release.

[0044] 5. The LPG buffer release tank and control system are equipped with a fuel control unit, which displays and remotely controls related equipment to achieve multifunctional remote automatic control of the buffer tank, avoiding the need for on-site operation and enhancing safety.

[0045] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0046] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An LPG buffer release tank and control system, comprising a buffer release tank part and an LPG control part, characterized in that: The buffer release tank part comprises a release valve group (1) and a tank body (10), wherein the release valve group (1) is connected to the tank body (10) of the buffer release tank, a discharge pipe (2) is fixedly installed at the highest point of the dome of the tank body (10) of the buffer release tank, and the discharge outlet of the discharge pipe (2) is connected to the air permeability mast on the LPG ship, and a nitrogen blow-off pipe (3) is fixedly installed on one side of the tank body (10), and a check valve (5) is fixedly installed on the nitrogen blow-off pipe (3); the LPG control part comprises a fuel control unit (13), a main engine control unit (14) and a plurality of A control signal line (15) is connected to the fuel control unit (13) and the main engine control unit (14) for emergency discharge and shutdown of the release valve group (1) and the main engine of the LPG ship, respectively; the fuel control unit (13) is also electrically connected to a hydrocarbon detector (7), a first liquid level switch (11), a second liquid level switch (12) and a heating facility (8) through the control signal line (15) and displays and remotely controls the hydrocarbon detector (7), the first liquid level switch (11), the second liquid level switch (12) and the heating facility (8); The invention is characterized in that when the release flow is too large, the LPG has no time to vaporize, and the accumulated liquid level continues to rise, which will trigger the second liquid level switch (12) of the high-level alarm, and turn on the heating facility (8). The heating coil of the heating facility (8) accelerates the vaporization of the LPG by heating the LPG; if the LPG liquid pressure is excessive and triggers the high-high-level (LAHH) alarm of the first liquid level switch (11), the fuel control unit (13) and the main engine control unit (14) will close the emergency discharge release valve group (1) and the main engine to prevent the excessive liquid in the tank from overflowing the discharge pipe (2) and causing an accident of injury to the ship and personnel.

2. The LPG buffer release tank and control system according to claim 1, characterized in that: A discharge pipe valve (4) is provided below the bottom of the tank body (10) of the buffer release tank, and the discharge pipe valve (4) is used to discharge possible impurities and water.

3. The LPG buffer release tank and control system according to claim 1, characterized in that: A grounding facility (9) is provided on one side of the bottom of the tank body (10) of the buffer release tank, and the grounding facility (9) is used to eliminate static electricity in the tank body (10) of the buffer release tank to prevent the explosive mixed gas in the tank body (10) of the buffer release tank from detonating during emergency discharge.

4. The LPG buffer release tank and control system according to claim 1, characterized in that: The first liquid level switch (11) and the second liquid level switch (12) are arranged in sequence from top to bottom on one side of the interior of the tank body (10) of the buffer release tank, the first liquid level switch (11) being a high-high level alarm, and the second liquid level switch (12) being a high-level alarm.

5. The LPG buffer release tank and control system according to claim 1, characterized in that: The hydrocarbon detector (7) is arranged on the surface of the tank body (10) of the buffer release tank and is used to monitor the concentration of the explosive mixed gas in the buffer release tank in real time. A sampling tube valve (6) is arranged between the hydrocarbon detector (7) and the tank body (10) of the buffer release tank. The sampling tube valve (6) is in a normally open state and is closed when the hydrocarbon detector (7) is maintained and calibrated.

6. The LPG buffer release tank and control system according to claim 1, characterized in that: The heating coil in the heating facility (8) is arranged inside the tank body (10) of the buffer release tank and is used to heat the LPG to accelerate its vaporization.

7. The LPG buffer release tank and control system according to claim 1, characterized in that: In the LPG buffer release tank and control system, during emergency release, the release valve group (1) is opened, and LPG enters the tank body (10) of the buffer release tank. The discharge port of the tank body (10) of the buffer release tank is at normal pressure. After entering, LPG is vaporized under normal pressure, and part of the liquid drips to the bottom of the tank body (10) before being vaporized. After LPG is vaporized, it expands rapidly, and the vaporized product is discharged from the discharge pipe (2).

8. The LPG buffer release tank and control system according to claim 4, characterized in that: The LPG buffer release tank and control system are such that, if the LPG liquid pressure is excessive and triggers the high-high level alarm of the first liquid level switch (11), the fuel control unit (13) and the main engine control unit (14) will close the emergency discharge release valve group (1) and the control main engine of the LPG ship, so as to prevent the liquid in the tank from excessively overflowing the discharge pipe (2) and causing an accident that may injure the ship or personnel.

9. The LPG buffer release tank and control system according to claim 1, characterized in that: When the fuel control unit (13) displays and remotely controls the hydrocarbon detector (7), the first liquid level switch (11), the second liquid level switch (12) and the heating facility (8) through the control signal line (15), it is used to realize multifunctional remote automatic control of the buffer release tank, avoiding the need for people to go to the site for operation.

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