Coalescing Separation

Sometimes the surface tension between oil and water increases to a point where neither gravity nor centrifugal force is sufficient to remove the water from the oil. In this situation, a coalescence separation system might be employed. Coalescence involves forcing the water and oil through a screen-like feature of the system. The oil is able to pass through the screen; the water cannot pass through, collects, flows down by gravity, and is then drained from the system. As in a centrifugal system, the oil remains in motion. Also on the positive side, turbine does not have to be shut down or be fitted with a settling reservoir. A coalescence system may not require that the oil be out of service. Like centrifugal separators, coalescence separators use energy inputs to remove the water.