How to separate oil and water with an oil purifier?

Use an oil purifier (oil-water separator) to separate oil and water, usually by centrifugal separation, gravity sedimentation, filtration, or coalescence separation. The following are the specific steps:

1. Choose the right type of oil purifier

Common oil-water separation equipment includes:

- Centrifugal oil purifier (high-speed rotation to separate oil, water, and impurities)

- Gravity sedimentation separator (natural stratification using density difference)

- Coalescing separator (using special filter materials to aggregate tiny oil droplets into large oil droplets)

- Vacuum dehydrator (suitable for high-precision dehydration, such as lubricating oil and transformer oil)

2. Operation steps (taking the centrifugal oil purifier as an example)

(1) Pretreatment

- If the oil contains a large amount of solid impurities (such as metal chips and sludge), first remove them through a filter or sedimentation tank.

- Heating (optional): If the oil has high viscosity (such as waste oil), it can be heated to 50~70℃ to reduce the viscosity and improve separation efficiency.

(2) Start the oil purifier

- Check whether the equipment is intact and ensure that the motor, drum and other components are normal.

- Start the machine and wait until the speed reaches a stable state (centrifuges usually require several thousand to tens of thousands of revolutions per minute).

(3) Oil inlet separation

- Slowly pump the oil-water mixture to be treated into the oil purifier to avoid excessive flow affecting the separation effect.

- Under the action of centrifugal force:

- Water (high density) is thrown to the outer layer and discharged through the drain.

- Oil (low density) gathers in the inner layer and is recovered from the oil outlet.

- Solid impurities are deposited on the drum wall and need to be cleaned regularly.

(4) Monitoring and adjustment

- Observe the liquid state of the water outlet and oil outlet, and adjust the oil inlet speed or centrifuge speed to optimize the separation effect.

- Use a moisture detector (such as a Karl Fischer moisture meter) to check the water content of the treated oil to ensure that it meets the standard (for example, industrial oil requires a moisture content of <0.1%).

(5) Shutdown and maintenance

- After separation is completed, stop the oil supply first, then turn off the power.

- Clean the residue in the drum to prevent clogging or corrosion of the equipment.

3. Other separation methods

- Gravity sedimentation method: Let the oil-water mixture stand, and the oil floats on the upper layer and is manually extracted (suitable for small amounts of oil-water separation).

- Coagulation separation method: The oil passes through the oleophilic and hydrophobic filter material, and small oil droplets gather into large oil droplets and then float up and separate.

- Vacuum dehydration method: Heat the oil under negative pressure, and the water evaporates and is extracted (suitable for precision dehydration of insulating oil, etc.).

4. Precautions

- Safety first: Prevent scalding when handling high-temperature oil, and electrical equipment must be grounded and explosion-proof.

- Environmental protection requirements: The separated wastewater must be treated to meet the standards before discharge (such as oily wastewater must be treated by biochemical or adsorption).

- Equipment maintenance: Regularly ｒｅｐｌａｃｅ the filter element and clean the drum to avoid efficiency loss.