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oil separator for bilge water

There is no actual oil leak into the bilge but when pumping out bilge water there is often a film of oil from the discharge. Are there any separators that can easily be installed in the bilge pump outlet?

Asked by: Martin Brett  | 12.48pm, Tuesday 22 November

WW says:

It is indeed true that a tiny trace of oil in bilge water can produce a terrible looking oily film when pumped out into the canal. There are filters that can be fitted between a bilge pump and the outlet which will solve your problem. Vetus and BilgeClear both offer filters which will suffice. If the bilge pump is fitted in an oil tight area or engine drip tray the filter must be capable of 5ppm discharge performance to meet the BSS requirement.
Bilge water does tend to be dirty with particulate matter which will tend to clog a filter quite quickly, so a simple particle filter on the pump intake might prolong filter element life.

Rupert Smedley  | 3.44PM, Tuesday 22 November

You may also find that an oil absorption mat in the bilge can help soak up excess oils before they are pumped overboard- this is common practice now on larger commercial vessels. The materials only soak up hydrocarbons (such as diesel and lubricating oil, and sterngland grease- a common cause of oil contamination in bilge water). Once used, they are disposed of ashore in oil-contaminated waste (usually at a garage or a council-run waste disposal site- as you would used oil filters)).
The mats are very useful, and can be also installed in the engine drop tray to help absorb any drips- and can usefully help identify the position of any minor leaks.

Mark Langley  | 11.11AM, Wednesday 23 November

I should add, that the mats/booms work very well when combined with a bilge pump line filter.
As Rupert points out, a pre filter (such as some coarse plastic meshing around the bilge pump intake) can reduce the load passing through the filter.

Mark Langley  | 11.12AM, Wednesday 23 November

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