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EP0186291A1 Expired / Lapsed EP ⏱️ 0.0 years remaining

Decontamination of insulating fluids

Assignee: Micanite & Insulators Co Ltd
•
Filing: 1985-11-11
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Granted: —
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Expires: 2005-11-11
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Abstract

Abstract Contaminated insulating liquid from a transformer or similar electrical apparatus is passed through a degasifier (1), to a thin-film evaporator (2) where trichlorobenzenes (T.C.B.'s) are removed and thence to a molecular still (3) where polychlorobyphenyls (P.C.B.'s) are distilled off and condensed in a cold trap (8). The apparatus is typically 2.5m high, and is thus transportable to the site of a contaminated transformer or the like.

Inventors

  • 👤 Hugh Malcolm Worthington
  • 👤 Christopher William Livesey

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-10-26 05:57
CPC Classifications
C; C10; C10G; C10G7/00; C10G7/006; B; B01; B01D; B01D3/00; B01D3/12

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 31 words
A method of removing polychlorobiphenyl contaminants from essentially non-volatile insulating fluid wherein the contaminated insulating fluid is subjected to a molecular distillation process so as to distil off the polychlorobiphenyl contaminants.
Claim 2
Independent Claim 31 words
A method of removing polychlorobiphenyl contaminants from essentially non-volatile insulating fluid wherein the contaminated insulating fluid is subjected to a molecular distillation process so as to distil off the polychlorobiphenyl contaminants.
Claim 3
Dependent Claim 25 words
A method according to Claim 1 wherein said fluid is formed into a heated liquid film which film is wiped during said molecular distillation process.
Claim 4
Dependent Claim 14 words
A method according to Claim 2 wherein said film is wiped by rolling action.
Claim 5
Independent Claim 31 words
A method according to any preceding Claim wherein the contaminated insulating fluid is initially fed through a low pressure evaporator to remove components which are more volatile than the polychlorobiphenyl contaminants.
Claim 6
Dependent Claim 16 words
A method according to Claim 4 wherein said low pressure evaporator is a thin film evaporator.
Claim 7
Dependent Claim 27 words
A method according to Claim 4 or Claim 5 wherein the pressure, as measured over a cold trap, in said low pressure evaporator is below 10 Torr.
Claim 8
Independent Claim 32 words
A method according to any preceding Claim wherein the molecular distillation process is carried out at a pressure, as measured over a cold trap, of between 10 -3 and 10 -4 Torr.
Claim 9
Independent Claim 14 words
A method according to any preceding Claim wherein said fluid comprises an organic ester.
Claim 10
Independent Claim 23 words
A method according to any preceding Claim wherein the contaminated insulating fluid is passed continuously through molecular distillation apparatus at a controlled rate.
Claim 11
Dependent Claim 15 words
Electrical apparatus containing insulating fluid decontaminated by a method in accordance with any preceding Claim.
Claim 12
Dependent Claim 47 words
Apparatus arranged to remove polyphlorobiphenyls from an insulating liquid, said apparatus comprising a degasifier, an evaporator for removing components of the liquid which are highly volatile, said evaporator being connected to the outlet of the degasifier, and a molecular still connected to the outlet of the evaporator.
Claim 13
Dependent Claim 47 words
Apparatus arranged to remove polyphlorobiphenyls from an insulating liquid, said apparatus comprising a degasifier, an evaporator for removing components of the liquid which are highly volatile, said evaporator being connected to the outlet of the degasifier, and a molecular still connected to the outlet of the evaporator.
Claim 14
Independent Claim 32 words
A method of removing polychlorobiphenyl contaminants from volatile insulating fluid wherein the contaminated insulating fluid is subjected to a molecular distillation process so as to distill it off from the polychlorobiphenyl contaminants.
Claim 15
Independent Claim 32 words
A method of removing polychlorobiphenyl contaminants from volatile insulating fluid wherein the contaminated insulating fluid is subjected to a molecular distillation process so as to distill it off from the polychlorobiphenyl contaminants.

References Cited (Backward Citations)

GB415088A Cited
GB1485577A Cited
US4333822A Cited

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