Primary alluminiun factory: 8 Rectifier Transformers (Sweden)

Nameplate data of transformers:

Manufact: xxx
Year: 1930
Power [MVA]: 19
Voltage [KV]: 13
Oil Mass [Kg]: 15.000
Oil type: mineral blended


Selective depolarization treatment (Chedcos) in order to remove the DBDS + dehalogenation treatment (CDP Process) in orderr to remove the PCBs both from oil and transformers. The treatments were performed on-site, on-line and on-load (transformer in servise and under charge during the treatment).

The treatments were carried out with the following guarantees: DBDS < 10 mg/kg, PCBs < 2 mg/Kg restoring also the other oil parameters as suggested by IEC 60422 ed. 4, 2013

Before the treatments

After the treatments

PCBs [mg/Kg]290,37
DBDS [mg/Kg]18< 5
IFT [mN/m]2442
CCD TestcorrosiveNOT corrosive
TAN [mg KOH/g]0,340,01
Dehalogenated and depolarizated transformers

Identified Critical issues

Applied solutions

Contact us to learn more about your case

I read the privacy information and authorize the use of my personal data for the purposes specified therein.
Insert this code: captcha