Everything You Need To Know About Working of An Oil/Water Separator


If you’re an industry owner and think oil mixing with water won’t affect your facility’s operations, you may want to think again.

The truth is, different industrial methods like food processing, machining, facility washdown, tank truck wash, manufacturing, power generation, etc., can lead to mixing oil and water. 

The oil needs to be segregated before the water is released to the water treatment plants or reused again. 

Industries are always looking for effective and efficient ways to segregate oil from water in their routine operations. The ideal oil separator configuration can protect the environment, enhance the overall methods, reduce costs, avoid fines, and generate the desired income.

So, if your industrial facility contains oily water, this article is for you. Continue reading to find out why a good oil-water separator can benefit your facility. 

Oil/Water Separator – What is It?

An oil-water separator allows wastewater to be safely discharged into a designated point of release, such as a drain. It eliminates oil, grease, and hydrocarbons while leaving behind non-hazardous water. The wastewater can then safely be disposed of in drainage.

Most refineries and several facilities have installed oil-water separators to aid their operations better. This includes industries ranging from steel mills to railroads.

Operating an Oil-water Separator

Oil/water separators are usually installed for difficult applications around the world. Being flow-through devices, they segregate oils from stormwater, industrial wastewater, and process water. 

Oil and water will get separated under specific cases due to the differences in specific gravity. Stoke’s Law is a formula that defines how quickly an oil droplet rises or settles. 

It defines the rate at which oil separates from lighter liquids. This is based on certain factors, like:

  • Collection tank’s size
  • Size and density of the oil drop
  • The flow rate
  • Distance traveled by the object. 

Different Types of Oil Water Separators

Coalescing Oil-Water Separators

Coalescing separators are similar to gravity separators because the usual water and oil flow are the same in oil separators. 

Oil and water can flow through oleophilic media in a coalescing separator. This allows oil drops to adhere to the media’s surface. The oil drops that coalesce or bind together gain size and become buoyant. This allows them to rise faster and accelerate the separation process.

API (Gravity) Separators 

This industrial oil-water separator is based on the difference in gravity and specific gravities of oil. Here is how it works:

  • The separator’s inlet receives oily water. 
  • The baffles reduce the turbulence of the water. This makes most of the solids in the water settle at the separator’s bottom. 
  • The second baffle inhibits the oil drops from exiting the separator. These drops have already come to the top of the surface and are collected at the exit. 

Why Should You Consider An Oil-Water Separator?

Facilities with oily wastewater or process water can efficiently use an oil-water separator to separate oil from the water. The water is then reused or discharged back into the environment. You can expect the following benefits from the right separator design that is tailored to your specific application.

  • Improved Oil Removal: An oil skimmer can remove oil more efficiently when oily water has been given enough time and space. The oil will separate into two layers.
  • Improved Wastewater Treatment: Separating oil from the wastewater before chemical treatment or filtration makes treatment more efficient, and equipment lasts longer.
  • Environmental Compliance: Oil-water separators lead to cleaner wastewater that meets all requirements of federal and local regulations.
  • Low Maintenance: The right oil-water separator tank will be specified to meet the requirements of the application. This allows for efficient oil separation and removal. It also means that less maintenance is needed so that downstream treatment equipment will work more efficiently.
  • Potential revenue generator: You can sell the separated oil as a valuable commodity in certain cases.

Final Word

An oil-water separator is an excellent setup to segregate oil from water in large volumes. However, as a facility owner, you’d know there are several oil spillages in an industrial facility that require expert attention. 

Guess what – professional oil spill clean-up companies can do the job for you. They’re experts in what they do, and you can focus on other important operations.

We’re sure this article was a complete bang for your buck!