Method and apparatus for regenerating insulating oil

Abstract

To provide a method and a device for automatically / semi-automatically regenerating / wasting insulating oil used for an oil-filled electric apparatus.SOLUTION: The deterioration state of the insulating oil 3 is grasped from the measurement result of the measuring instrument 12, and when the insulation oil 3 is in a deterioration state in which regeneration is possible, the insulation oil 3 is regenerated through deaeration treatment and filtration treatment. When the regeneration is impossible, it is discarded without regeneration. The oil feed route of the insulating oil 3 for performing the regeneration treatment and the disposal treatment is automatically / semi-automatically switched and controlled in linkage with the measurement result of the measuring instrument 12.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a method and an apparatus for reclaiming or disposing of insulating oil used in oil-filled electrical equipment. [Background technology]

[0002] Conventionally, when overhauling oil-filled electrical equipment such as oil-filled transformers, a method has been known in which the insulating oil is first removed from the electrical equipment, the electrical equipment is inspected and maintained, and then the insulating oil removed from the electrical equipment is purified and returned to the electrical equipment (see Patent Document 1 below). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2002-15922 [Patent Document 2] Patent Publication No. 2021-121001 Summary of the Invention [Problem to be solved by the invention]

[0004] The device described in Patent Document 1 purifies insulating oil by circulating it between an oil collection tank and a purification tower. Therefore, metal powder and sludge, which tend to settle, accumulate at the bottom of the oil collection tank and cannot be completely removed. Furthermore, because the connecting pipes are shared for oil draining and oil return, there is a possibility that metal powder and sludge may adhere to the oil during oil draining. Therefore, when the insulating oil in the purified oil collection tank is returned to the overhauled electrical equipment, there is a possibility that sludge adhering to the connecting pipes or sludge accumulated at the bottom of the oil collection tank may be mixed in.

[0005] To solve this problem, the invention described in Patent Document 2 does not share pipes for oil draining and oil returning, and instead removes moisture and decomposition gases in a degassing process, and then filters out solids such as carbon and sludge using an oil feed pump before injecting the insulating oil into electrical equipment, thereby preventing the intrusion of metal powder and solids such as carbon and sludge.

[0006] However, the method described in Patent Document 1 only discloses a technique for reusing insulating oil from electrical equipment, and does not disclose a technique for disposing of insulating oil that has deteriorated to the point where it cannot be reused. Also, in the process of decompressing the oil treatment tank with a vacuum pump and degassing the insulating oil in the oil treatment tank, it is necessary to prevent the insulating oil from flowing into the vacuum pump, but a specific method for this is not disclosed.

[0007] Therefore, the present invention discloses a technology not disclosed in the above Patent Document 2, and provides an insulating oil recycling method and recycling device that have been improved to enable more effective and efficient recycling of insulating oil in electrical equipment. [Means for solving the problem]

[0008] The invention described in claim 1 is a method for regenerating insulating oil, characterized by measuring the deterioration state of insulating oil in oil-filled electrical equipment, selecting a method for regenerating the insulating oil or selecting disposal of the insulating oil depending on the measurement results, and switching the oil transport route for the insulating oil depending on the selection results.

[0009] The invention described in claim 2 is the insulating oil regeneration method described in claim 1, characterized in that the regeneration method makes it possible to select whether to add degassing in the tank to which the insulating oil is transferred and filtration of the insulating oil through a filter to the degassing.

[0010] The invention described in claim 3 is the insulating oil regeneration method described in claim 1, characterized in that the degassing is performed by vacuuming the tank from the upper position using a vacuum pump, or by vacuuming the tank using a vacuum pump through an oil inflow prevention means installed on the inner surface of the tank, thereby preventing the insulating oil in the tank from flowing into the vacuum pump.

[0011] The invention of claim 4 is a method for detecting the deterioration state of insulating oil by measuring the color, conductivity, dielectric constant, dynamic viscosity, density, turbidity, etc. of the insulating oil. 3. The insulating oil regeneration method according to claim 1, wherein the insulating oil content is measured based on one or more of the physical properties of the insulating oil, such as viscosity, transmittance, volume resistivity, dielectric loss tangent, surface tension, acid value, breakdown voltage, moisture content, and flash point.

[0012] The invention described in claim 5 is a method for regenerating insulating oil described in claim 2, characterized in that the filter that filters the insulating oil is equipped with an adsorbent, and the degraded products of the insulating oil are adsorbed by the adsorbent, and the insulating oil that passes through the filter is heated to a temperature at which the adsorption effect of the adsorbent is enhanced.

[0013] The invention described in claim 6 is a method for regenerating insulating oil described in claim 5, characterized in that a plurality of filters are installed, each filter having a different adsorbent, and it is possible to select which of the filters the insulating oil will pass through.

[0014] The invention described in claim 7 is a method for regenerating insulating oil according to claim 5, characterized in that it is equipped with a pressure gauge that measures the pressure inside the pipe through which the insulating oil is transported, and the clogging of the filter is determined from the measurement results of the pressure gauge, and the time to replace the filter is determined.

[0015] The invention described in claim 8 is an insulating oil regeneration treatment device characterized by comprising a control unit that measures the deterioration state of insulating oil in oil-filled electrical equipment, selects a method of regenerating the insulating oil or selects disposal of the insulating oil depending on the measurement result, and switches the oil transport route of the insulating oil depending on the selection result.

[0016] The invention described in claim 9 is an insulating oil regeneration treatment device described in claim 8, characterized in that the control unit can select, as a regeneration method, whether to degas the insulating oil in the tank to which it is transferred or to add filtration of the insulating oil through a filter to the degassing.

[0017] The invention described in claim 10 is an insulating oil recycling treatment device described in claim 8, characterized in that the degassing is performed by using a vacuum pump to draw a vacuum from the upper position of the tank, or by using a vacuum pump to draw a vacuum through an oil inflow prevention means installed on the inside surface of the tank, thereby preventing the insulating oil in the tank from flowing into the vacuum pump.

[0018] The invention described in claim 11 is an insulating oil recycling treatment device described in claim 10, characterized in that the oil inflow prevention means consists of a bottomed semi-cylindrical portion having an opening at the top and an umbrella portion located above the opening. [Effects of the Invention]

[0019] According to the inventions of claims 1 and 8, it is possible to switch between regenerated and waste oil depending on the deterioration state of the insulating oil.

[0020] According to the inventions of claims 2 and 9, it is possible to select a regeneration method according to the deterioration state of the insulating oil.

[0021] According to the inventions set forth in claims 3, 10 and 11, it is possible to reliably prevent insulating oil from flowing into the vacuum pump, thereby preventing breakdowns and malfunctions.

[0022] According to the invention of claim 4, by measuring the color, conductivity, dielectric constant and other physical properties of the insulating oil, it is possible to reliably grasp the deterioration state of the insulating oil.

[0023] According to the invention of claim 5, the degraded products contained in the insulating oil can be reliably removed by the adsorbent in the filter. In addition, by heating the insulating oil passing through the filter to a predetermined temperature, the efficiency of removing the degraded products by the adsorbent can be increased.

[0024] According to the invention described in claim 6, by using different adsorbents in multiple filters, it is possible to appropriately select the filter through which the insulating oil to be regenerated passes, thereby filtering the insulating oil using a filter that suits the current state of the insulating oil.

[0025] According to the invention of claim 7, by measuring the pressure inside the pipe with a pressure gauge, it is possible to grasp the clogging of the filter from the measurement results and identify the time to replace the filter. [Brief explanation of the drawings]

[0026] [Figure 1] 1 is a block diagram showing an embodiment of an insulating oil recycling treatment device of the present invention. [Figure 2] FIG. 2 is a block diagram showing another embodiment of the insulating oil recycling treatment device of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0027] An embodiment of the present invention will be described with reference to Fig. 1. Fig. 1 is a configuration diagram of an insulating oil reclamation treatment device A according to the present invention. In Fig. 1, 1 is a tank for an oil-filled electrical device such as a transformer, and 2 is the main body of the electrical device installed in tank 1. The main body of the electrical device 2 is made up of a coil 2a, an iron core 2b, etc., and is immersed in insulating oil 3 filled in tank 1.

[0028] Reference numeral 4 denotes a filtering device connected to the inside of the tank 1 by oil supply pipes 5a and 5b, and reference numeral 6 denotes a filter containing an adsorbent (not shown). The adsorbent may be a known adsorbent (such as clay or activated alumina).

[0029] Reference numeral 7 denotes a heater for heating the insulating oil flowing through pipe 9 in the filtration device 4, and 8 denotes a pressure gauge for measuring the dynamic pressure of the insulating oil flowing through pipe 9. Reference numeral 10 denotes a pump for causing the insulating oil to flow through pipe 9, and 11 denotes a valve attached to pipe 9 between filter 6 and heater 7.

[0030] Reference numeral 12 denotes a measuring instrument consisting of a conductivity meter or a dielectric constant meter, etc., installed on the oil supply pipe 5c which is connected to the oil supply pipes 5a and 5b, 13a denotes a valve installed on the oil supply pipe 5a, and 13b denotes a valve installed on the oil supply pipe 5b.

[0031] Reference numeral 14a denotes an oil supply pipe for supplying insulating oil 3 in tank 1 of oil-filled electrical equipment, and 15 denotes a new oil tank for storing unused insulating oil (new oil) 3a. Reference numeral 16 denotes an oil supply pipe for supplying new oil 3a in new oil tank 15, and 17 denotes a valve installed on oil supply pipe 16.

[0032] Reference numeral 18 denotes a valve for allowing the insulating oil 3 flowing through the oil supply pipe 14a or new oil flowing through the oil supply pipe 16 to flow into the oil supply pipe 14b, and 19 denotes an oil treatment tank for storing the insulating oil 3b that has been degassed. Reference numeral 20 denotes a nozzle attached to the tip of the oil supply pipe 14b that passes through the oil treatment tank 19 from the top, and 21 denotes a vacuum pump for reducing the pressure inside the oil treatment tank 19.

[0033] Reference numeral 22 denotes a valve that is opened when the vacuum pump 21 reduces the pressure inside the oil treatment tank 19, and 23 denotes a pressure gauge for measuring the pressure inside the oil treatment tank 19. The pressure gauge 23 is used to manage the pressure inside the oil treatment tank 19 that is reduced in pressure by the vacuum pump 21.

[0034] Reference numeral 24 denotes an oil inflow prevention unit installed in oil treatment tank 19, which prevents insulating oil 3b from flowing into vacuum pump 21 when vacuum pump 21 reduces the pressure inside oil treatment tank 19. The oil inflow prevention unit 24 may be structured, for example, with a bottomed semi-cylindrical portion 24a having an opening at the top and an umbrella portion 24b located above the opening, and is installed by fixing one side of bottomed semi-cylindrical portion 24a and umbrella portion 24b to the inner circumferential surface of oil treatment tank 19 by welding or the like. Reference numeral 25 denotes a valve for returning the pressure inside oil treatment tank 19 to atmospheric pressure.

[0035] Reference numeral 26 denotes a discharge pipe connected to the lower drain of the oil treatment tank 19, and 27 denotes a valve installed on the discharge pipe. Reference numeral 28 denotes a waste oil pipe that is connected to the oil supply pipe 5d or the discharge pipe 26 by switching operation of a valve 29, and by switching operation of the valve 29, the insulating oil 3b flowing through the discharge pipe 26 is made to flow into the oil supply pipe 5d or into the waste oil pipe 28. Reference numeral 30 denotes a waste oil tank that receives the insulating oil 3b discharged via the waste oil pipe 28.

[0036] Next, the operation of the insulating oil regeneration treatment device A configured as described above will be explained. This operation is controlled by a control unit (not shown). When the insulating oil in an oil-filled electrical device is to be regenerated or replaced with new oil, oil feed pipe 14a is inserted into tank 1, and valve 18 is switched to connect the inside of oil treatment tank 19 to the inside of tank 1 via oil feed pipes 14a and 14b.

[0037] In this state, valve 22 is opened and vacuum pump 21 is driven to suck up insulating oil 3 in tank 1 via oil feed pipes 14a and 14b. The sucked-up insulating oil 3 is sprayed from nozzle 20 into oil treatment tank 19 in the form of a shower or mist. By spraying insulating oil 3 in the form of a shower or mist, moisture and decomposition gases contained in insulating oil 3 are removed. Umbrella portion 24b of oil inflow prevention portion 20 prevents insulating oil 3 sprayed from nozzle 20 from entering bottomed semi-cylindrical portion 24a.

[0038] The insulating oil from which moisture and decomposition gases have been removed is stored in oil treatment tank 19. Next, valve 18 is switched to continue driving vacuum pump 21 for a predetermined time, thereby reducing the pressure inside oil treatment tank 19 to a predetermined level. The predetermined pressure is managed by pressure gauge 23.

[0039] When the pressure inside the oil treatment tank 19 is reduced, the insulating oil 3b inside the oil treatment tank 19 can be reliably prevented from flowing into the vacuum pump 21 by the oil inflow prevention unit 24. By reducing the pressure inside the oil treatment tank 19 to a predetermined level, the moisture and decomposition gases contained in the insulating oil 3b inside the oil treatment tank 19 can be further removed.

[0040] Next, valve 25 is opened and the pressure inside oil treatment tank 19 is returned to atmospheric pressure. Then, valve 27 is opened, and with either valve 13a or valve 13b open, valve 29 is switched to connect discharge pipe 26 and oil supply pipe 5d, and pump 10 of filtration device 4 is driven, thereby allowing insulating oil 3b to flow from discharge pipe 26 through oil supply pipe 5d into pipe 9 of filtration device 4.

[0041] In the filtering device 4, the dynamic pressure of the insulating oil 3b flowing through the pipe 9 is measured by a pressure gauge 8, and the insulating oil 3b is heated to a predetermined temperature (for example, 40°C) by a heater 7. The temperature of the insulating oil 3b is measured by a measuring device such as a temperature sensor (not shown). The heated insulating oil 3b flows into the oil supply pipe 5b or into the filter 4 depending on the switching state of the valve 11.

[0042] When the insulating oil 3b flows into the oil supply pipe 5b, the degree of deterioration of the insulating oil 3b is measured by a measuring instrument 12 on the oil supply pipe 5c, and then the insulating oil 3b is supplied into the tank 1. In this case, the insulating oil 3 in the tank 1 is degassed in the oil treatment tank 19 to remove moisture and decomposition gases contained in the insulating oil 3, and the insulating oil 3 is returned to the tank 1.

[0043] When the oil flows into the filter 6, solid matter such as carbon and sludge is removed by the adsorbent in the filter 6. The insulating oil 3b that has passed through the filter 6 has its degree of deterioration measured by a measuring instrument 12 on the oil supply pipe 5c, and is then fed into the tank 1. In this case, the insulating oil 3 in the tank 1 is degassed in the oil treatment tank 19, and then has fixed matters such as carbon and sludge removed by the filtration device 4 before being returned to the tank 1.

[0044] When the insulating oil 3b is passed through the filter 6, it is heated to a temperature (40°C) at which the adsorbent improves its adsorption efficiency, and carbon, sludge, etc. can be efficiently removed. Therefore, when the insulating oil 3b is not passed through the filter 6, there is no need to heat the insulating oil 3b with the heater 7.

[0045] In this way, the deterioration state of the insulating oil 3 in the tank 1 is improved by passing it through the oil treatment tank 19 and the filtration device 4, and it can be returned as recycled oil to the tank 1. By repeating this recycling process, the measurement value by the measuring instrument 12 on the oil supply pipe 5c indicates that the degree of deterioration has improved.

[0046] As the above-mentioned filtration is repeated, the filter 6 of the filtration device 4 becomes clogged with the adhesion of solid matter such as carbon and sludge. When this happens, the dynamic pressure of the insulating oil 3b measured by the pressure gauge 8 on the pipe 9 rises, and the time to replace the filter 6 can be determined from the reading of the pressure gauge 8. It is also possible to configure the system to be easy for the manager to manage, for example, by linking the pressure gauge 8 to light up a lamp to indicate when it is time to replace the filter 6.

[0047] Furthermore, the insulating oil recycling treatment device A can also mix new oil 3a and return it to the tank 1 during the process of regenerating the insulating oil 3 in the tank 1. In this case, around the time of oil transfer from the tank 1 to the oil treatment tank 19, valve 18 is switched to connect the oil supply pipe 16 to the oil transfer pipe 14b, valves 17 and 22 are opened, and valve 25 is closed. By operating the vacuum pump 21, the new oil 3a is transferred from the oil supply pipe 16 through the oil transfer pipe 14b and the nozzle 20 into the oil treatment tank 19. The umbrella portion 24b of the oil inflow prevention unit 20 prevents the new oil 3a transferred from the nozzle 20 into the bottomed semi-cylindrical portion 20a. In the oil treatment tank 19, the insulating oil 3 transferred from the tank 1 and the new oil 3a transferred from the new oil tank 15 are mixed.

[0048] The process of returning the mixed insulating oil 3b to the tank 1 through the filtration device 4 is the same as that described above. After the insulating oil 3 and new oil 3a are mixed, the state of deterioration of the insulating oil 3b is dramatically improved, and it can be returned to the tank 1 as recycled oil, and the measurement value of the measuring instrument 12 also improves.

[0049] If the insulating oil 3 in the tank 1 cannot be expected to improve even by the above-mentioned regeneration treatment, the insulating oil 3 in the tank 1 can be discarded and only new oil 3a can be poured into the tank 1. When pouring only new oil 3a into the tank 1, first, the valve 18 is switched to connect the inside of the tank 1 to the inside of the oil treatment tank 19 via the oil feed pipes 14a and 14b.

[0050] In this state, the valve 22 is opened and the vacuum pump 21 is driven to suck up the insulating oil 3 in the tank 1 through the oil transfer pipes 14 a and 14 b and transfer it into the oil treatment tank 19 .

[0051] Once the transfer of the insulating oil 3 is complete, valves 25 and 27 are opened and valve 29 is switched to connect the discharge pipe 26 and the waste oil pipe 28, thereby discharging the insulating oil 3 from the discharge pipe 26 through the waste oil pipe 28 to the waste oil tank 30.

[0052] Next, valves 25 and 27 are closed, valve 17 is opened, and valve 18 is used to connect oil supply pipe 16 and oil transfer pipe 14b. With this in place, pump 21 is driven to store new oil 3a in new oil tank 15 in oil treatment tank 19. Once new oil 3a has been stored in oil treatment tank 19, valve 29 is used to connect discharge pipe 26 and oil supply pipe 5d.

[0053] Next, valve 27 is opened, and with either valve 13a or valve 13b open, pump 10 of filtration device 4 is driven, thereby injecting new oil 3a from oil treatment tank 19 into tank 1 through oil treatment tank 19, discharge pipe 26, oil supply pipe 5d, pipe 9 of filtration device 4, and oil supply pipes 5a, 5b, and 5c.

[0054] The new oil 3a may be returned to the tank 1 through the filter 4 after being heated by the heater 7, or may be returned to the tank 1 through the oil supply pipe 5b without being heated by the heater 7.

[0055] The insulating oil regeneration treatment device A can perform the above operations automatically or semi-automatically. For example, if the measurement by the measuring device 12 shows that the insulating oil is not very deteriorated, the device controls the various valves and pumps to skip filtration by the filter 6 and only perform degassing treatment in the oil treatment tank 19.

[0056] If the measuring instrument 12 indicates that the degree of deterioration of the insulating oil is advanced, the various valves and pumps are controlled to perform both filtration by the filter 6 and degassing treatment in the oil treatment tank 19. Alternatively, the various valves and pumps are controlled to mix the insulating oil 3 in the tank 1 with the insulating oil in the new oil tank 15 and return the mixture to the tank 1.

[0057] If the insulating oil is severely deteriorated and cannot be recycled, the various valves and pumps are controlled so that the insulating oil 3 is discharged to a waste oil tank 29 and only new oil 3a is poured into the tank 1. Of course, it is also possible to manually operate all or part of these various valves and pumps.

[0058] 1 has been described as a case where oil inflow prevention unit 24 is installed in oil treatment tank 19, but the vacuum pump 21 and valve 22 may be attached at the positions shown by dotted lines in Fig. 1, and insulating oil 3b may be prevented from flowing into vacuum pump 21 by drawing a vacuum from the top of oil treatment tank 19. With such a configuration, oil inflow prevention unit 24 is not necessary, making it possible to reduce the cost of the device.

[0059] Next, another embodiment of the present invention will be described. Figure 2 is a configuration diagram of an insulating oil recycling treatment device B according to a second embodiment of the present invention. In Figure 2, 1 is a tank for an oil-filled electrical device such as a transformer, and 2 is the main body of the electrical device installed in tank 1. The main body of the electrical device 2 consists of a coil 2a, an iron core 2b, etc., and is immersed in insulating oil 3 filled in tank 1.

[0060] Reference numeral 4a denotes a filtering device connected to the inside of the tank 1 by oil supply pipes 5e to 5g, and reference numerals 6a and 6b denote filters each containing a different adsorbent. As the adsorbent, known adsorbents (such as clay or activated alumina) can be used.

[0061] Reference numeral 7 denotes a heater that heats the insulating oil flowing through pipe 9 in filtration device 4a to a predetermined temperature (for example, 40°C), and 8 denotes a pressure gauge that measures the dynamic pressure of the insulating oil flowing through pipe 9. Reference numeral 10 denotes a pump that causes the insulating oil to flow through pipe 9, and 11a denotes a valve installed on pipe 9 between filters 6a, 6b and heater 7.

[0062] Reference numeral 12 denotes a measuring instrument consisting of a conductivity meter or a dielectric constant meter, etc., installed on the oil supply pipe 5c which is connected to the oil supply pipes 5e to 5g, 13c denotes a valve installed on the oil supply pipe 5e, 13d denotes a valve installed on the oil supply pipe 5f, and 13e denotes a valve installed on the oil supply pipe 5g.

[0063] Reference numeral 14a denotes an oil supply pipe for supplying insulating oil 3 in tank 1 of oil-filled electrical equipment, and 15 denotes a new oil tank for storing unused insulating oil (new oil) 3a. Reference numeral 16 denotes an oil supply pipe for supplying new oil 3a in new oil tank 15, and 17 denotes a valve installed on oil supply pipe 16.

[0064] Reference numeral 18 denotes a valve for allowing the insulating oil 3 flowing through the oil supply pipe 14a or new oil flowing through the oil supply pipe 16 to flow into the oil supply pipe 14b, and 19 denotes an oil treatment tank for storing the insulating oil 3b that has been degassed. Reference numeral 20 denotes a nozzle attached to the tip of the oil supply pipe 14b that passes through the oil treatment tank 19 from the top, and 21 denotes a vacuum pump for reducing the pressure inside the oil treatment tank 19.

[0065] Reference numeral 22 denotes a valve that is opened when the vacuum pump 21 reduces the pressure inside the oil treatment tank 19, and 23 denotes a pressure gauge for measuring the pressure inside the oil treatment tank 19. The pressure gauge 23 is used to manage the pressure inside the oil treatment tank 19 that is being reduced in pressure by the vacuum pump 21.

[0066] Reference numeral 24 denotes an oil inflow prevention unit installed in the oil treatment tank 19, which prevents insulating oil 3b from flowing into the vacuum pump 21 when the pressure inside the oil treatment tank 19 is reduced by the vacuum pump 21. The structure of the oil inflow prevention unit 24 is the same as that of the insulating oil recycling treatment device A in Fig. 1. Reference numeral 25 denotes a valve for returning the pressure inside the oil treatment tank 19 to atmospheric pressure.

[0067] Reference numeral 26 denotes a discharge pipe connected to the lower drain of the oil treatment tank 19, and 27 denotes a valve installed on the discharge pipe 26. Reference numeral 28 denotes a waste oil pipe that communicates with the discharge pipe 25 by switching a valve 29, and by switching the valve 29, the insulating oil 3b flowing through the discharge pipe 26 can be made to flow into the oil supply pipe 5d or into the waste oil pipe 28. Reference numeral 30 denotes a waste oil tank for receiving the insulating oil 3b discharged through the waste oil pipe 28.

[0068] Next, we will explain the operation of the insulating oil reclamation treatment device B. The operation of the reclamation treatment device B is also controlled by a control unit (not shown). When the insulating oil in an oil-filled electrical device is to be reclaimed or replaced with new oil, oil feed pipe 14a is inserted into tank 1, and valve 18 is switched to connect the inside of tank 1 to the inside of oil treatment tank 19 via oil feed pipes 14a and 14b.

[0069] In this state, valve 22 is opened and vacuum pump 21 is driven to suck up insulating oil 3 in tank 1 through oil feed pipes 14a and 14b. The sucked up insulating oil 3 is sprayed from nozzle 20 in the form of a shower or mist into oil treatment tank 19. The umbrella portion 24b of oil inflow prevention portion 20 prevents insulating oil 3 sprayed from nozzle 20 from entering bottomed semi-cylindrical portion 20a. Moisture and decomposition gases are removed from insulating oil 3 sprayed in the form of a shower or mist, and the oil is stored in oil treatment tank 19.

[0070] Next, with the valve 18 closed, the vacuum pump 21 is driven to reduce the pressure inside the oil treatment tank 19 to a predetermined pressure. The predetermined pressure is managed by the pressure gauge 23.

[0071] When the pressure is reduced, the insulating oil 3b in the oil treatment tank 19 can be reliably prevented from flowing into the vacuum pump 21 by the oil inflow prevention unit 24. By reducing the pressure inside the oil treatment tank 19 to a predetermined level, the moisture and decomposition gas contained in the insulating oil 3b in the oil treatment tank 19 can be further removed.

[0072] After the degassing process, the insulating oil 3b is passed through the discharge pipe 26 and the oil supply pipe 5d by the valve 29 while the valves 25 and 27 are open and one of the valves 13c to 13e is also open. By driving the pump 10 of the filtering device 4a, the insulating oil 3b flows from the discharge pipe 26 through the oil supply pipe 5d and into the pipe 9 of the filtering device 4a.

[0073] In the filtration device 4a, the dynamic pressure of the insulating oil 3b flowing through the pipe 9 is measured by a pressure gauge 8, and the insulating oil 3b is heated to a predetermined temperature (40°C) by a heater 7. The heated insulating oil 3b flows to the oil supply pipe 5g, the filter 6b, or the filter 6a depending on the switching operation of the valve 11a.

[0074] When the insulating oil 3b flows into the oil supply pipe 5g, the degree of deterioration of the insulating oil 3b is measured by the measuring instrument 12 on the oil supply pipe 5c, and then the insulating oil 3b is supplied into the tank 1. In this case, the insulating oil 3b in the tank 1 is degassed in the oil treatment tank 19 and returned to the tank 1.

[0075] When the oil flows to the filter 6b, solids such as carbon and sludge are removed by an adsorbent (for example, clay) in the filter 6b. The insulating oil 3b that has passed through the filter 6b has its degree of deterioration measured by a measuring instrument 12 on the oil supply pipe 5c, and is then fed into the tank 1. In this case, the insulating oil 3 in the tank 1 is returned to the tank 1 after being degassed in the oil treatment tank 19 and regenerated by filtration in the filter device 4a.

[0076] When the oil flows into the filter 6a, solid matter such as carbon and sludge is removed by an adsorbent (for example, activated alumina) in the filter 6a. The insulating oil 3b that has passed through the filter 6a has its degree of deterioration measured by a measuring instrument 12 on the oil supply pipe 5c, and is then fed into the tank 1. In this case, the insulating oil 3 in the tank 1 is returned to the tank 1 after being degassed in the oil treatment tank 19 and regenerated by filtration in the filtration device 4a.

[0077] When the insulating oil 3b is passed through the filters 6a and 6b, the heater 7 heats the insulating oil 3b to a temperature that increases the adsorption efficiency of the adsorbent. Therefore, when the insulating oil 3b is not passed through the filters 6a and 6b, there is no need to heat the insulating oil 3b with the heater 7.

[0078] In this way, the degree of deterioration of the insulating oil 3 in the tank 1 is improved by passing it through the oil treatment tank 19 and the filtration device 4a, and it can be returned as recycled oil to the tank 1. By repeating this recycling process, the measurement value by the measuring instrument 12 on the oil supply pipe 5c improves.

[0079] The filters 6a and 6b that make up the filtration device 4a become clogged with the accumulation of solid matter such as carbon and sludge as a result of repeated filtration. When this occurs, the dynamic pressure of the insulating oil 3b measured by the pressure gauge 8 on the pipe 9 rises, and the time to replace the filters 6a and 6b can be determined from the reading of the pressure gauge 8. It is also possible to configure the system to make it easier for the manager to manage, for example, by linking the pressure gauge 8 to light up a lamp to indicate when it is time to replace the filter 6.

[0080] The insulating oil recycling treatment device B shown in Figure 2 can also mix new oil 3a and return it to the tank 1 during the process of recycling the insulating oil 3 in the tank 1. In this case, around the time of sending oil from the tank 1 to the oil treatment tank 19, the valve 17 on the oil supply pipe 16 is opened, and the vacuum pump 21 transfers the new oil 3a from the oil supply pipe 16 through the oil transfer pipe 14b and the nozzle 20 into the oil treatment tank 19. The umbrella portion 24b of the oil inflow prevention unit 20 prevents the new oil 3a transferred from the nozzle 20 into the bottomed semi-cylindrical portion 24a. Inside the oil treatment tank 19, the insulating oil 3 transferred from the tank 1 and the new oil 3a in the new oil tank 15 are mixed together.

[0081] The process of returning the mixed insulating oil 3b through the filtration device 4a into the tank 1 is the same as that described above, so a detailed explanation will be omitted. The insulating oil 3b, which is a mixture of the insulating oil 3 and the new oil 3a, has a dramatically improved degree of deterioration, and the measurement value measured by the measuring instrument 12 also improves.

[0082] If the insulating oil 3 in the tank 1 has deteriorated so much that it cannot be regenerated by the above-mentioned regeneration process, the insulating oil 3 in the tank 1 can be discarded and only new oil 3a can be poured into the tank 1. When pouring only new oil 3a into the tank 1, first, the valve 18 is switched to connect the inside of the tank 1 to the inside of the oil treatment tank 19.

[0083] In this state, the valve 22 is opened and the vacuum pump 21 is driven to suck up the insulating oil 3 in the tank 2 through the oil transfer pipes 14 a and 14 b and transfer the insulating oil 3 from the nozzle 20 into the oil treatment tank 19 .

[0084] The insulating oil 3b stored in the oil treatment tank 19 is discharged from the discharge pipe 26 through the waste oil pipe 28 to the waste oil tank 30 by opening the valves 25 and 27 and switching the valve 29 to connect the discharge pipe 26 and the waste oil pipe 28.

[0085] Next, with valves 25 and 27 closed and valve 17 open, pump 21 is driven to store new oil 3a in new oil tank 15 in oil treatment tank 19. Once new oil 3a has accumulated in oil treatment tank 19, valve 18 is switched to connect oil supply pipe 16 to oil transfer pipe 14b. Valve 29 is then switched to connect discharge pipe 26 to oil supply pipe 5d.

[0086] Next, valve 27 is opened, and with one of valves 13c to 13e open, pump 10 of filtration device 4a is driven, thereby injecting new oil 3a from inside oil treatment tank 19 into tank 1 through discharge pipe 26, oil supply pipe 5d, pipe 9 of filtration device 4a, oil supply pipes 5e to 5g, and 5c.

[0087] The new oil 3a may be returned to the tank 1 through the filter 6a (6b) after being heated by the heater 7, or may be returned to the tank 1 through the oil supply pipe 5g without being heated by the heater 7.

[0088] The operation of the insulating oil reclamation treatment device B can also be performed automatically or semi-automatically. For example, if the measurement by the measuring device 12 shows that the insulating oil is not very deteriorated, the various valves and pumps are controlled so that filtration by the filter 6a (6b) is not performed and only degassing treatment is performed in the oil treatment tank 19.

[0089] If the insulating oil is severely deteriorated, the various valves and pumps are controlled to perform both selection and filtration in the filter 6a (6b) and degassing in the oil treatment tank 19. Alternatively, the deteriorated state of the insulating oil 3 in the tank 1 may be resolved by controlling the various valves and pumps to mix the insulating oil 3 in the tank 1 with the insulating oil in the new oil tank 15 and return the mixture to the tank 1.

[0090] If the insulating oil is severely deteriorated and cannot be recycled, the insulating oil 3 is discharged to a waste oil tank 30, and various valves and pumps are controlled to feed only new oil 3a into the tank 1. Naturally, all or part of the control of such various valves and pumps may be manually operated.

[0091] 2 has been described as a case where the oil inflow prevention unit 24 is attached to the oil treatment tank 19, but the vacuum pump 21 and valve 22 may be attached at the positions shown by the dotted lines in Fig. 2, and the insulating oil 3b may be prevented from flowing into the vacuum pump 21 by drawing a vacuum from the top of the oil treatment tank 19. With this configuration, the oil inflow prevention unit 24 is not required, as in the insulating oil recycling treatment device A shown in Fig. 1.

[0092] Furthermore, insulating oil regeneration treatment device B is configured to be able to select and filter filters 6a and 6b containing the most suitable adsorbent according to the measurement value from measuring device 12. While Fig. 2 illustrates a case where two filters 6a and 6b are provided, the number of filters constituting the present invention is not limited to two, and the device may be configured with more than two filters. By installing additional valves downstream of valve 11a according to the number of filters, it is possible to accommodate a large number of filter options.

[0093] In the above-mentioned first and second embodiments, the deterioration degree of the insulating oil is measured by a measuring instrument, but the deterioration state may be determined from the color of the insulating oil sampled from the tank 1 of the oil-filled electrical equipment. In this case, the control of various valves and pumps according to the deterioration degree of the insulating oil is semi-automated.

[0094] Furthermore, the order of operation of the various valves and pumps is not limited to the order described above, and it goes without saying that the order of operation may be changed as long as the contents of the present invention can be realized. Furthermore, although the various valves are shown with a single symbol in Figures 1 and 2, they do not have to be single valves, and the various valves may be configured by combining multiple valves so as to realize the above functions.

[0095] Furthermore, the deterioration state of the insulating oil is not limited to the values ​​measured by the conductivity meter or dielectric meter described above, but may also be measured based on one or more physical property values ​​of the insulating oil, such as kinematic viscosity, density, turbidity, transmittance, volume resistivity, dielectric loss tangent, surface tension, acid value, breakdown voltage, moisture content, and flash point.

[0096] As described above, the insulating oil regeneration treatment device of the present invention makes it possible to select between regeneration and waste oil depending on the deterioration state of the insulating oil.

[0097] Furthermore, when the inside of the oil treatment tank is evacuated by the vacuum pump, the insulating oil in the oil treatment tank can be reliably prevented from flowing into the vacuum pump.

[0098] Furthermore, by measuring the physical properties of insulating oil, such as its conductivity, hue, dielectric constant, and electrical conductivity, it is possible to accurately grasp the state of deterioration of the insulating oil and control valves and pumps according to the measured values.

[0099] Furthermore, the adsorbent provided in the filter can reliably remove the degradation products contained in the insulating oil, and by adjusting the temperature of the insulating oil with a heater, the efficiency of the adsorbent in removing the degradation products can be increased.

[0100] Furthermore, the filters may be configured to contain different adsorbents, making it possible to select the filter through which the insulating oil to be regenerated passes.

[0101] Furthermore, the dynamic pressure of the insulating oil flowing inside the piping can be measured using a pressure gauge, so the clogging of the filter can be determined from the pressure gauge measurement results, making it easy to determine when the filter needs to be replaced. [Industrial Applicability]

[0102] It can be applied to the regeneration / disposal of insulating oil in oil-filled electrical equipment. [Explanation of symbols]

[0103] 1 tank 2 Electrical equipment body 2a coil 2b Iron core 3, 3b Insulating oil 3a insulating oil (new oil) 4, 4a Filtration device 5a, 5b, 5c, 5d, 5e, 5f, 5g Oil supply piping 6, 6a, 6b filters 7 Heater 8, 23 Pressure gauge 9, 9a Piping 10 Pump 11, 11a, 13a, 13b, 13c, 13d, 13e, 17, 18, 22, 25, 27, 29 valves 12 Measuring instruments (conductivity meters, dielectric meters, etc.) 14a, 14b Oil supply pipes 15 New oil tank 16 Oil supply pipe 19 Oil treatment tank 20 nozzles 21 Vacuum pump 24 Oil inflow prevention part 24a Bottomed semi-cylindrical part 24b Umbrella section 26 Discharge piping 28 Waste oil piping 30 Waste oil tank A, B Insulating oil regeneration treatment equipment

Claims

1. An insulating oil regeneration method characterized by measuring the deterioration state of insulating oil in oil-filled electrical equipment, selecting a method for regenerating the insulating oil or selecting disposal of the insulating oil depending on the measurement results, and switching the oil transport route for the insulating oil depending on the selection results.

2. The insulating oil regeneration method according to claim 1, characterized in that the regeneration method allows the user to select whether to add degassing to the degassing process by degassing the insulating oil in the tank to which the insulating oil is transferred and filtering the insulating oil through a filter.

3. The insulating oil regeneration method according to claim 1, characterized in that the degassing is performed by drawing a vacuum from the upper position of the tank using a vacuum pump, or by drawing a vacuum using a vacuum pump through an oil inflow prevention means installed on the inner surface of the tank, thereby preventing the insulating oil in the tank from flowing into the vacuum pump.

4. 3. The method for regenerating insulating oil according to claim 1, wherein the deterioration state of the insulating oil is measured based on one or more physical property values ​​of the insulating oil, including hue, electrical conductivity, dielectric constant, kinematic viscosity, density, turbidity, transmittance, volume resistivity, dielectric dissipation factor, surface tension, acid value, breakdown voltage, moisture content, and flash point.

5. The insulating oil regeneration method according to claim 2, characterized in that the filter that filters the insulating oil is provided with an adsorbent, and the insulating oil that passes through the filter is heated to a temperature at which the adsorption effect of the adsorbent is enhanced.

6. 6. The insulating oil regeneration method according to claim 5, wherein a plurality of filters are installed, each filter having a different adsorbent, and it is possible to select which of the filters the insulating oil is passed through.

7. 6. The insulating oil regeneration method according to claim 5, further comprising the step of: providing a pressure gauge for measuring the pressure in the pipe through which the insulating oil is transported; determining whether the filter is clogged based on the measurement results of the pressure gauge; and determining when the filter should be replaced.

8. An insulating oil regeneration treatment device characterized by comprising a control unit that measures the deterioration state of insulating oil in oil-filled electrical equipment, selects a method of regenerating the insulating oil or selects disposal of the insulating oil depending on the measurement result, and switches the oil transport route of the insulating oil depending on the selection result.

9. The insulating oil regeneration treatment device according to claim 8, characterized in that the control unit can select, as a regeneration method, whether to degas the insulating oil in a tank to which the insulating oil has been transferred or to filter the insulating oil in addition to the degassing.

10. 9. The insulating oil recycling treatment device according to claim 8, wherein the degassing is performed by drawing a vacuum from the upper position of the tank with a vacuum pump, or by drawing a vacuum with a vacuum pump through an oil inflow prevention means installed on the inner surface of the tank, thereby preventing the insulating oil in the tank from flowing into the vacuum pump.

11. 11. The insulating oil regeneration treatment device according to claim 10, wherein the oil inflow prevention means comprises a bottomed semi-cylindrical portion having an opening at the top, and a cap portion located above the opening.

Images