An online oil-water separator suitable for rotating auxiliary equipment of peak shaving units

Abstract

This invention relates to the field of lubrication systems for auxiliary equipment in power plants, and discloses an online oil-water separation device suitable for rotating auxiliary equipment in peak-shaving units. The device includes a circulating oil circuit, a moisture detection module, an oil-water separation module, and a control module. The circulating oil circuit is connected to the main oil tank of the rotating auxiliary equipment to form an oil return channel. The moisture detection module is located in the circulating oil circuit to detect the moisture content of the oil in real time. The oil-water separation module is connected to the circulating oil circuit through a separation control valve. The control module controls the separation control valve based on the moisture detection results: when the moisture content is within the acceptable range, the valve is closed, and the oil returns to the oil tank through the circulating oil circuit, forming a real-time circulation detection loop; when the moisture content exceeds the acceptable range, the valve is opened, and the oil is fed into the oil-water separation module, which consists of a centrifugal separator and a vacuum heating separator connected in series, for dehydration treatment. The qualified oil is then returned to the oil tank. This invention achieves online monitoring and automatic purification of oil, with a rapid response, significantly improving the operational reliability of auxiliary equipment under frequent start-up and shutdown conditions of peak-shaving units.

Description

Technical Field

[0001] This invention relates to the field of lubrication systems for auxiliary equipment in power plants, specifically to an online oil-water separation device suitable for rotating auxiliary equipment in peak-shaving units. Background Technology

[0002] In today's power industry structure, gas turbine units, due to their flexible start-up and shutdown capabilities and rapid response, have become the mainstay for peak shaving in power grids. However, this unpredictable operating mode and frequent start-up and shutdown conditions pose severe reliability challenges to critical rotating auxiliary equipment in gas-fired power plants, such as electric feedwater pumps, circulating water pumps, and their associated motors. These high-power devices are typically equipped with independent lubrication systems for bearing lubrication and cooling. These oil systems generally contain heat exchangers and use water as the cooling medium. During frequent start-ups and shutdowns, each operation causes thermal and mechanical shocks to the equipment, which can easily lead to aging and failure of the oil system seals in the pump bearings, or gaps in the sealing surfaces due to vibration. Simultaneously, under long-term alternating hot and cold conditions, the tube bundles or expansion joints of the heat exchanger are more prone to leakage. These factors combined make cooling water entering the oil system a frequent and extremely dangerous safety hazard in gas-fired power plants.

[0003] When water enters the lubricating oil system, it rapidly causes oil emulsification and deterioration, disrupting oil film formation and significantly reducing lubrication performance. In severe cases, it can even lead to major accidents such as bearing failure and equipment damage. Currently, the industry's approach to dealing with water ingress into oil systems is mostly reactive, relying on periodic manual sampling and testing to detect problems. Once the oil quality is substandard, shutdown is often required, or offline oil filters are used for prolonged circulation filtration. This approach is not only slow to respond, but also lacks sufficient processing time in peak-shaving power plants where units frequently start and stop and may receive grid connection commands at any time. Furthermore, the oil system remains in a high-risk operating state during offline processing. Therefore, there is an urgent need for a device that can adapt to the variable operating conditions of peak-shaving units, enabling real-time online monitoring and automatic separation and purification of oil moisture. This device should proactively intervene when oil quality first shows signs of deterioration, nipping potential problems in the bud and fundamentally improving the operational safety of critical auxiliary equipment in gas-fired power plants. Summary of the Invention

[0004] (a) Technical problems to be solved To address the shortcomings of existing technologies, this invention provides an online oil-water separation device suitable for rotating auxiliary equipment of peak-shaving units. This device solves the problems of lagging water treatment in the oil system and inability to adapt to the changing operating conditions of peak-shaving units, which leads to prolonged high-risk operation of the equipment during periods of oil deterioration.

[0005] (II) Technical Solution To address the shortcomings of existing technologies, such as delayed water treatment in oil systems and inability to adapt to varying operating conditions of peak-shaving units, this invention provides the following technical solution: An online oil-water separation device suitable for rotating auxiliary equipment of peak shaving units, comprising: A circulating oil circuit is used to connect to the main oil tank of the rotating auxiliary machine to form an oil passage for taking oil from the main oil tank and returning it. A moisture detection module is installed in the circulating oil circuit to detect the moisture content in the oil in real time. The oil-water separation module is connected to the circulating oil circuit via a separation control valve; and The control module is signal-connected to the moisture detection module and the separation control valve; The control module is configured as follows: when the moisture content detected by the moisture detection module does not exceed the preset value, the separation control valve is closed, allowing the oil to flow through the circulating oil circuit back to the main oil tank, forming a real-time circulating detection loop; when the moisture content detected by the moisture detection module exceeds the preset value, the separation control valve is opened, cutting the oil into the oil-water separation module for dehydration treatment, and the treated oil is then returned to the main oil tank.

[0006] The oil inlet of the circulating oil circuit is located at the lowest point of the main oil tank.

[0007] The oil-water separation module includes a centrifugal separator and a vacuum heating separator connected in series.

[0008] The circulating oil circuit is equipped with an oil pump to provide power for oil circulation.

[0009] The oil pump inlet is connected to a buffer oil tank in the circulating oil line. The outlet pipe of the buffer oil tank is equipped with a replenishment control valve, which is used to quickly replenish oil through the buffer oil tank when the total oil level of the rotating auxiliary machine drops.

[0010] The preset normal value for the moisture detection module is less than 0.1%.

[0011] The return port of the circulating oil circuit is equipped with a check valve.

[0012] (III) Beneficial Effects Compared with the prior art, the present invention provides an online oil-water separation device suitable for the rotating auxiliary equipment of peak shaving units, which has the following beneficial effects: This online oil-water separation device, applicable to the auxiliary equipment of peak-shaving units, constructs a real-time circulation detection loop through an oil circuit circulation module. A moisture detection module monitors oil quality online, and a control module automatically controls the opening and closing of the separation control valve based on the detection results. When the moisture content exceeds the standard, the oil automatically switches to the oil-water separation module, composed of a centrifugal separator and a vacuum heating separator, for dehydration. Qualified oil returns to the oil tank via a check valve. The oil inlet is located at the lowest point of the oil tank to ensure priority extraction of water-containing oil; a buffer tank allows for rapid replenishment when the oil level drops. This device achieves online monitoring and automatic purification of oil quality, responds quickly, eliminates potential problems, and significantly improves the operational reliability of auxiliary equipment under frequent start-up and shutdown conditions of peak-shaving units. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is a block diagram illustrating the control principle of the present invention.

[0014] In the diagram: 1. Circulating oil circuit; 2. Main oil tank; 3. Moisture detection module; 4. Oil-water separation module; 401. Separation control valve; 402. Centrifugal separator; 403. Vacuum heating separator; 5. Control module; 6. Oil pump; 7. Buffer oil tank; 8. Oil replenishment control valve; 9. Check valve; 10. Recirculation valve; 11. Audible and visual alarm; 12. Main inlet valve; 13. Separation device inlet valve; 14. Separation device outlet valve. Detailed Implementation

[0015] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0016] Please see Figure 1-2 An online oil-water separation device for rotating auxiliary equipment of peak-shaving units is designed to address the problems of frequent start-up and shutdown of rotating auxiliary equipment, easy water ingress into the oil system, and outdated existing treatment methods caused by gas-fired power plants undertaking grid peak-shaving tasks. The system includes: a circulating oil circuit 1, connected to the main oil tank 2 of the auxiliary machine, forming an oil passage for taking oil from the main oil tank 2 and returning it; a moisture detection module 3, installed in the circulating oil circuit 1, for real-time detection of the moisture content in the oil; an oil-water separation module 4, connected to the circulating oil circuit 1 via a separation control valve 401; and a control module 5, signal-connected to the moisture detection module 3 and the separation control valve 401. The control module 5 is configured to: when the moisture content detected by the moisture detection module 3 does not exceed a preset value, control the separation control valve 401 to close, allowing the oil to flow through the circulating oil circuit 1 back to the main oil tank 2, forming a real-time circulating detection loop; when the moisture content detected by the moisture detection module 3 exceeds the preset value, control the separation control valve 401 to open, cutting the oil into the oil-water separation module 4 for dehydration treatment, and then returning the treated oil to the main oil tank 2.

[0017] It should be noted that the moisture detection module 3 is an online oil moisture monitor, which uses a capacitive or impedance sensor principle to accurately measure the water content by utilizing the difference in dielectric constant between water and oil. When the oil flows through the sensor, the probe detects the change in capacitance of the oil-water mixture in real time and converts it into a standard electrical signal, which is then output to the control module 5.

[0018] As a specific implementation method, the OMM300 series oil moisture sensor or the MAZ-Cm100 series online oil ultra-trace moisture detector can be selected, which has an IP66 protection rating and a wide operating temperature range (-40℃ to +80℃), and can adapt to the harsh working conditions of continuous operation of power plant auxiliary equipment.

[0019] In this embodiment, a main inlet valve 12 is provided at the oil inlet of the circulating oil circuit 1, which is used to disconnect the connection with the main oil tank 2 when the device is under maintenance or shut down for a long period of time to prevent oil leakage.

[0020] In this embodiment, the oil inlet of the circulating oil circuit 1 is located at the lowest point of the main oil tank 2.

[0021] It should be noted that, since water is denser than oil, the water entering the main oil tank 2 will settle at the bottom of the tank under gravity. By placing the oil sampling port at the lowest point, the oil with the highest water content can be extracted first and sent to the detection and separation process. This avoids the ineffective circulation of the relatively qualified oil in the upper layer, and significantly improves the sensitivity of water detection and the efficiency of separation.

[0022] In this embodiment, the oil-water separation module 4 includes a centrifugal separator 402 and a vacuum heating separator 403 connected in series.

[0023] It should be noted that the oil first enters the centrifugal separator 402, where the centrifugal force generated by high-speed rotation initially separates the large, free water droplets. Subsequently, the oil enters the vacuum heating separator 403, where, under negative pressure and moderate heating conditions, the emulsified small water droplets vaporize and escape from the oil. This two-stage, series-connected physical separation method effectively addresses different forms of moisture, ensuring that the treated oil meets acceptable standards, and achieving deep purification even with significant water ingress.

[0024] In one specific implementation, the centrifugal separator 402 can be a Kaeser KC series centrifugal separator, such as model F9KC, F26KC, or F46KC, with a separation efficiency of 97%-99% and a working pressure of 2-16 bar, which can meet the operating requirements of the lubrication system of the auxiliary rotating machinery in power plants. The vacuum heating separator 403 can be a vacuum separation unit in the ZJCQ series turbine oil online purification device, such as the ZJCQ-3 or ZJC-50 vacuum oil purifier, with a working vacuum degree of up to 0.098 MPa, which can effectively remove emulsified water and gas from the oil.

[0025] In this embodiment, the oil-water separation module 4 is provided with a separation device inlet gate 13 at the inlet end and a separation device outlet gate 14 at the outlet end, which is used to isolate the oil-water separation module 4 when it needs maintenance or malfunctions, so as to facilitate online maintenance without affecting the normal operation of the circulating oil circuit 1.

[0026] In this embodiment, an oil pump 6 is provided in the circulating oil circuit 1 to provide power for oil circulation.

[0027] It should be noted that the oil pump 6 operates continuously to ensure that the circulating oil circuit 1 always maintains oil flow, so that the moisture detection module 3 can obtain representative oil samples in real time and avoid detection delays caused by stagnant oil.

[0028] In one specific implementation, the oil pump 6 can be a 2CY series gear oil pump, such as the 2CY-1.08 / 2.5 type or the 2CY-3 / 2.5 type, which is suitable for conveying lubricating oil, with a discharge pressure of up to 2.5MPa and a flow rate range of 1.08-3m³ / h, and can provide stable and reliable power output for the circulating oil circuit 1 of this device.

[0029] In this embodiment, a buffer oil tank 7 is also connected to the circulating oil circuit 1 before the inlet of the oil pump 6. An oil replenishment control valve 8 is provided on the outlet pipe of the buffer oil tank 7, which is used to quickly replenish oil through the buffer oil tank 7 when the oil level of the main oil tank 2 of the rotating auxiliary machine drops.

[0030] It should be noted that the control module 5 is connected to the oil replenishment control valve 8. When the oil-water separation module 4 runs for a long time or the oil level in the main oil tank 2 drops due to equipment leakage or other reasons, the control module 5 can automatically open the oil replenishment control valve 8 to replenish the qualified oil stored in the buffer oil tank 7 into the circulating oil circuit 1 and into the main oil tank 2, so as to maintain the oil level in the main oil tank 2 within a safe range and avoid the oil pump 6 from sucking in air or the bearing from insufficient oil supply due to the oil level being too low.

[0031] It should be further explained that regarding the detection of the oil level in the main oil tank 2, in this embodiment, an oil level sensor is installed on the main oil tank 2 to monitor the changes in the oil level in the main oil tank 2 in real time. The oil level sensor is connected to the control module 5 and can be a magnetostrictive level gauge or a hydrostatic level gauge, such as the UHZ-50 series magnetic float level gauge or the WIDEPLACE-WP series submersible level transmitter, which outputs a 4-20mA standard analog signal to the control module 5. The control module 5 has a preset low oil level alarm threshold. When the received oil level signal is lower than this set value, it is determined that the oil level in the main oil tank 2 has dropped to a dangerous range, and then the oil replenishment control valve 8 is automatically opened to replenish oil.

[0032] In this embodiment, the preset normal value of the moisture detection module 3 is less than 0.1%.

[0033] It should be noted that this threshold is set according to the operating standards of lubricating oil for auxiliary equipment in power plants. When the moisture content is below 0.1%, it is considered qualified and only circulation testing is performed; when it reaches or exceeds 0.1%, it is considered abnormal and the separation process is immediately started to ensure that the oil quality is always under control.

[0034] In this embodiment, a check valve 9 is provided at the return port of the circulating oil circuit 1.

[0035] It should be noted that the non-return valve 9 is used to prevent the oil in the main oil tank 2 from flowing back into the circulation pipeline when the oil pump 6 stops or the pressure fluctuates, so as to avoid oil circuit disorder and air mixing and ensure the stability of system operation.

[0036] In this embodiment, a recirculation gate 10 is also provided at the return port of the circulating oil circuit 1.

[0037] The recirculation gate 10 is located before the check valve 9. When the separation control valve 401 is closed, the oil returns to the main oil tank 2 through the recirculation gate 10 and the check valve 9, forming a circulation detection loop.

[0038] In a preferred embodiment, the control module 5 is also connected to an audible and visual alarm 11. When the moisture detection module 3 detects that the moisture content exceeds a preset value and does not improve after a certain period of time (e.g., 30 seconds), the control module 5 activates the audible and visual alarm to prompt the operators to pay attention to the oil system status and perform necessary checks and confirmations.

[0039] In a preferred embodiment, the separation control valve 401 is an electrically operated three-way valve. Its first port is connected to the outlet of the moisture detection module 3, its second port is connected to the recirculation pipeline, and its third port is connected to the inlet of the oil-water separation module 4. When the moisture content is within acceptable limits, the first and second ports are connected, and the oil returns to the main oil tank 2 via the recirculation pipeline. When the moisture content exceeds the limit, the first and third ports are connected, and the oil flows into the oil-water separation module 4. The single-valve structure simplifies pipeline connections, reduces leakage points and the number of control components, and improves system reliability.

[0040] In summary, this online oil-water separation device, applicable to the auxiliary equipment of peak-shaving units, constructs a real-time circulation detection loop through an oil circuit circulation module. The moisture detection module 3 monitors oil quality online, and the control module 5 automatically controls the opening and closing of the separation control valve 401 based on the detection results. When the moisture content exceeds the standard, the oil automatically enters the oil-water separation module 4, composed of a centrifugal separator 402 and a vacuum heating separator 403, for dehydration. Qualified oil returns to the oil tank via the check valve 9. The oil inlet is located at the lowest point of the oil tank to ensure priority extraction of water-containing oil; the buffer tank 7 can quickly replenish oil when the oil level drops. This device achieves online monitoring and automatic purification of oil quality, responds rapidly, eliminates potential accidents, and significantly improves the operational reliability of auxiliary equipment under frequent start-up and shutdown conditions of peak-shaving units.

[0041] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. An online oil-water separation device suitable for the rotating auxiliary equipment of a peak-shaving unit, characterized in that, include: The circulating oil circuit (1) is used to connect to the main oil tank (2) of the rotating auxiliary machine to form an oil passage for taking oil from the main oil tank (2) and returning it; A moisture detection module (3) is installed in the circulating oil circuit (1) to detect the moisture content in the oil in real time. The oil-water separation module (4) is connected to the circulating oil circuit (1) via the separation control valve (401); as well as The control module (5) is signal-connected to the moisture detection module (3) and the separation control valve (401); The control module (5) is configured to: when the moisture content detected by the moisture detection module (3) does not exceed the preset value, control the separation control valve (401) to close, so that the oil flows through the circulation oil circuit (1) back to the main oil tank (2) to form a real-time circulation detection loop; when the moisture content detected by the moisture detection module (3) exceeds the preset value, control the separation control valve (401) to open, so that the oil is cut into the oil-water separation module (4) for dehydration treatment, and the treated oil is returned to the main oil tank (2) through the circulation oil circuit (1).

2. The online oil-water separation device for rotating auxiliary equipment of peak-shaving units according to claim 1, characterized in that, The oil inlet of the circulating oil circuit (1) is located at the lowest point of the main oil tank (2).

3. The online oil-water separation device for rotating auxiliary equipment of peak-shaving units according to claim 1, characterized in that, The oil-water separation module (4) includes a centrifugal separator (402) and a vacuum heating separator (403) connected in series.

4. The online oil-water separation device for rotating auxiliary equipment of peak-shaving units according to claim 1, characterized in that, The circulating oil circuit (1) is equipped with an oil pump (6) to provide power for oil circulation.

5. The online oil-water separation device for rotating auxiliary equipment of peak-shaving units according to claim 4, characterized in that, A buffer oil tank (7) is also connected to the circulating oil circuit (1) before the inlet of the oil pump (6). An oil replenishment control valve (8) is provided on the outlet pipe of the buffer oil tank (7) for quickly replenishing oil through the buffer oil tank (7) when the oil level of the main oil tank (2) of the rotating auxiliary machine drops.

6. The online oil-water separation device for rotating auxiliary equipment of peak-shaving units according to claim 1, characterized in that, The preset normal value for the moisture detection module (3) is less than 0.1%.

7. The online oil-water separation device for rotating auxiliary equipment of peak-shaving units according to claim 1, characterized in that, A check valve (9) is provided at the return port of the circulating oil circuit (1).

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