A marine biological prevention pipe network system with a non-protected seawater pump group and a protection method

Abstract

The present invention provides a marine life prevention pipe network system and a protection method with an unprotected seawater pump group, which belongs to the field of marine petroleum engineering technology. The system comprises a pump tower and two seawater lifting pump groups arranged in the pump tower. By utilizing the long-term shutdown of the seawater lifting pump group and the mutual independence of the left and right pump towers, and by utilizing equipment such as a seawater buffer tank, a pressure reducing valve and a check valve, a full system protection function is achieved, that is, electrolyte is injected into each pipe network when the seawater lifting pump group is in operation, and electrolyte is injected into the seawater lifting pump group in reverse when the seawater lifting pump group is stopped. The system fully matches the unprotected seawater lifting pump group environment of a mobile self-elevating production platform and the characteristics and requirements of marine life prevention and control in the seawater system under long-term shutdown conditions, and has the advantages of simple process, convenient operation, economic effectiveness and safety.

Description

Technical Field

[0001] The invention belongs to the technical field of offshore petroleum engineering, and in particular relates to a marine life prevention pipe network system with a non-protected seawater pump group and a protection method. Background Art

[0002] Seawater lifting pump is a key equipment of offshore oil platform. The continuous and stable operation of the pump group is related to the normal production and fire safety of the platform.

[0003] Existing offshore oil platforms include fixed production platforms and mobile jack-up production platforms. The submerged seawater lifting pump units of fixed production platforms are placed in fixed pump protection pipes, and anti-marine biofilm electrolytic solution is injected into the pump protection pipes to protect the pump units from marine biofilm erosion. The mobile self-elevating production platform is a new type of facility developed in recent years for shallow sea marginal oil fields. Because it is equipped with wellhead facilities, the service life of the mobile self-elevating production platform in a single oil field is the same as the economic cycle of the oil field, and it cannot be regularly released for docking repairs like mobile support or processing platforms; at the same time, in order to meet the needs of platform lifting and movement, the seawater lifting pump unit of the mobile self-elevating production platform needs to be installed inside a liftable pump tower. The cramped installation space makes it impossible to install protective pipes on the pump unit, and it is impossible to close the area. The harsh wind and wave surge environment makes it impossible to implement the marine biological protection of the pump unit in the electrolyte injection method according to the conventional technical solution with protective pipes. Without the protection of protective pipes and other anti-marine biological devices for a long time, the attachment and growth rate of marine organisms cannot be effectively suppressed. Once the water inlet filter, coupling, flow channel, impeller, etc. of the seawater lifting pump unit are completely eroded by marine organisms, the pump unit will be stuck and unable to operate. In addition, because the pump unit is immersed in seawater, it is very likely to cause serious faults such as wear and locking of the pump unit bearing ring.

[0004] Currently, none of the mobile self-elevating production platforms in use are equipped with a pump group anti-marine organism system. On the one hand, due to the limited installation space of the lifting tower, the seawater lifting pump group usually needs to take into account fire protection needs, and the demand for stable operation of the pump group is even greater than that of fixed platforms; on the other hand, because most mobile self-elevating production platforms are wellhead platforms, the relatively simple production process means that the seawater system usually has no continuous users, and the pump group is in a pump-off state most of the time, which further provides an environment for marine organisms to stay and grow. According to the statistical results of the mobile self-elevating production platforms currently in service, the growth rate and failure rate of marine organisms in their seawater lifting pump groups are significantly higher than those of other types of platforms.

[0005] Therefore, there is an urgent need to develop a pipeless submerged seawater lifting pump suitable for a mobile self-elevating production platform and a marine growth protection system for its seawater system to achieve marine growth protection for its seawater lifting pump group and pipeline network. Summary of the invention

[0006] The problem to be solved by the present invention is to provide a marine life prevention pipe network system and a protection method for a mobile self-elevating production platform with a non-protected seawater pump group.

[0007] To solve the above technical problems, the technical solution adopted by the present invention is: a marine biological prevention pipe network system with a non-protected seawater pump group, comprising a pump tower, wherein two seawater lifting pump groups are arranged in the pump tower, and the two seawater lifting pump groups are respectively connected to the input end of the water lifting pipe check valve in the tower through the water lifting pipe in the tower, and the output end of the water lifting pipe check valve in the tower is connected to the first landing manual valve through the water outlet hose, and the valve plate of the water lifting pipe check valve in the tower is provided with a discharge hole, and the upper deck pipe network at the output end of the first landing manual valve is sequentially provided with a filtering electrolysis device, a second landing manual valve and a landing pipeline check valve, and the output end of the landing pipeline check valve is connected to the seawater pipe network main pipe in the cabin, and the seawater pipe network main pipe is respectively connected to the seawater buffer tank and the seawater pressure cabinet, and a domestic seawater pump is arranged between the seawater pressure cabinet and the seawater pipe network main pipe, and the output end of the seawater pressure cabinet is connected to the domestic seawater user through the domestic seawater pipe network; the domestic seawater pipe network is connected to the filtering electrolysis device through a pressure reducing valve.

[0008] Furthermore, two pump towers are provided, and the two pump towers are respectively installed on the port side and the starboard side of the jack-up production platform.

[0009] Furthermore, the seawater lifting pump group is a submerged vertical installation pump group installed in a pump tower. The suction port of the seawater lifting pump group is located at the connection part with the motor. The seawater lifting pump group has no continuous users and is in a shutdown state most of the time. The flow channels in each stage of the pump are well sealed and free of fluctuations.

[0010] Furthermore, 2 to 4 discharge holes with a diameter of 8 to 12 mm are arranged on the valve plate of the water-lifting pipe check valve in the tower. The water-lifting pipe check valve in the tower prevents most of the seawater from flowing back to the sea surface through the water-lifting pipe in the tower of another non-operating seawater lift pump group when a single seawater lift pump group is in operation. The discharge holes on the valve plate provide sufficient flow channels for the confluence of the electrolyte. At the same time, only a water volume of no more than 2 m³ / h can be discharged under pressure, and the water demand of each pipe network will not be affected.

[0011] Furthermore, the installation position of the filtering and electrolysis device is higher than the pipeline position at the pump tower end and is located at the highest point of the upper deck pipeline network.

[0012] Furthermore, the filtering electrolysis device comprises a cylinder, and infusion ports are symmetrically arranged on both sides of the cylinder, a filter basket is arranged inside the cylinder, and the filter basket is located between the two infusion ports, and a cover is arranged on the top of the cylinder, and a copper electrode and an aluminum electrode are inserted into the opening of the cover. The filter basket is a detachable structure, and the filter basket is placed on a bracket on the inner wall of the cylinder.

[0013] The present invention also provides a method for protecting a marine life-preventing pipe network system having an unprotected seawater pump group, comprising the following steps:

[0014] S1. When the seawater lifting pump group is in operation:

[0015] S11, the seawater lifting pump group draws seawater, and sends the seawater into the upper deck pipeline network through the water lifting pipe in the tower, the check valve of the water lifting pipe in the tower and the water outlet hose, and the shore pressure is about 5~7 bar; after passing through the first shore manual valve, the filter electrolysis device and the second shore manual valve, the seawater carries the electrolytic copper and aluminum liquid electrolyzed by the filter electrolysis device to push open the shore pipeline check valve and enter the seawater pipeline main in the cabin, and then enters the seawater buffer tank for storage.

[0016] Among them, the seawater is sent into the upper deck pipeline network and passes through the filtering and electrolysis device, carrying some electrolytic copper and aluminum liquid, providing preliminary protection for each pipeline network.

[0017] S12, the seawater in the seawater buffer tank is sent to the domestic seawater pump through the seawater pipe network main, and the domestic seawater pump pressurizes the seawater and sends it to the domestic seawater pipe network and domestic seawater users through the seawater pressure cabinet.

[0018] S2. When the seawater lifting pump group stops running:

[0019] Furthermore, part of the seawater in the domestic seawater network is reduced in pressure to 1 bar by a pressure reducing valve and then enters the filtration electrolysis device to participate in secondary electrolysis again, and enters the water pumping pipe in the tower through the check valve of the water pumping pipe in the tower, flows into the stopped seawater lifting pump group through the water pumping pipe in the tower, passes through the impellers and guide casings at various stages, and then flows out from the suction port of the seawater lifting pump group in the reverse direction.

[0020] Furthermore, the opening pressure of the shore pipeline check valve is 2~3bar. When the seawater lifting pump group is running, the shore pipeline check valve of 5~7bar can be opened at any time to introduce seawater into the upper deck pipeline network; when the seawater lifting pump group is not running, the low pressure of the secondary electrolyte cannot open the shore pipeline check valve, preventing most of the electrolyte from flowing back into the upper deck pipeline network, giving priority to ensuring the electrolyte demand of the pump head part of the seawater lifting pump group.

[0021] Due to the adoption of the above technical solution, the present invention has the following beneficial effects:

[0022] The present invention utilizes the long-term shutdown of the seawater lifting pump group and the independent properties of the left and right pump towers, and uses equipment such as a seawater buffer tank, a pressure reducing valve and a check valve to realize the full system protection function of injecting electrolyte into each pipeline network when the seawater lifting pump group is in operation, and injecting electrolyte into the seawater lifting pump group in reverse when the seawater lifting pump group is shut down. This fully matches the environment of the unprotected seawater lifting pump group of the mobile self-elevating production platform and the characteristics and needs of marine biological control in the seawater system under long-term shutdown conditions.

[0023] At the same time, the electrolytic copper and aluminum device of the present invention is integrated with the filter, a set of devices has bidirectional protection, simple process, compact structure, and no auxiliary injection pipe in the whole process, which reduces the new equipment and pipelines inside the pump tower and the system, with low equipment investment, simple and reliable operation and maintenance, and fully adapts to the low-staff and low-cost operation requirements of marginal oil field development.

[0024] The protection method of the present invention is suitable for three operating conditions, including the operation of the seawater lifting pump group of the single-side pump tower on the port and starboard sides, the simultaneous operation of the seawater lifting pump groups of the double-side pump towers, and the operation of no seawater lifting pump group on both sides of the pump towers. The installation positions of the seawater lifting pump groups in the pump tower are relatively close, and the distance between the suction ports of the two pump seawater lifting pump groups is small. Regardless of whether there is a seawater lifting pump group in operation in a single or double-side pump tower, even the high-speed water flow caused by the operation of a single pump can achieve marine biological protection for all seawater lifting pump groups in the same pump tower.

[0025] It can be seen that the present invention has the advantages of simple process, convenient operation, economical and effective, and safe. It solves the problem of marine organism breeding caused by the lack of protective pipes and long-term shutdown of the seawater lifting pump group of the mobile self-elevating production platform, and realizes the effective prevention and control of marine organisms in the seawater lifting pump without protective pipes and its pipeline network. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The present invention will be described in detail below with reference to the accompanying drawings and in combination with examples, and the advantages and implementation methods of the present invention will become more obvious. The contents shown in the accompanying drawings are only used to explain the present invention and do not constitute any limitation to the present invention in any sense. In the accompanying drawings:

[0027] Figure 1 It is a structural schematic diagram of the present invention.

[0028] Figure 2 It is a schematic structural diagram of the filtering electrolysis device of the present invention.

[0029] In the figure:

[0030] 1. Seawater lifting pump group; 2. Pump tower; 3. Check valve of water lifting pipe in tower; 4. Water outlet hose; 5. First landing manual valve; 6. Filter electrolysis device; 7. Check valve of landing pipeline; 8. Seawater pipe network main; 9. Domestic seawater pump; 10. Seawater pressure cabinet; 11. Pressure reducing valve; 12. Seawater buffer tank; 13. Second landing manual valve; 14. Domestic seawater user; 15. Domestic seawater pipe network; 16. Upper deck pipe network; 601. Cylinder; 602. Infusion port; 603. Filter basket; 604. Cover; 605. Copper electrode; 606. Aluminum electrode. DETAILED DESCRIPTION

[0031] like Figure 1 and Figure 2 As shown, the present invention provides a marine biological prevention pipe network system with an unprotected seawater pump group, comprising a pump tower 2, wherein two seawater lifting pump groups 1 are arranged in the pump tower 2, and the two seawater lifting pump groups 1 are respectively connected to the input end of the water lifting pipe check valve 3 in the tower through the water lifting pipe in the tower, and the output end of the water lifting pipe check valve 3 in the tower is connected to the first landing manual valve 5 through the water outlet hose 4, and the filtering electrolysis device 6, the second landing manual valve 13 and the landing pipeline check valve 7 are sequentially arranged on the upper deck pipe network 16 at the output end of the first landing manual valve 5, and the output end of the landing pipeline check valve 7 is connected to the seawater pipe network main pipe 8 in the cabin, and the seawater pipe network main pipe 8 is respectively connected to the seawater buffer tank 12 and the seawater pressure cabinet 10, and a domestic seawater pump 9 is arranged between the seawater pressure cabinet 10 and the seawater pipe network main pipe 8, and the output end of the seawater pressure cabinet 10 is connected to the domestic seawater user 14 through the domestic seawater pipe network 15.

[0032] The domestic seawater pipe network 15 is connected to the filtering and electrolysis device 6 via a pressure reducing valve 11 .

[0033] There are two pump towers 2, which are respectively installed on the port side and the starboard side of the jack-up production platform.

[0034] Among them, two seawater lifting pump groups 1 are installed close to each other.

[0035] Among them, the seawater lifting pump group 1 is a submerged vertical installation pump group installed in the pump tower 2. The suction port of the seawater lifting pump group 1 is at the connection part with the motor. The seawater lifting pump group 1 has no continuous users and is in a shutdown state most of the time. The flow channels in each stage of the pump are well sealed and have no fluctuations.

[0036] Among them, 2 to 4 discharge holes with a diameter of 8 to 12 mm are arranged on the valve plate of the check valve 3 of the water pipe in the tower. The check valve 3 of the water pipe in the tower prevents most of the seawater from flowing back to the sea surface through the water pipe in the tower of another non-operating seawater lifting pump group 1 when a single seawater lifting pump group 1 is in operation. The discharge holes on the valve plate provide sufficient flow channels for the confluence of the electrolyte. At the same time, only a water volume of no more than 2m³ / h can be discharged under pressure, and the water demand of each pipe network will not be affected.

[0037] The installation position of the filtering and electrolysis device 6 is higher than the pipeline position at the end of the pump tower 2 and is located at the highest point of the upper deck pipeline network 16 .

[0038] Among them, Figure 2 As shown, the filtering electrolysis device 6 includes a cylinder 601, and infusion ports 602 are symmetrically arranged on both sides of the cylinder 601. A filter basket 603 is arranged inside the cylinder 601, and the filter basket 603 is located between the two infusion ports 602. A cover 604 is arranged on the top of the cylinder 601, and a copper electrode 605 and an aluminum electrode 606 are inserted through holes in the cover 604. The filter basket 603 is a detachable structure, and the filter basket 603 is placed on a bracket on the inner wall of the cylinder 601. It can be seen that the filtering electrolysis device 6 is equivalent to using the existing basket filter as an electrolysis device simultaneously, and only the cover needs to be modified, with a small amount of construction, and there is no need to set up a high-investment complete electrolysis device and ancillary injection pipelines. The filtering electrolysis device 6 fully cooperates with the characteristics of the water-lifting pipe check valve 3 in the tower and the check valve 7 in the shore pipeline, forming a two-way protection effect of protecting the pump head of the seawater lifting pump group 1 when the seawater lifting pump group 1 is in operation and the electrolyte enters the upper deck pipeline 16 to achieve pipeline protection; when the seawater lifting pump group 1 is not in operation, the electrolyte flows back to the water-lifting pipe in the tower to achieve water-lifting pipe protection.

[0039] The present invention also provides a method for protecting a marine life-preventing pipe network system having an unprotected seawater pump group, comprising the following steps:

[0040] S1. When the seawater lifting pump group 1 is running:

[0041] S11, the seawater lifting pump group 1 draws seawater, and sends the seawater into the upper deck pipeline 16 through the tower water lifting pipe, the tower water lifting pipe check valve 3 and the water outlet hose 4, and the shore pressure is about 5~7 bar; after passing through the first shore manual valve 5, the filter electrolysis device 6 and the second shore manual valve 13, the electrolytic copper and aluminum liquid electrolyzed by the filter electrolysis device 6 pushes open the shore pipeline check valve 7 and enters the seawater pipeline main 8 in the cabin, and then enters the seawater buffer tank 12 for storage.

[0042] Among them, after the seawater is sent into the upper deck pipeline network 16, it passes through the filtering electrolysis device 6, carrying part of the electrolytic copper and aluminum liquid, and providing preliminary protection for each pipeline network.

[0043] S12, the seawater in the seawater buffer tank 12 is sent to the domestic seawater pump 9 and other users through the seawater pipe network main 8, and the domestic seawater pump 9 pressurizes the seawater and sends it to the domestic seawater pipe network 15 and domestic seawater users through the seawater pressure cabinet 10.

[0044] S2. When the seawater lifting pump group 1 stops running:

[0045] Part of the seawater in the domestic seawater network 15 is decompressed to less than 1 bar by the pressure reducing valve 11 and then enters the filtration electrolysis device 6 to participate in the secondary electrolysis again, and enters the water lifting pipe in the tower through the check valve 3 in the water lifting pipe in the tower, and flows into the stopped seawater lifting pump group 1 through the water lifting pipe in the tower, and after passing through the impellers and guide casings at various levels, it flows out from the suction port of the seawater lifting pump group 1 in the reverse direction.

[0046] Among them, the opening pressure of the shore pipeline check valve 7 is 2~3bar. When the seawater lifting pump group 1 is running, the shore pressure of 5~7bar can open the shore pipeline check valve 7 at any time to introduce seawater into the upper deck pipeline network 16; when the seawater lifting pump group 1 is not running, the low pressure of the secondary electrolyte cannot open the valve, preventing most of the electrolyte from flowing back into the upper deck pipeline network 16, giving priority to ensuring the electrolyte demand of the pump head part of the seawater lifting pump group 1.

[0047] It can be seen that the present invention makes full use of the characteristics of the seawater lifting pump group 1 being in a shutdown state for 90% of the time, being vertically installed, and having good airtightness and no fluctuation in the internal flow channel, and injects the electrolyte in reverse, so that the high-concentration electrolyte directly covers the most critical impellers, bearings and guide shells of the pump body of the seawater lifting pump group 1; at the same time, the suction port of the seawater lifting pump group 1 is located at the connection between the pump and the motor, and the suction port is transformed into an electrolyte outflow port, so that the higher concentration area of ​​the initial diffusion of the electrolyte can cover key positions such as the coupling and the motor shaft extension, ensuring the effective protection of the coupling and the motor shaft extension. Except for the pump casing and the motor casing, all key components of the entire seawater lifting pump group 1 that contact seawater are protected.

[0048] The advantage of selecting the domestic seawater pipeline network 15 as the secondary electrolysis liquid collection point in the present invention is that the pipeline is a necessary user of the mobile self-elevating production platform, has the advantages of small flow, moderate pressure and short distance, and is suitable for the seawater demand of secondary electrolysis.

[0049] The pressure reducing valve 11 serves as a flow limiting device, which can control the seawater pressure within 1 bar and stably deliver it into the filtering electrolysis device 6. The low pressure makes the flow rate of seawater entering the filtering electrolysis device 6 lower, ensuring sufficient time and concentration for electrolysis, while also ensuring the stability and smoothness of the water flow in the water pipe flowing into the tower.

[0050] The embodiments of the present invention are described in detail above, but the contents are only preferred embodiments of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the present invention.

Claims

1. A method for protecting a marine life prevention pipe network system with an unprotected seawater pump group, characterized in that: It comprises a marine life prevention pipe network system, the marine life prevention pipe network system comprises a pump tower, two seawater lifting pump groups are arranged in the pump tower, the two seawater lifting pump groups are respectively connected to the input end of the water lifting pipe check valve in the tower through the water lifting pipe in the tower, the output end of the water lifting pipe check valve in the tower is connected to the first landing manual valve through the water outlet hose, a discharge hole is arranged on the valve plate of the water lifting pipe check valve in the tower, a filtering electrolysis device, a second landing manual valve and a landing pipeline check valve are arranged in sequence on the upper deck pipe network at the output end of the first landing manual valve, the output end of the landing pipeline check valve is connected to the seawater pipe network main pipe in the cabin, the seawater pipe network main pipe is respectively connected to the seawater buffer tank and the seawater pressure cabinet, a domestic seawater pump is arranged between the seawater pressure cabinet and the seawater pipe network main pipe, the output end of the seawater pressure cabinet is connected to the domestic seawater user through the domestic seawater pipe network; the domestic seawater pipe network is connected to the filtering electrolysis device through a pressure reducing valve; The protection method includes the following steps: S1. When the seawater lifting pump group is in operation: S11, the seawater lifting pump group draws seawater, and sends the seawater into the upper deck pipe network through the water lifting pipe in the tower, the check valve of the water lifting pipe in the tower and the water outlet hose; after passing through the first landing manual valve, the filter electrolysis device and the second landing manual valve, the seawater carrying the electrolytic copper and aluminum liquid electrolyzed by the filter electrolysis device pushes open the landing pipeline check valve and enters the seawater pipe network main pipe in the cabin, and then enters the seawater buffer tank for storage; S12, the seawater in the seawater buffer tank is sent to the domestic seawater pump through the seawater pipe network main pipe, and the domestic seawater pump pressurizes the seawater and sends it to the domestic seawater pipe network and domestic seawater users through the seawater pressure cabinet; S2. When the seawater lifting pump group stops running: Part of the seawater in the domestic seawater network is reduced in pressure by the pressure reducing valve and enters the filtration electrolysis device to participate in secondary electrolysis again, and enters the water lifting pipe in the tower through the check valve of the water lifting pipe in the tower, flows into the stopped seawater lifting pump group through the water lifting pipe in the tower, passes through the impellers and guide casings at various stages, and then flows out from the suction port of the seawater lifting pump group in the reverse direction.

2. The method for protecting a marine life-preventing pipe network system with an unprotected seawater pump set according to claim 1, characterized in that: There are two pump towers, which are respectively installed on the port side and the starboard side of the jack-up production platform.

3. The method for protecting a marine life-preventing pipe network system with an unprotected seawater pump set according to claim 1, characterized in that: The seawater lifting pump group is a submerged vertical installation pump group, and the suction port of the seawater lifting pump group is located at the connection part with the motor.

4. The method for protecting a marine life-preventing pipe network system with an unprotected seawater pump set according to claim 1, characterized in that: The valve plate of the check valve of the water-lifting pipe in the tower is provided with 2 to 4 discharge holes with a diameter of 8 to 12 mm.

5. The method for protecting a marine life-preventing pipe network system with an unprotected seawater pump set according to claim 1, characterized in that: The installation position of the filtering and electrolysis device is higher than the pipeline position at the pump tower end and is located at the highest point of the upper deck pipeline network.

6. The method for protecting a marine life-preventing pipe network system with an unprotected seawater pump set according to claim 1, characterized in that: The filtering electrolysis device comprises a cylinder, infusion ports are symmetrically arranged on both sides of the cylinder, a filter basket is arranged inside the cylinder, the filter basket is located between the two infusion ports, a cover is arranged on the top of the cylinder, and copper electrodes and aluminum electrodes are inserted into holes in the cover; the filter basket is a detachable structure, and the filter basket is placed on a bracket on the inner wall of the cylinder.

7. The method for protecting a marine life-preventing pipe network system with an unprotected seawater pump set according to claim 1, characterized in that: The opening pressure of the shore pipeline check valve is 2~3bar. When the seawater lifting pump group is running, the shore pipeline check valve is opened by the shore pressure to introduce seawater into the upper deck pipeline network; when the seawater lifting pump group is not running, the opening pressure of the secondary electrolyte cannot open the shore pipeline check valve.

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