The cable oil purification process typically involves the following steps:

Heating: Oil is heated to reduce viscosity, enhancing the efficiency of subsequent processes.
Pre-Filtration: Removal of large particles using coarse filters.
Vacuum Dehydration: Eliminates moisture and dissolved gases under vacuum conditions.
Fine Filtration: Removes smaller particulates with fine filters, often down to micron levels.
Degassing: Further extraction of gases that may affect dielectric properties.
Adsorption Treatment: Uses materials like activated alumina to remove acids and polar contaminants.
Cooling: Oil is cooled to appropriate temperatures before returning to the cable system.
Monitoring and Testing: Continuous monitoring of parameters like moisture content and dielectric strength to ensure purification effectiveness.
These steps collectively restore the oil’s insulating and cooling properties, ensuring optimal performance of power cables.