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MCA approves Coldharbour BWMS

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LNG Industry,

Coldharbour Marine’s ballast water management system (BWMS), optimised for tankers and very large crude carriers (VLCCs), has recently been formally approved by the UK’s Marine and Coast Guard Agency (MCA) under IMO resolution MEPC 174 (58).  

Coldharbour believes its innovative ‘in tank-in voyage’ approach offers significant benefits for operators of large tankers, LNG carriers and large crude carriers, which typically carry thousands of tons of ballast water that cannot readily be treated by a two step BWMS relying on filtration followed by electro-chlorination or UV disinfection.

Coldharbour’s BWMS has no filtration and no connection to the ballast pumps or ballast lines. It is therefore immune to pump flow rates, pressure losses, power shortages and guarantees zero disruption during cargo and ballast operations,  including gravity ballasting and deballasting. Furthermore, by treating ballast water during the voyage, which can be up to 30 days for tanker operators, the risk of regrowth on is eliminated.

In 2012, the Coldharbour GLDTM technology was the first ballast water treatment system (BWTS) to be retrofitted to a 309 000 dwt VLCC and it was on this vessel that the first ship testing was completed in 2014 under the guidance of Lloyds Register. As a British company, Coldharbour was keen that the UK MCA, which used Lloyds Register to independently audit both the land and sea the results, accredit the system. 

Chief Executive, Andrew Marshall, explained said:  “We were keen that UK MCA undertook the Type Approval. UK MCA has a worldwide reputation for rigour; thoroughness and probity that will be welcomed by owners and operators who need to have confidence in their choice of BWTS. We are now looking at USCG AMS approval and, because of the additional effort we invested in our UK MCA/IMO testing, we believe we are very well placed to move forward to full USCG Type Approval within a reasonable timeframe.”

Coldharbour’s GLD™BWMS is a space saving, in-tank solution. A Coldharbour Inert Gas Generator (IGG) is linked to GLD™ units mounted inside each ballast tank. The GLDTM uses natural fluid dynamics to stir the ballast water, ensuring thorough treatment. Inert gas from the IGG reduces the ballast water oxygen content while its elevated CO2 level lowers the ballast water pH. As gas is introduced to the GLDTM  it is made to generate an ultrasonic frequency that physically disrupts the cell walls of aquatic organisms while gas micro-bubbles amplify the ultrasonic effects. Thus organisms are killed in three ways: by hypoxia, caused by low levels of O2; by hypercapnia, caused by the low pH/dissolved CO2; and by ultrasonic cell wall disruption.

Adapted from press release by

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