No effective BWMS without good filter systems

A crucial first step in UV and EC ballast water treatment is the filtration of all incoming seawater during uptake. We use a high quality 40 micron backflushing filter that offers an exceptional high and reliable performance. It allows for a very consistent second stage treatment of the ballast water to IMO and USCG standards. Our filter systems are designed by our trusted partner FilterSafe.
When up-taken seawater is not properly filtered, following expensive problems can occur:
  • Microorganisms make it through to the second stage, overwhelming the secondary treatment mechanism and allowing some organisms to make it out alive.
  • Built-up sediment in ballast tanks increases the ship's weight, hence the need for more fuel to sail. 
  • Low quality filters end up in a state of constant backflush, constantly trying to clean themselves in order to stay functional because of their incapability to process the water.
 
The patented nozzleX technology cleans 100% of the filter screen every time, without any wear on the nozzle or the screen
 

Benefits of our filter system

  • 40 micron filtration with a long screen life, thanks to duplex 904L construction made of the highest grade material available in the industry 
  • Continuous operation, even during backflush process
  • Minimum chance of operational issues and blinding thanks to sensibly and sustainably sized mesh velocity
  • Ability to recover from exceptionally high TSS situations with no operator intervention thanks to the right sizing
  • Guarantee of exceptionally high strength and long reliable service of the screen while allowing for easy inspection of the mesh during the lifetime of the equipment
  • Smooth screen design allowing for adequate handling of increase in differential pressure during high TSS events while recovering quickly
  • Low backflush flow rate requirements during self-cleaning process
  • Simple and easy maintenance
modular design filtration systems BWMS Wärtsilä

How filters work

Water starts its journey to the ballast tank by being pumped onboard. It may go immediately to the filter or have to travel a distance across the ship to get there. Once it arrives at the filter, it goes through a prefiltration section that removes large particles. The smaller particles then enter the filtration chamber where organisms and dirt are trapped by the screen. As more and more particles build up on the screen, a sensor recognizes a difference in the pressure of the water coming into the filter and going out of it. This triggers the automatic self-cleaning cycle, where the dirt on the screen is sucked up by the nozzles and is dumped overboard. The pressure returns to normal and the filtration continues. At this point the water is ready to go to the secondary treatment stage to be neutralized before filling the ballast tanks.

Sometimes the water is filtered and treated after it has already been in the tanks, before being pumped overboard.

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