Pollution prevention is a top concern today, as the green revolution is not just about saving energy. Earth, air, water and other resources must remain sufficiently unpolluted to sustain life first. The role of oil water separators (OWS) is crucial in preventing water pollution from gas stations, auto repair shops, car washes, drill sites, and major oil/gas storage units. In this post, we will take a closer look at what these separators do and why their action is so important for the environment.
Oil Water Separators Keep Local Waterways from Becoming Polluted
Run-off, dirty water from a local gas station or a power wash will often mix with the local waterways. Over time, the pollution will make all nearby natural water sources unusable, killing fish, plants, animals, and devastating the local ecosystem. This has happened previously, and it still continues to happen in many parts of the world.
The usage of high quality oil water separators at the right locations can prevent this from happening. The ideal locations for maximizing the OWS systems are always at the end of a refuse pipeline and right at the point where the runoff is released into the sewer or a local water body. Next, we will look at how the different OWS systems work to achieve then necessary separation and filtration.
Parallel Plate Gravity Separators
The oily water waste is passed between two grooved plates with an oleophilic coating on each of them. The plates must be exactly parallel to each other, and the distance between them should not be any less than 6mm, or any more than 12mm. The two plates continue to collect the residual sludge, until the bubbles grow large enough to float up top, only to be scudded away until nothing else is left in the water to rise up anymore.
Hydrocyclone Water Oil Separators
The refuse water filled with residual hydrocarbons is injected or poured at an angle, right into the separator tank at high speed. The resulting centrifugal force creates the whirlpool necessary to forcibly expel only water from the tank, while the oil remains enclosed into the hydro-cyclone, close to the tank’s center. This is a powerful system, quite similar to actual underwater cyclones. These are reserved only for drill sites or large water treatment facilities.
Dissolved Air Floatation Separators
DAF separators infuse air saturated water into the refuse oil-water mix, forcing all the oily residues to rise up top at great speed, along with the numerous air bubbles. Sludge and debris which will not rise at this point will instead sink to the bottom. The residues up top are scudded off, and the oil-free water is pushed into the next chamber.
Classic Gravity Separators
Finally, we have the classic gravity-based oil water separators which use the same exact method to separate oil from water as the DAF separator already detailed above, but without the air-saturated water infusion. This makes it an outdated system today, since it exclusively relies on gravity to get the job done.
They all serve the same purpose of separating oil, grease, and leftover hydrocarbons from water, but the difference is in how these four primary separators do it. The classic gravity separator alone might not be enough on its own anymore though.