Erma First acquires Glosten subsidiary, 'world's smallest BWTS'

"[OneTank] delivers a quick to install additional solution for small ballast tanks on big ships as well as a stand-alone solution for small vessels... To win the battle against invasive marine species and effectively protect our vulnerable marine eco-systems, ballast water from internationally trading smaller vessels also needs treating in a way which is practical and economically viable. We believe we have this solution in the form of oneTank, a product which keeps it simple,” Erma First managing director Konstantinos Stampedakis said.

Most of the ballast water on tankers is in the gas hazardous cargo body ballast water tanks. This requires a high-capacity ballast water treatment systems (BWTS) approved for those hazardous gases. In addition, tankers have a relatively small volume aft-peak ballast water tank in a safe area. By regulation, the aft-peak ballast water cannot mix with the gas hazardous cargo body ballast water.

In the case of bulkers, since the aft-peak tank is located far away from the cargo body, it is usually serviced by a separate piping system, requiring a flow rate that is typically one-tenth of the cargo body.

OneTank treats ballast water within the vessel’s ballast tank and has no filters, ultra-violet lamps or electrolytic chlorine generators. Its footprint is only 600 mm x 600 mm, and its power consumption is similar to that of a household washing machine.

The system uses an 8.25% or 12.5% sodium hypochlorite (bleach) and 30% sodium thiosulfate solution – for smaller vessels, a 20-litre container of 12.5% bleach will treat approximately 288 m³ of ballast water. For larger vessels, oneTank can treat tanks as large as 4,000 m³.

Seawater is treated by applying and mixing the bulk chemicals in-tank.