What are the transformer oil treatment equipment?

Transformer oil treatment equipment can be divided into the following categories according to different purification goals (such as dehydration, degassing, impurity removal, regeneration, etc.). Each equipment has its focus on the pollution type and working principle:

Common equipment classified by function

1. Physical purification equipment

- Centrifuge

- Function: Remove mechanical impurities such as free water, metal particles, fibers, etc.

- Applicable scenarios: Oil with high water content (>1000ppm) or a large amount of solid pollution.

- Representative equipment: Disc centrifuge (such as Alfa Laval's BTPX series).

- Plate and frame pressure oil filter

- Function: Intercept particulate matter through filter paper/filter membrane (accuracy 1~5μm).

- Features: Simple structure, but frequent replacement of filter materials is required, suitable for small-scale treatment.

- Vacuum oil filter

- Function: Heat the oil in a vacuum environment, evaporate water and remove dissolved gases.

- Key parameters: vacuum degree ≤50Pa, temperature 60~65℃.

- Advantages: can handle dissolved water (down to below 10ppm) and trace gases.

2. Chemical regeneration equipment

- Adsorption tower system

- Function: remove acidic substances and colloids through adsorbents such as silica gel and activated alumina.

- Regeneration ability: can reduce acid value (to <0.03mg KOH/g).

- Typical equipment: molecular sieve adsorption regeneration device.

- White clay processor

- Function: add activated white clay to adsorb aging products and improve oil color and dielectric properties.

- Note: Subsequent fine filtration is required to remove white clay residues.

3. Deep processing equipment

- Electrostatic oil purifier

- Principle: Use a high-voltage electrostatic field to precipitate colloidal particles.

- Applicable: treat ultrafine particles (<0.1μm) and colloidal pollution.

- Membrane separation equipment

- Function: selectively separate dissolved water and small molecular pollutants.

- Technology: Reverse osmosis (RO) or nanofiltration (NF) membrane, with nanometer precision.

Composite integrated equipment

1. Multifunctional vacuum oil filter vehicles

- Functional integration: vacuum dehydration + precision filtration + degassing, such as GZJ series.

- Treatment indicators: breakdown voltage ≥ 70kV, moisture ≤ 5ppm.

- Application: on-site maintenance of substations.

2. Mobile oil regeneration workstation

- Process: centrifugal separation → heating vacuum dehydration → adsorption regeneration → polishing filtration.

- Case: Oil Purification Unit (OPU) of HITECH, Germany.

Auxiliary equipment

- Online monitoring system

- Sensor: real-time monitoring of moisture, particle size, and dielectric loss (such as a Vaisala humidity sensor).

- Heating system

- Type: electric heater, steam heat exchanger (control oil temperature at 50~70℃).

- Oil storage tank

- Design: Cone bottom structure with a drain valve to facilitate impurity sedimentation and separation.

Key points for equipment selection

| Type of pollution | Preferred equipment | Alternative solutions |

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

| Free water + large particles | Centrifuge | Plate and frame oil filter |

| Dissolved water + gas | Vacuum oil filter | Membrane separation equipment |

| Acidic substances/colloids | Adsorption regeneration device | White clay treatment machine |

| Comprehensive pollution (old oil) | Multifunctional vacuum oil filter vehicle + adsorption tower | Staged treatment |

Special scenario solutions

- Severe cold areas: Choose a vacuum oil filter with a low-temperature preheating function (such as Nordson's Cold Climate version).

- Flammable environment: Explosion-proof equipment (ATEX certified), such as Schneider's Ex series.

- Ultra-high voltage transformer: needs to be treated to moisture ≤ 3ppm, "centrifugal + vacuum + electrostatic" three-stage combination is recommended.

Economic efficiency and maintenance

- Cost comparison:

- Centrifugal separation: The equipment price is high (￥200,000~500,000), but the operating cost is low (￥0.5/L).

- Vacuum oil filter: The equipment price is medium (￥100,000~300,000), and the energy consumption is high (￥1.2/L).

- Maintenance cycle:

- Centrifuge bearing: Lubricate and ｒｅｐｌａｃｅ every 2,000 hours.

- Vacuum pump oil: ｒｅｐｌａｃｅ every 500 hours.

By combining the above equipment reasonably, the full process needs from daily maintenance to waste oil regeneration can be met. The specific plan needs to be customized according to the oil test report (such as GB/T 7595 standard). For large power companies, it is recommended to establish a centralized oil treatment center to improve efficiency.