Nameplate data of transformer:

Transformer: grid transformer
Manufact: xxx
Year: 1957
Power [MVA]: 50
Voltage [KV]: 225
Oil Mass [Kg]: 38.000
Oil type: blended mineral oil

Transformer contaminated by PCBs and corrosive sulfur compounds


Selective depolarization treatment (Chedcos) in order to remove corrosive sulfur compounds and dehalogenation treatment (CDP Process®) in order to remove the PCBs from oil and transformer. The treatment was performerd on-site and on-load (transformer in operation and fully load during the treatment).

Before the treatments

After the treatments Sea Marconi

PCB* [mg/Kg]8120
Total sulfur [mg/Kg]21,60020,500
TCS (total corrosive sulfur)
as DBDS Eq. [mg/Kg]
140< 10
CCDCorrosiveNOT Corrosive
DBTP [mg/Kg]380280
TAN [mg KOH/g]0,096< 0,03

*The agreed guarantee was PCBs < 40 [mg/Kg]

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