Following a similar order from DFDS earlier in 2013, a repeat order for PureSOX was placed by Dutch ship owner Spliethoff near the end of the year. The order confirms not only the commercial viability of the exhaust gas cleaning system, but also customer confidence in the system’s performance within Emission Control Areas (ECAs).
SOx Emission Control Areas (SECAs)
Signed in November, the order from Spliethoff comprises PureSOX systems for five Con-Ro vessels. The vessels will be retrofitted between June and December of 2014 reports the company.
PureSOX is a hybrid scrubber system, able to operate with either seawater or fresh water. And while the technology is relatively new, it has been demonstrated to reduce sulphur content in vessel exhaust by more than 98%.
An order based on real-world experience
Spliethoff, one of the largest ship owners in the Netherlands, has been operating with PureSOX aboard the M/V Plyca. Alfa Laval delivered the system in 2012, and it has been in continuous use aboard the vessel ever since it was installed. Sailing within the North European ECA, the M/V Plyca has logged more than 6000 hours in full compliance with the new IMO regulations.
Cleaning exhaust from multiple engines
The PureSOX system installed aboard the M/V Plyca is a multiple-inlet system, able to clean the exhaust gas from both the main and auxiliary engines. The same will be true for the deliveries in the new order. Each will serve four Wärtsilä engines with a combined power of 28 MW, handling an exhaust gas mass flow of 132,000 kg/h.
Spliethoff’s experience with the multiple-inlet installation aboard the M/V Plyca is that it is both efficient and reliable. According to Alfa Laval this can be expected no matter how many of the inlets are used at a given time. “With PureSOX, we’ve established very effective means of closing off the pathways from engines that aren’t in use,” the company says.
MV Plyca with Alfa lavals PureSOx Scrubber
Centrifugal separation – a key to success
Another area where PureSOX has proven effective is the cleaning of the scrubber wash water. PureSOX saves on caustic soda and fresh water by operating in an open loop with seawater. But in low-alkalinity waters or in harbours and other areas where discharge is strictly regulated, a closed loop with fresh water is an alternative. The fresh water in a closed loop must be cleaned, which has proven an Achilles heel for many exhaust gas cleaning systems. The roll and pitch of rough seas, for example, can make it difficult for filtering, settling or flocculation processes to manage their job. In PureSOX, however, Alfa Laval’s expertise in high-speed centrifugal separation has provided an answer.
Alfa Lavals PureSOX Scrubber, very effectic and easy to be retroffited
images source: Alfa Laval