How Oil Skimmers Work

How Oil Skimmers Work

The working principle of all types of oil skimmers is based on the same fundamental concepts—only the implementation differs.

All oil skimmers take advantage of oil’s higher viscosity to enable separation. Since oil adheres to foreign objects longer than water does, skimmers typically use structures to which the oil can stick. These structures can be belts, discs, tubes, or similar components, leading to different types of oil skimmers.

Essentially, the skimmer provides a surface where oil can accumulate. This surface moves continuously so that the oil is carried away from the water’s surface and scraped off into a collection container.

The key requirement for this process is that oil separates from water and floats on its surface, which occurs due to the difference in density between water and oil.

Types of Oil Skimmers:

• Belt skimmers
• Disc skimmers
• Tube skimmers
• Belt-type skimmers

Why Oil Might Not Separate from Water

In some cases, oil may not separate properly from water or other liquids. This can be due to several factors:

1. Chemical additives (emulsifiers) binding oil to water
2. Turbulent liquid conditions preventing oil from settling
3. Oil droplets too small to float to the surface

Solutions for Oil Separation Problems

2. The Liquid is Too Turbulent

If strong turbulence prevents oil from rising to the surface, the solution is to reduce movement so the oil can settle.

• If possible, turning off the system for a while may help.
• If continuous operation is required (e.g., in three-shift production), a portion of the liquid must be pumped into a separate tank where it can settle. This is where oil separators come into play, as they are designed for precisely this purpose.

3. Oil Droplets Are Too Small

If oil droplets are too tiny, their buoyancy force may not be strong enough to overcome the water’s internal resistance and rise to the surface.

• The solution is to merge small droplets into larger ones, a process known as coalescence.
• Coalescence is the act of merging smaller entities into a larger one. In this case, small oil droplets stick to a special surface, where they gradually combine into larger droplets.
• Once the droplets are large enough, they naturally rise to the surface. This process is facilitated by oil separators, also known as coalescence separators.