PureSOx has been operating at sea since 2009. 50 systems have been ordered on 45 vessels.
The new PureSOX 2.0 is smaller and more flexible, says the manufacturer. The most evident difference in the updated model is the diameter of the absorber, which forms the bulk of the scrubber body. This has been reduced by around 15%, which lessens the likelihood that cargo or passenger space will be affected by the scrubber installation.
Further reduced is the size of the control system, which is half that of the earlier version.
The water cleaning unit is more modular in PureSOx 2.0, with equipment now distributed across three skids which can be loaded onto a ship separately and independently placed.
‘Size and flexibility are of primary importance when integrating a scrubber into a vessel, says Rene Dix, Alfa Laval manager, marketing and sales, exhaust gas cleaning.
The scrubber itself attenuates noise in PureSOx 2.0 resulting in it now being able to be positioned before the silencer, rather than after as previously required. Especially in a newbuild, this means it can be placed lower in the vessel. Not only does this improve vessel stability, it also has the benefit of reducing back pressure. ‘Lowering the pressure will ease the burden on the engine,’ Diks says, ‘which may have a positive effect on the vessel’s fuel consumption.’
Operationally the most notable difference in PureSOx 2.0 is the option of powder dosing, which applies to both closed-loop and hybrid configurations. When running in closed-loop mode, the circulation water must be dosed with an alkaline additive. Up to now this has always been the liquid additive caustic soda, but in PureSOx 2.0 a powder like sodium bicarbonate can be used instead. Taken aboard dry and loaded into a silo, the powder is mixed with desalinated water before entering the closed-loop circuit.
‘For the crew there is an immediate benefit in powder dosing, since it reduces the risks involved when handling the consumables,’ Diks says.
‘The long-term advantage is the fact that powder additives are less expensive. When powder dosing is chosen, there is a reduction in operating costs that offsets the equipment investment.’
Diks sees the new version as part of a total effort in emission control, which includes the new Alfa Laval Test & Training Centre in Aalborg, Denmark. Equivalent to a full-sized engine room on land – complete with all major process lines – this facility provides opportunities to further refine PureSOx and explore its interaction with other technologies on board.