Recognizing that no one solution is suitable across all ship types Wärtsilä Water Systems designed two technology choices for Ballast Water Management: AQUARIUS® UV and AQUARIUS® EC. Wärtsilä AQUARIUS® UV is suitable for vessels with small to medium pump capacities. Whereas Wärtsilä AQUARIUS® EC is better suited for vessels with larger pump capacities.
The AQUARIUS® UV system is a two stage approach with filtration followed by disinfection using ultraviolet light. Upon uptake, seawater is first passed through an automatic backwashing filter (1st stage). The filtered seawater then passes through a UV chamber (2nd stage) where ultra-violet light is used to disinfect the water before entering the ballast tank. On discharge, water from the ballast tank is pumped through the UV chamber for a second time to complete the disinfection process prior to discharge. The filter is not used during discharge. Wärtsilä AQUARIUS® UV IMO Type Approval was awarded by the Netherlands administration during December 2012, and was followed by USCG Alternate Management System (AMS) in October 2013.
The AQUARIUS® EC system is a two stage approach with filtration and electro-chlorination. Upon uptake the sea water is first passed through a automatic backwashing filter (1st stage), and then filtered water passes through a static mixer, where disinfectant generated from the side stream EC Cell Module (2nd stage) is injected to ensure a maximum dose of 10ppm in the treated ballast water prior to entering the ballast tank. At discharge, water from the ballast tanks by-passes the filter and residual concentration of disinfectant is monitored. If required, treated ballast water is neutralized, ensuring compliance with MARPOL discharge limits.
Wärtsilä AQUARIUS® EC IMO Type Approval was awarded by the Netherlands administration during December 2013.
The modular approach provides maximum flexibility during system design and installation where key components are positioned to suit available space, a major advantage when considering retrofit projects. Retrofit installations can be carried out either during dry docking, at the quayside or whilst the ship is in operation, thus minimizing any impact on ship downtime.