What Is The Procedure Of Marine Oil Water Separators?

To operate a ship, bilges are a necessary evil. They usually contain a combination of water,

oils and physical impurities. though the build up of bilges can be minimized, it can never be

eliminated. In the good old days, the ship’s crew used to pump it overboard without a second

considered. As concerns about the environment and air pollution grew, the laws relating to

pumping bilge waters overboard have become very strict. Marpol regulations have become

stringent and it has become mandatory to have marine oil water separators on all types of

ships. Only treated water, containing less than 15 components per million of oil, can be

pumped overboard. As per Marpol regulations, in addition to installing an oily water

separator, it is also mandatory to have a PPM monitoring gadget which will sound an alert

when the PPM of oil exceeds 15.

The marine oil water separators consists of different stages. In the initial stage, the bilge

water is sent to the separation chamber through an inlet pipe. Some of the oil molecules, due

to their lower density, will separate from the combination and rise to the top of the chamber.

This oil is collected in an oil collection compartment. The balance bilge water is sent although

an outlet pipe at the bottom of the original stage and it enters the fine separating chamber,

which forms the next stage of the separation process. In the fine separating chamber, there

are stationary catch plates which are arranged in an equidistant, concentric stack in the

Middle of the chamber. This chamber is provided with vapor vents or heating coils to facilitate

the flow of oil. Any gases formed are vented from the top of the chamber. In this chamber,

the oil water mixture flows gradually among the catch plates. The oil will stick to the

underside of the capture plates and slowly move towards the outer part of the plates and

then rise to the top into the oil accumulating area. This chamber can be emptied when full.

From this chamber, the combination goes to the filtration unit.

The filtration in the marine oil water separator takes place in two stages. In the preliminary

stage, filter units get rid of the physical impurities. These settle at the bottom and can be

removed periodically. The filtering systems are cleaned every 15 days or more frequently if

necessary. The water then enters the coalescing chamber. Here there are ‘coalescer’ inserts

which break down the surface tension amongst the oil molecules. This induces the oil

molecules adhere collectively to form larger molecules. These rise to the upper portion of the

mixture and are collected in the collection chamber and can be emptied as needed. When

the water comes out of this stage, the PPM of oil will be less than 15. If it exceeds this limit,

then the alarm will sound. Jetvac Inc. is a Respected manufacturer of marine oil water

separators and they have many years of experience in this field. They have created robust,

but user friendly separators, which require minimal maintenance.