Wartsila has announced that its Aquarius EC ballast water management system (BWMS) has been granted basic approval by the International Maritime Organization’s (IMO) Marine Environment Protection Committee (MEPC) during its 64th session in London, which commenced on Oct. 1, 2012.

According to Dr. Joe Thomas, director, ballast water systems, Wartsila Environmental Solutions, gaining IMO basic approvall is the first step towards full IMO type approval, and focuses on the fundamentals of the technology, including toxicity and environmental impact. The next stage, IMO final approval, examines full scale prototype test data and requires supporting documentation on aspects such as risk and safety to the ship, crew, general public and the environment.

Wartsila said that application for IMO final approval was submitted to the IMO immediately following the endorsement.  A key element of the submission was an investigation on the impact of the treated ballast water on uncoated and coated materials typically used in marine and offshore construction. Approval is expected at MEPC-65 in 2013.

Aquarius EC is a modular ballast water management system, providing what Wartsila said is a safe, flexible and economical process for the treatment of ballast water, achieved through a simple and efficient two stage process. Upon uptake the sea water is first passed through a back washing filter (first stage) and then the filtered sea water passes through a static mixer, where the disinfectant generated from the side stream electrolysis unit (second stage) is injected to ensure a maximum level of 10ppm in the treated ballast water.

During discharge the filter is bypassed and residual concentration of oxidants (TRO) in treated ballast water is monitored before being discharged overboard. If required, treated ballast water is neutralized by injecting sodium bisulfite into the main ballast line during discharge. Neutralization effectiveness is continuously monitored to ensure compliance with MARPOL discharge limits.