How to remove water after hydraulic oil enters water?

The dehydration treatment of hydraulic oil after water intrusion needs to adopt a step-by-step solution according to the degree of water intrusion. The following is a professional-level treatment process:

Emergency treatment (a small amount of water intrusion, water content <0.1%)

1. Standing stratification method

- Let the oil tank stand for more than 48 hours

- Slowly discharge free water at the drain valve at the bottom of the oil tank

- Applicable conditions: Only separate free water, cannot treat emulsified water

2. Heating sedimentation method

- Control the oil temperature at 60-65℃ (not exceeding the flash point of the oil -20℃)

- Keep the constant temperature for 4 hours and then cool naturally

- Combined with centrifugal separation, more than 80% of free water can be removed

Professional dehydration treatment (water content 0.1%-1%)

1. Vacuum dehydration technology

- Use a three-stage vacuum oil filter:

Technical parameters

Stage 1: -0.085MPa, remove large water droplets

Stage 2: -0.095MPa, remove tiny water droplets

The third stage: -0.099MPa, remove dissolved water

- Oil temperature control:

- Mineral oil: 60±5℃

- Synthetic ester oil: 50±5℃

- Treatment effect: Water content can be reduced to below 50 ppm

2. Coalescing separation technology

- Treatment process:

Emulsified oil → Coalescer (emulsification) → Separator (drainage) → Precision filtration

- Key parameters:

- Coalescing filter element accuracy: 1-3μm

- Separation efficiency: ＞95%

- Treatment speed: 0.5-2 tons/hour

Deep treatment (severe water inflow, water content＞1%)

1. Molecular sieve adsorption

- ｓｅｌｅｃｔ 3A type molecular sieve (pore size 3Å)

- Adsorbent addition: 3-5% of oil weight

- Treatment time: 6-8 hours of cycle treatment

2. Thin film evaporation technology

- Working conditions:

- Temperature: 80-100℃

- Vacuum degree: -0.098MPa

- Free water, dissolved water and emulsified water can be completely removed

Treatment effect verification

1. Testing standard

- Karl Fischer method (ASTM D6304): Water ≤100ppm

- Visual inspection: Oil is transparent and has no turbidity

- Demulsification test (ASTM D1401): ≤30 minutes

2. Oil recovery

- Supplement anti-emulsification additives (such as T1001)

- Addition amount: 0.1-0.3%

- Balance treatment: 24 hours of circulation filtration

Precautions

1. Safety regulations:

- Vacuum equipment must be reliably grounded

- Oil temperature must not exceed 80% of the flash point during heating

- The treatment area is equipped with explosion-proof ventilation

2. Economic judgment:

- When the treatment cost is ＞60% of the new oil price, it is recommended to change the oil

- The additive content of oil that has been infiltrated with water many times should be tested

3. System maintenance:

- All filters need to be replaced after treatment

- Check seals (water ingress can easily cause seal expansion)

- Check bearing lubrication of hydraulic pumps

Hydraulic oil treated by the above method can achieve:

- Water content: ≤100ppm (ISO 4406)

- Cleanliness level: NAS 1638 level 7

- The demulsibility is restored to more than 90% of the new oil standard

Note: For water ingress into synthetic hydraulic oils such as phosphate esters, special treatment equipment (such as low-temperature vacuum systems) is required, and ordinary molecular sieves are prohibited.