CN101506916A - A method of treating copper sulphide deposits in an electrical apparatus by the use of oxidising agents - Google Patents

A method of treating copper sulphide deposits in an electrical apparatus by the use of oxidising agents Download PDF

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Publication number
CN101506916A
CN101506916A CNA2007800315300A CN200780031530A CN101506916A CN 101506916 A CN101506916 A CN 101506916A CN A2007800315300 A CNA2007800315300 A CN A2007800315300A CN 200780031530 A CN200780031530 A CN 200780031530A CN 101506916 A CN101506916 A CN 101506916A
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China
Prior art keywords
oxidant
equipment
electric equipment
electric
gas
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CNA2007800315300A
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Chinese (zh)
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K·古斯塔夫森
R·利安德森
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ABB Research Ltd Switzerland
ABB Research Ltd Sweden
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ABB Research Ltd Switzerland
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Publication of CN101506916A publication Critical patent/CN101506916A/en
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B3/00—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties
    • H01B3/18—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances
    • H01B3/20—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances liquids, e.g. oils
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01B—CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES
    • H01B3/00—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties
    • H01B3/18—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances
    • H01B3/48—Insulators or insulating bodies characterised by the insulating materials; Selection of materials for their insulating or dielectric properties mainly consisting of organic substances fibrous materials
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F27/00—Details of transformers or inductances, in general
    • H01F27/34—Special means for preventing or reducing unwanted electric or magnetic effects, e.g. no-load losses, reactive currents, harmonics, oscillations, leakage fields

Abstract

A method of treating copper sulphide deposits on materials and surfaces that are in contact with electrically insulating oil inside an electrical apparatus, wherein a substantial amount of the electrically insulating oil, normally present in said electrical apparatus, have been removed. The copper sulphide is subjected to treatment with an oxidizing agent which causes a reaction with the copper sulphide deposits. The oxidizing agent can comprise any compound from the list; chlordioxide, a peroxy acid or ozone.

Description

Use oxidant in electric equipment, to handle the method for copper sulphide deposits
Technical field
The present invention relates to the method for the copper sulphide deposits that occurs in the electric insulation layer of a kind of processing in electric equipment.
Background technology
In electric power transfer and power field, in multiple distinct device, use insulating oil, described multiple distinct device is power transformer, distribution transformer, tap change, switchgear and reactor for example.Insulating oil is the mineral oil of height refining normally, and insulating oil is stable and have an outstanding electric insulation attribute when high temperature.The function of oil is in equipment conductor to be carried out electric insulation, suppresses corona and electric arc, and is used as the cooling fluid of conductor in electric equipment.
These electric insulation oils comprise traces of reactive sulphur compounds usually, for example, mercaptan (being also referred to as mercaptan mercaptan), mercaptan can and form copper mercaptide with copper or cupric oxide reaction.Copper mercaptide can further decompose, and causes forming copper sulfide (I) Cu 2S.
A reaction path illustrates as follows:
Cu 2O+2RSH＝>2Cu?SR+H2O
2CuSR＝>Cu2S+RSR
Wherein RSH is a mercaptan, and-SH is mercapto (perhaps mercaptan mercaptan), and-R is that alkyl and RSR are thioethers.Other sulfuration organic substance (especially sulfide) also can enliven, and perhaps directly reacts with copper, perhaps reacts with copper via being converted into mercaptan.
Copper sulfide can not dissolve in oil, and can form deposit on surface that inside electric appliance contacts with electric insulation oil and material.For example, although paper, timber and oil used more than 100 year, big power transformer winding is still mostly insulated by these materials, and these materials still provide good sexual valence balance.
Copper sulfide is the semiconductor of electricity, and forms degeneration or interruption that the semiconductive deposit can cause operation of equipment on surface in electric equipment and the material.
If deposited semi-conductive copper sulfide on the insulating material that is used for coating electrical equipment copper conductor (normally for example the cellulosic material of paper), then this may cause the insulation attribute of insulating material to be degenerated, and this will cause electric leakage or short circuit.The solid insulating material of inside electric appliance (such as, timber, pottery and compacting version) lip-deep semiconductor sulfuration copper deposit also can cause similar problem.
The semiconductor sulfuration copper deposit that directly is deposited on the conductive surface will cause a lot of problems, especially when formation is sedimental on the connector surface.
In CIGRE Moscow symposium 2005, " the Oil corrosion and Cu that delivers by people such as Bengtsson 2S deposition In Power Transformers " literary composition described result and the surface in power transformer and the copper sulfide Cu on the material of the analysis of failure 2S reproduces in sedimental laboratory.
The WO 2005115082 that name is called " Method for removing reactive sulfur from insulating oil " has described a kind of method that is used for removing from insulating oil sulfur-containing compound, and this method realizes by insulating oil being exposed at least a sulphur cleaning of substances and insulating oil being exposed at least a polar adsorbent.
Method in WO 2005115082 is to develop at following purpose: be used for by removing the sulfur-containing compound at the oil of electric equipment outside, and handle the electric insulation oil in electric equipment, existed, it prevents that copper sulfide from continuing deposition on the material of inside electric appliance and surface.Up to now, not about how handling the suggestion of the copper sulphide deposits that on the surface of inside electric appliance and material, has deposited.Current, the scheme that only has of removing the copper sulphide deposits on the insulating paper that is used for the covering copper conductor is to remove old paper and it is replaced with new insulating paper.
JP 2001311083 has described: use before the electric insulation oil in electric equipment, oil is stored in the container that comprises copper or copper alloy, remove the method for the sulphur compound in electric insulation oil.Sulphur compound in the oil can react with copper, and catches this sulphur compound thus, and before using in electric equipment it is removed from oil.
Summary of the invention
An embodiment of the invention provide a kind of method, and the material and the lip-deep semiconductor that utilize oxidant to handle at inside electric appliance by means of this method vulcanize copper deposit, have wherein removed a large amount of insulating oils in the electric equipment.
An embodiment of the invention realize by means of the method for original definition, it is characterized in that: oxidant with react at the material and the lip-deep described copper sulphide deposits of inside electric appliance, and described reaction is converted to more nonconducting compound with copper sulphide deposits.Copper sulfide is semiconductor and forms the insulation attribute that semiconductor deposit will cause reducing insulating material and insulating oil system that on insulating material this will cause short circuit in electric equipment.Can avoid short circuit by removing copper sulfide from insulating material or copper sulfide being converted to the compound that has than low electric conductivity.
In an embodiment of the invention, described oxidant comprises chlorine dioxide ClO 2
In another embodiment of the present invention, described oxidant comprises peroxy acid R-O 3H.
In another embodiment of the present invention, described peroxy acid comprises peracetic acid C 2H 4O 3
In another embodiment of the present invention, described peroxy acid comprises performic acid CH 2O 3
In another embodiment of the present invention, described oxidant comprises ozone O 3
In will comprising of inside electric appliance: paper, compacting version, timber and other solid-state/fibroid insulating material that contact with electric insulation oil by the material that this method is handled.
In will comprising of inside electric appliance: the conductor of insulation, the conductor of exposure, magnetic core and other solid state surfaces that contact with electric insulation oil by the surface that this method is handled.
Method according to an embodiment of the invention provide further may further comprise the steps: before utilizing described oxidizer treatment, utilize displacer that described copper sulphide deposits is carried out preliminary treatment.
Described displacer and copper sulphide deposits react, and copper sulfide is converted to easier material by the oxidant oxidation.The example of displacer is the elemental halogen element, especially iodine I 2Perhaps chlorine Cl 2
According to an embodiment of the invention, before utilizing oxidizer treatment, remove whole remaining oil, and further clean described inside electric appliance by means of the liquid of the described electric insulation oil of solubilized wherein.
Can carry out this method but on surface and material, remained some oily electric equipment to wherein having removed most of oil.Response preparation, oxidant and possible displacer both, with the gas form access arrangement, and be absorbed in the oil on surface or material/dissolve then, and mainly in oily attitude, react.
Can also carry out this method to following electric equipment: in this equipment, removed most of oil, and utilized solvent further all material and the surface of device interior to be cleaned then.Can remove described solvent then by utilizing solvent that device interior is sprayed or cleaning to carry out electric equipment is cleaned by solvent.Can also carry out equipment is cleaned by introducing solvent in the steam mode and making described vapor condenses on surface and material.Then, remove coagulation in the slave unit.
Another embodiment of the present invention is the system of a kind of processing at the material and the lip-deep copper sulphide deposits of inside electric appliance, described material and surface contact with the common electric insulation oil that exists in the described electric equipment, oil in the wherein said electric equipment is almost sky, and described system comprises the device that is used for gaseous chemical agent is introduced described electric equipment, and described system comprises and is used for device that excess air is removed from described electric equipment.In described system, the described device that is used to introduce gaseous chemical agent is included in the source of chemicals and the interim connection between the described equipment.Described gaseous chemical agent can be the oxidant that comprises chlorine dioxide, peracetic acid, performic acid, ozone, or comprises the displacer of iodine or chlorine.
According to an embodiment of the invention, in controlled gas, carry out described processing.The parameter of the content by control example such as humidity, temperature, oxidant concentration or local pressure, nitrogen and oxygen is come control gaseous.
If exist to use displacer to come copper sulphide deposits is carried out pretreated step, then the parameter of the content by control example such as humidity, temperature, oxidant concentration or local pressure, nitrogen and oxygen is come control gaseous.
In order to react the local pressure of necessary control appliance internal gas in a controlled manner.Need the gas of emphasis control to be: oxidant or displacer, nitrogen, oxygen and humidity.This method may need to utilize for example nitrogen N 2The nonreactive gas step of diluting oxidant or displacer.This method can be included in before the gas injection equipment, admixture of gas is watered down the step of (dying).
Reactivity also is subjected to Temperature Influence in the equipment, and a kind of control appliance method of temperature that is used for is, the electric current of utilization by conductor heats the conductor in the electric equipment, and method of temperature is in the another kind of control appliance, the external heater on the use equipment.
In order to react with sufficient reactivity, a large amount of gases that preparation (oxidant or displacer) must slave unit inside are sent to surface and material.In order to ensure the transmission of preparation, gas must fully mix.A kind of mode of mixing apparatus gas inside is, utilizes the mixing arrangement of placing at inside electric appliance, for example, and fan, blender or pump.And the another way of mixing apparatus gas inside is, extracts the portion gas in the described electric equipment, and it is presented back described electric equipment, promptly utilizes circulation cycle.
After reacting with copper sulfide, product is non-conductive copper sulphate mostly, allow this product to be retained on the material and surface of electric equipment, and this electric equipment is refilled electric insulation oil, and ready being used to reuses.
Along with preparation (oxidant or displacer) is fed in the equipment, must remove the gas of equivalent to prevent overvoltage in the slave unit.The gas of being removed comprises the unreacted preparation of some, and does not allow described unreacted preparation to enter outside atmosphere.Thus, this method comprises the step (by preparation being converted to the material of less activity) that the unreacted preparation is removed and destroyed.For example, under the situation of oxidant, the gas of removing is undertaken by being easy to oxidized material.If the gas of removing comprises displacer iodine I 2, then can in condenser pipe (cold trap), catch iodine.
Description of drawings
Accompanying drawing constitutes the part of this specification, and comprise can accomplished in various ways illustrative embodiments of the present invention.Should be appreciated that, under some example, can exaggerate, simplify or enlarge various aspects of the present invention, so that understand the present invention.
Fig. 1 is the flow chart of an embodiment of the invention;
Fig. 2 shows the schematic process diagram of one embodiment of the present invention; And
Fig. 3 shows another schematic process diagram of one embodiment of the present invention.
Embodiment
Provide the detailed description of preferred implementation at this.Yet, should be appreciated that, can accomplished in various ways the present invention.Thus, it is restriction that specific detail disclosed herein is not annotated, but as the basis of claims and as the basis of representing, is used for instructing those skilled in the art in any suitable detailed system, structure or the actual use of mode the present invention.
Fig. 1 shows the schematic process diagram of method.In square frame 1, from electric equipment, remove electric insulation oil.Square frame 2 is optional steps, in order to the device interior that holds electric insulation oil is cleaned, for example, by utilizing solvent that inside electric appliance is sprayed or cleaning, perhaps by removing oil/solvent solution then at device interior coalescent solvent steam.
Square frame 3 is optional steps, in order to utilize displacer material in the electric equipment and lip-deep copper sulphide deposits is carried out preliminary treatment, so that help oxidation reaction, a kind of example of possible displacer is iodine steam or hydrogenation iodine.
Square frame 4 is oxidation reactions (processing) of the copper sulfide that occurs on material and surface.This reaction will be in electric equipment material and lip-deep semiconductor sulfuration copper to be converted to mainly be non-conductive copper sulphate.Oxidant is fed to the electric equipment from square frame 6, and in square frame 7, unreacted oxidant is destroyed.
The example of the possible oxidant that can also use is ClO 2, ozone or peracetic acid.
Processing is finished in square frame 5, and electric equipment is full of electric insulation oil, and is used to put into operation once more.
Fig. 2 shows the flow chart of an embodiment of the invention.In this flow chart, before handling, from electric equipment 10, removed oil, and handled and to begin.Oxidant storage or generating apparatus 11 are supplied with necessary oxidant with gas form, are used to react.Oxidant is fed 15 to electric equipment 10, wherein comes control gaseous at for example parameter of the content of humidity, temperature, oxidant concentration, nitrogen and oxygen.
The example of the possible oxidant that can also use is ClO 2, ozone or peracetic acid.
If oxidant is ClO 2, then must control procedure, thus make generate or storage device in and at the ClO of inside electric appliance 2The concentration percent by volume be no more than 15%, this is because when surpassing this concentration, ClO 2Chlorine and oxygen will be decomposed into explosively.
Gas in the electric equipment 10 must mix, so that oxidant diffuses on the material and surface of pending inside electric appliance, is sufficient so that guarantee reactivity.In a kind of possibility that gas is mixed shown in the flow chart be, at electric equipment 10 inner internal mixer or the fans 14 of using.Unreacted oxidant and excessive gas are removed 16 and be fed to destructor (destructor) 12, and it removes remaining oxidant or reaction with it, and the byproduct 17 of harmless only.
If utilize displacer to material in the electric equipment with lip-deep copper sulphide deposits carries out preliminary treatment so that oxidation reaction, then flow chart comprises substitution agent storage means 18, and it realizes displacement reaction in order to supply with necessary displacer with gas form.Valve gear 19 is in order to select which kind of preparation is injected electric equipment 10.
Fig. 3 shows the flow chart of an embodiment of the invention.In this flow chart, from electric equipment 20, removed oil, and begun to handle.Oxidant storage or generating apparatus 11 are supplied with necessary oxidant and are used to react.Oxidant presents 25 to circulation cycle 28, and this circulation cycle 28 is used for oxidant is mixed with the gas of device interior.Come the gas in the electric equipment 20 is controlled at for example parameter of humidity, temperature, oxidant concentration, nitrogen and oxygen content.
Gas in the electric equipment 10 must mix, so that oxidant diffuses on the material and surface of pending inside electric appliance, is sufficient so that guarantee reactivity.In a kind of possibility that gas is mixed shown in the flow chart is the circulation cycle 28 with pump 23.Unreacted oxidant and excessive gas are removed 26 and be fed to destructor 22, and it removes remaining oxidant or reaction with it, and the byproduct 27 of harmless only.
If utilize displacer to material in the electric equipment with lip-deep copper sulphide deposits carries out preliminary treatment so that oxidation reaction, then flow chart comprises substitution agent storage means 28, and it is in order to realize displacement reaction with gas form supply 30 to circulation cycle 28 with the displacer of necessity in equipment 20.
Although described the present invention at preferred implementation, it is not intended to scope of the present invention is limited to illustrated particular form; But opposite, be intended to cover this type of that comprise in the spirit and scope of the present invention that limit by appended claims alternative, revise and the equivalence realization.

Claims (28)

1. a processing is in the method for material and lip-deep copper sulphide deposits, and described material and surface contact with the electric insulation oil of inside electric appliance, and a large amount of insulating oil that wherein is in usually in the described electric equipment is removed:
It is characterized in that:
To stand to cause the processing of the oxidant that reacts with described copper sulfide at material and lip-deep described copper sulphide deposits.
2. method according to claim 1 is characterized in that: described oxidant is chlorine dioxide ClO 2
Chlorine dioxide, peroxy acid or ozone.
3. method according to claim 1 is characterized in that: described oxidant comprises peroxy acid.
4. method according to claim 3 is characterized in that: described peroxy acid comprises peracetic acid C 2H 4O 3
5. method according to claim 3 is characterized in that: described peroxy acid comprises performic acid CH 2O 3
6. method according to claim 1 is characterized in that: described oxidant is ozone O 3
7. according to each the described method among the claim 1-6, it is characterized in that: before the processing that utilizes described oxidant, utilize to comprise that the displacer of halogen comes the material and the surface of described electric equipment are handled.
8. method according to claim 7 is characterized in that: described displacer is the elemental halogen element.
9. method according to claim 8 is characterized in that: described displacer comprises iodine I 2
10. method according to claim 8 is characterized in that: described displacer comprises chlorine Cl 2
11. method according to claim 7 is characterized in that: described displacer comprises hydrogen iodide HI.
12. each the described method according among the claim 1-12 is characterized in that: before described processing, remove whole remaining oil, and further clean described inside electric appliance by means of the liquid of the described electric insulation oil of solubilized wherein.
13. each the described method according among the claim 1-12 is characterized in that: in controlled air, carry out the described processing that utilizes described preparation.
14., further comprise nonreactive gas introduced in the described electric equipment to control the step of described gas according to each the described method among the claim 1-12.
15. the method according to described among the claim 1-14 each is characterized in that: during handling, utilize electric current to heat described electric equipment by conductor.
16. the method according to described among the claim 1-14 each is characterized in that: during handling, utilize external heater to heat described electric equipment.
17. according to the method described among the claim 1-16 each, it is characterized in that: during handling, described oxidant is spread in the gas of described inside electric appliance.
18. method according to claim 17 is characterized in that: the mixing arrangement of any kind by being placed on described inside electric appliance is realized the diffusion of oxidant, and the type of described mixing arrangement comprises: fan, blender or pump.
19. method according to claim 17 is characterized in that: the diffusion of described oxidant may further comprise the steps: extract the portion gas in the described electric equipment, and it is presented back described electric equipment, and create turbulent gases in described equipment.
20. according to each the described method among the claim 1-19, it is characterized in that: allow to remain on the material and surface of described inside electric appliance, and described electric equipment has refilled electric insulation oil as the formed copper compound of result that utilizes described oxidant that copper sulfide is handled.
21. each the described method according among the claim 1-20 is characterized in that: will be fed to destructor by remaining unreacted oxidant in described electric equipment, this destructor is converted to more sluggish material with described preparation.
22. a processing is in the system of the material and the lip-deep copper sulphide deposits of inside electric appliance, in the material of described inside electric appliance and surface and the described electric equipment usually the electric insulation oil of existence contact:
It is characterized in that:
Oil in the described electric equipment is almost sky, and described system comprises the device that is used for gaseous chemical agent is introduced described electric equipment, and described system comprises and is used for device that excess air is removed from described electric equipment.
23. system according to claim 22 is characterized in that: the described device that is used to introduce gaseous chemical agent is included in the source of chemicals and the interim connection between the described equipment.
24. according to each the described system among the claim 22-23, it is characterized in that: described gaseous chemical agent can be the oxidant that comprises chlorine dioxide, peracetic acid, performic acid, ozone, or comprises the displacer of iodine or chlorine.
25. according to each the described system among the claim 22-24, it is characterized in that: the described device that is used to remove excess air is included in the interim connection between described equipment and the destructor, and described destructor is used for the composition that enlivens of described equipment gas is converted to more sluggish composition.
26. according to each the described system among the claim 22-25, it is characterized in that: described system comprises the device that is used for nonreactive gas is introduced described equipment.
27. according to each the described system among the claim 22-26, it is characterized in that: described system comprises the device that is used to heat described equipment.
28. each the described system according among the claim 22-27 is characterized in that: described system comprises the device of the described gas that is used for mixing described equipment.
CNA2007800315300A 2006-08-25 2007-08-13 A method of treating copper sulphide deposits in an electrical apparatus by the use of oxidising agents Pending CN101506916A (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
SE06017438 2006-08-25
SE0601743A SE0601743L (en) 2006-08-25 2006-08-25 Procedure for the treatment of an electrical appliance
SE07007487 2007-03-23

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CN101506916A true CN101506916A (en) 2009-08-12

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