For ship owners and operators preparing for the IMO’s 2020 global sulphur cap, there are numerous options open in order to reduce sulphur levels in their exhaust emissions.
Their ultimate ‘plan of action’ will be determined by the various pros and cons.
Retrofitting a scrubber, for example, requires a sizeable initial investment for equipment and installation – not forgetting the accompanying redesigning and reengineering scope. On the other hand, these ship owners will still be able to use HFO, which if the current state of affairs continues, is less expensive than low sulphur fuels.
“Payback times on scrubbers are getting much shorter with speculated price differences between HFO and compliant fuels, which makes the business case for scrubbers very compelling,” Erik Haveman, Alfa Laval sales director – exhaust gas cleaning, said.
Using wet scrubber technology, Alfa Laval’s PureSOx scrubber has multiple operating arrangements, two scrubber designs and a range of compliance profiles.
“Compliance is always in focus, but customers have a broad spectrum of other requirements – those can go well beyond open-loop, closed-loop and hybrid arrangements, or the choice between U- and I-designs. Today we can match a vessel’s sailing profile by optimizing PureSOx for different compliance needs, and we offer many options to suit a vessel’s individual circumstances.”
The company puts its products through their paces at the Alfa Laval Test & Training Centre. In this controlled environment, extreme conditions can be recreated.
“This lets us innovate and meet design targets more quickly, but it also allows us to explore customer-specific challenges and inquiries. For example, we can look for the best way to cool a hot scrubber for start-up, or find ways to adapt the system for a particular engine type,” Haveman continues.
Forming a team
Other scrubber manufacturers are moving towards increased collaboration to strengthen their market position. An example is this is the joint venture between AEC Maritime and VDL.
“The biggest advantage of this new joint venture is that it offers customers one-stop shopping for the entire process from sale and engineering, through to production and installation of the scrubbers,” Kevin Kuijs, director of the VDL AEC Maritime joint venture, explained.
The cooperation is furthered by the involvement of Damen Green Solutions – part of Damen Shipyards Group – which will be responsible for the complete installation of the scrubbers.
Other options available
While the majority of major scrubber manufacturers call on so-called ‘wet scrubber’ technology, some companies use ‘dry scrubber’ methods to achieve the desired effect of making exhaust emissions cleaner. One of those companies is Konutherm. At the moment they working on a new type of dry scrubber.
“Dry scrubbers are a better way of cleaning up emissions,” Marco de Jonge, Konutherm managing director, said.
“We believe that the use of wet scrubbers is not the most efficient response to the emission problem, as energy consumption on board increases significantly. On the other hand, the environmental problem is shifted. What about scrubber waste water treatment or drainage?”
De Jonge thinks that the greater energy consumption and subsequent increase in CO2 emissions will lead to further problems when the IMO decides in the near future that each vessel has to decrease its CO2 output.
Together with its German business associate Torsten, Konutherm has developed dry scrubber technology in the form of its patented Regenerative High Temperature Absorber (RHTA).
“This dry scrubber removes SOx, NOx, VOCs, carbon black, dust and CO from the exhaust gases of the ship and has an integrated exhaust gas heater (economizer) for heat recovery to allow for economical HFO operation. Besides this, the RHTA operates as a silencer and has a low exhaust gas pressure drop,” De Jonge explained.
The company is looking for investors to bring this type of scrubber to the market.
EU Stage V
Of course, the IMO global sulphur cap is not the only emissions legislation facing the maritime industry. Looking specifically at the inland waterway sector, European NonRoad Mobile Machinery (NRMM) regulations also apply.
To this end, maritime exhaust specialist Discom has developed a post-treatment unit to allow new and existing Caterpillar 3512 engines to comply with NRMM Stage V emission standards. The project was developed in collaboration with Yerseke Engine Services and the system was built into the Vera Pax barge that VEKA is completing in Werkendam for Belgian inland waterway company Fabian De Wachter.
“This will be the first freight vessel in non-stop operation to meet the NRMM EU Stage V standards,” Werner van Well, Discom account manager, stressed.
Combining selective catalytic reduction equipment with a particulate filter, this post-treatment system can be used in both existing and new engines.
“It’s easy to use. The management system says when the filter needs replacing after about 10,000 hours of operation. It’s a question of unscrewing a few bolts. We conduct annual checks on board to make sure the system is working correctly and we assume the responsibility in that area. So we eliminate all the fuss and worries for inland waterway companies.”
This article was previously published in Maritime Holland edition #6 – 2017.