Insulating oil regeneration filter function introduction

Transformer Oil Regeneration Plant is a highly efficient equipment specially used for purifying, dehydrating, degassing, deacidifying and regenerating aged transformer oil (insulating oil). It can not only remove moisture, gas and mechanical impurities in the oil, but also deeply treat oxidation products (such as acid value, sludge, pigment, etc.), restore the electrical properties and chemical stability of the oil, and extend the service life of the transformer.

Main functions

| Function | Role |

|------------------------|------------------------------------------------------------------------------------------|

| Dehydration and degassing | Remove free water, dissolved water and gas (such as air) to improve insulation strength. |

| Mechanical impurity filtration | Remove particulate matter (metal chips, fibers, dust, etc.) to prevent equipment wear. |

| Deacidification | Reduce acid value (KOH) to prevent sludge generation and corrosion of insulating materials. |

| Adsorption regeneration | Remove colloid, pigment, oxidation products, and restore oil color and chemical stability. |

| Improve electrical performance | Increase breakdown voltage (≥60 kV) and reduce dielectric loss factor (tanδ). |

| Extend oil life | Reduce oil change frequency and maintenance costs. |

2. Applicable scenarios

- Aged transformer oil (high acid value, dark color, excessive dielectric loss).

- Damp or slightly contaminated insulating oil (excessive moisture and particulate matter).

- Pretreatment before maintenance or oil change to reduce new oil consumption.

- Daily maintenance of power systems, substations, and large transformers.

Core working principle

Insulating oil regeneration purifiers usually use "physical + chemical" combined treatment, and the main processes include:

1. Pretreatment (coarse filtration)

- Remove large particle impurities (≥50 μm) through metal mesh or filter element.

2. Heating (reducing viscosity)

- The oil temperature is controlled at 50-70℃ (avoid high temperature oxidation).

3. Vacuum dehydration and degassing

- Oil is atomized in a high vacuum (≤0.1 kPa) environment, and water and gas evaporate and are extracted.

4. Adsorption regeneration (key step)

- Oil passes through adsorbents (activated alumina, silica gel, clay, etc.) to remove acid, colloid, and pigment.

5. Precision filtration

- Use 1-5 μm filter elements to intercept residual particles to ensure the cleanliness of oil products.

6. Reuse after qualified testing

- Test indicators such as moisture, acid value, and breakdown voltage, and re-inject into the transformer after meeting the standards.

Differences from ordinary oil purifiers

| Comparison items | Ordinary oil purifier | Insulating oil regeneration oil purifier |

|------------------|-----------------------------|-----------------------------------|

| Main functions | Only filter impurities, dehydrate and degas | Filtration + dehydration + degassing + deacidification + adsorption regeneration |

| Processing capacity | Suitable for lightly contaminated oil | Can handle severely aged and acidified oil |

| Adsorption system | None | Equipped with adsorption tower (activated alumina/white clay) |

| Oil recovery | Cannot reduce acid value | Can reduce acid value to ≤0.05 mg KOH/g |

| Application scenarios | Daily maintenance | Regeneration of aged oil, overhaul and oil change pre-treatment |

Technical parameters (reference)

- Processing capacity: 1000~10000 L/h (customized according to needs).

- Working vacuum: ≤0.1 kPa (absolute pressure).

- Heating temperature: 50~70℃ (adjustable, anti-oxidation).

- Filtration accuracy: 1~10 μm (customizable).

- Oil quality standards after treatment:

- Breakdown voltage ≥60 kV (IEC 60156)

- Water content ≤10 ppm (ASTM D1533)

- Acid value ≤0.05 mg KOH/g (IEC 62021)

Advantages and characteristics

✅ Efficient regeneration: can deeply treat severely aged oil and reduce oil change costs.

✅ Fully automated: PLC control, real-time monitoring of temperature, vacuum, flow and other parameters.

✅ Energy saving and environmental protection: oil recycling, reducing waste oil emissions.

✅ Flexible mobility: optional vehicle-mounted or fixed, suitable for on-site operations.

Insulating oil regeneration purifier not only has the dehydration, degassing and filtering functions of ordinary oil purifiers, but also can reduce the acid value and remove oxidation products through adsorption regeneration, so that the aged oil can be restored to the standard close to the new oil standard. It is a key equipment for the power system to maintain the performance of transformer insulating oil.