In an impingement style oil separator, what is the first step of separation?

In an impingement style oil separator, the first step of separation is impingement. This process involves forcing the contaminated fluid to collide with a surface or barrier, which causes larger particles, such as oil droplets, to separate from the water phase due to momentum transfer. During this collision, the oil droplets are effectively removed from the main flow, allowing them to coalesce and rise more easily in subsequent separation stages. This impingement action is critical as it initiates the separation process by segregating the contaminants from the cleaner fluid, setting the stage for more refined separation techniques to follow.

Gravity, change of direction, and coalescing filters are later stages in the separation process that assist in further refining the separation of oil from water. Gravity relies on the different densities of the substances to allow the lighter oil to rise above the denser water, while change of direction involves altering the flow path to enhance separation efficiency. Coalescing filters are utilized later to gather smaller oil droplets into larger ones, facilitating easier removal. Each of these steps builds upon the foundational action established by the initial impingement.