Proving Test on Removal of PCB from Pole Transformer by Solvent Cleaning Method

Examination of Transaction Method by Residual Insulation Oil

Abstract

In order to establish a method of disposing a trace of PCB contained in reclaimed insulating oil in pole transformers (50 mg PCB/kg or less) in a safe manner, a full-scale insulating oil removal test by means of solvent cleaning was conducted using a real transformer not containing PCB. Test conditions were determined to prepare for the decontamination test for transformers containing PCB, and safety of the facilities was confirmed. Major results obtained are shown as follows:
(1) Satisfactory removal performance was obtained by breaking the transformer with the low-temperature crushing technique and sorting the members for cleaning.
(2) It was estimated that residual PCB in ferrous materials, copper materials and ceramics could be redacted to the level below a preset limit after primary cleaning of five minutes and secondary cleaning of ten minutes, and that inpieces of paper and wooden chips could be reduced to the level of 0.1 mg PCB/kg members or below after primary cleaning of 60 minutes and secondary cleaning of 600 minutes or less.
(3) It was confirmed that the facilities could be operated safely, and enviromental and working safety could be ensured.