Biological Separator

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In the first stage, contaminated bilge water is pumped directly into the system. This stage separates oil from water and allows sludge/suspended solids to collect in the bottom of Stage 1. In this stage, there is an oil probe that allows pure oil to pass through a solenoid operated valve into any waste oil tank. The remaining oily mixture is continuously pumped into the second stage.

In the second stage, oily water passes through a support medium to which hydrocarbon-degrading bacteria are attached. The bacteria secrete a biological "glue" (polysaccharide), which tightly binds them to the support medium. This strong binding minimizes bacterial washout due to the flow of water through the system or the motion of the ship. The oil and related contaminants are degraded in this biological layer as the bacteria actually "consume" the hydrocarbons. The naturally-occurring bacteria used in the system are safe and non-pathogenic: "trained" to live in an environment just like bilge water. Detergents and other emulsifiers actually help this process because they break the oil into "bite size pieces" for the bacteria.

The third stage allows for any remaining solid particles to be removed prior to pumping the clean effluent over the side.