Exhaust gas abatement technologies have reached a point of maturity where it is time to explore wider applications beyond sulphur compliance, says Kashif Javaid from technology group Wärtsilä. Scrubbers could filter NOx, black carbon, CO2 or even microplastics in the future
How has the scrubber business evolved sin[ds_preview]ce the entry into force of IMO 2020?
Kashif Javaid: Exhaust gas abatement technology has been a key enabler of complying with the IMO’s Sulphur Cap implemented from 2020. The years leading up to the ruling, notably 2018 and 2019, boomed with scrubber orders, and even throughout 2020 we saw strong demand for the technology. The business case for installing scrubbers has continued to grow, and there have been more enquiries for retrofits. Indeed, the fuel spread between HSFO and VLSFO bolsters scrubbers’ position as the current economics continue to favour them as the best compliance option for sulphur cap regulations.
We have also seen continued healthy interest in orders for scrubbers on the newbuild side, and some shipyards are promoting scrubber-equipped designs, as they modernise series designs to meet EEDI Phase 3 standards.
How have scrubbers evolved technically?
Javaid: We have pushed forward with technological developments, and last year we introduced the IQ Series Scrubber which takes up 25 % less space, is 30 % lighter, and has 35 % less volume than existing systems. This minimises the impact on a vessel’s cargo-carrying capacity, and therefore its profitability, making it particularly beneficial for container ships where space is a key commercial priority. The scrubber is also a more environmentally-friendly option for owners and operators looking at the impact of their investment decisions, as we are using 50 % recycled steel in scrubber manufacturing.
We believe exhaust gas abatement technologies have reached a point of maturity where it is only right that we explore their wider applications beyond sulphur compliance. The IQ Series Scrubber can be configured to use between 20 and 70 MW of power depending on vessel requirements, and features the same modular design as our other exhaust gas cleaning solutions. This means that all systems can be upgraded with further technologies that enable other pollutants to be tackled within the stack, including exhaust gas recirculation (EGR) to cut NOx, a black carbon filter to cut particulate matter (PM), a depluming unit to cut visible steam from the stack, and soon a carbon capture and storage (CCS) solution that we are currently developing in a test facility in Moss.
Another example of the wide perspective we take on sustainability is the development of a new patented system that uses scrubber washwater to filter microplastics from the world’s oceans. The system can capture particles smaller than 10 µm at a captured concentration of around 76 particles/m3. Adding an abatement solution for microplastics to our portfolio reinforces our commitment to make exhaust gas cleaning systems part of a modular platform that can enable further environmental technology innovations.
When will we see the commercialization of scrubbers with CCS-capabilities?
Javaid: The next few years will see a major transformation in the shipping industry. We recognised early on that CCS has the ability to reduce a significant amount of carbon emissions in a relatively short timeframe. We have already installed a 1 MW pilot plant at our test facility in Moss, Norway, to test our CCS technology in different conditions and identify the unique particularities of designing a system for ships. Initial results prove that this technology can meet our ambition of capturing 70 % of CO2 at the point of exhaust – a target chosen to be in line with IMO targets to reduce this same amount.
One of the next key steps for us is to conduct a pilot retrofit installation of our CCS technology on Solvang’s 20,000 tdw ethylene carrier ›Clipper Eos‹ by 2023. This pioneering project reinforces our strong position in the market, and we are already seeing strong interest from other owners.
Could CCS be a retrofit solution?
Javaid: We have conducted extensive research and development to explore how CCS can be developed and scaled in maritime. Initial findings show that CCS on existing ships is technically viable for the sector to pursue. This is exciting because carbon capture can provide significant CO2 reductions in a relatively short timeframe, and it will enable us to safeguard existing assets as we move to a cleaner mode of operating. There are already lots of vessels at sea – many at an early stage of their lifecycle – so it is important that the sector adjusts and finds solutions that work with the current fleet, rather than enact the carbon-intensive process of scrapping and building new ships.
To this effect, we are ensuring that CCS technologies are true lifecycle solutions that consider factors such as heat demand, power consumption, footprint, and size across the two to three decades a ship could reasonably be expected to operate for.
Would the storage tank size be significant for a CCS system?
Javaid: Following research into different solutions for developing CCS, we have found that a solvent-based CCS system will be most suitable in size and cost for commercial shipping. In terms of storage, we believe liquefaction is the best solution, at least in the short term, so the captured CO2 will be cooled down and compressed to minimise storage space requirements. The specific tank size will be vessel-specific and based on operational profiles, most importantly carbon capture rate. We know that space will be at a premium, and we are already exploring the best possibilities for fitting the system and storage tanks onboard different types of vessels.
Each vessel type will face different challenges. While container liners will have to sacrifice some space, these vessels will have the simplest installation. On the other hand, the bulk and tanker segments have more available space but require more complex piping and infrastructure to be installed.
Interview: Felix Selzer
