Oil water separators operate using various strategies which include gravitational separation or coalescence to separate oils and suspended solids from wastewater. The procedure involves wastewater entering into the separator where it is allowed to settle for some time during which its flow is slowed down. It is at this time that lighter oil being less dense as compared to water floats on top thus creating a clear layer of oil. This layer can be simply sloughed off, while the remaining water becomes clarified with respect to ecological requirements.
https://dustyfilters.com/