Scenario
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
Solution
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] | 81 | 20 |
| Total sulfur [mg/Kg] | 21,600 | 20,500 |
| TCS (total corrosive sulfur) as DBDS Eq. [mg/Kg] |
140 | < 10 |
| CCD | Corrosive | NOT Corrosive |
| DBTP [mg/Kg] | 380 | 280 |
| TAN [mg KOH/g] | 0,096 | < 0,03 |
| IFT | 19,5 | 26 |
| Color | 6,9 | 3 |
*The agreed guarantee was PCBs < 40 [mg/Kg]
