Why the scrubber discussion is so important

CEO of Yara Marine Technologies, Dr Thomas Koniordos has shared his views with ShipInsight on the latest developments in the scrubber debate.

Thomas Koniordos

As an industry we need to show support for research and development to create a sustainable shipping industry. The image of shipping is somewhat hard to define. In the mainstream media there tends to be a focus on it when there is an accident or in relation to its environmental image.

More often than not the point that gets ignored is that over the years the industry has been rapidly improving, with nearly all its emissions to air and discharges to sea now being regulated, and owners, operators and technology firms working on an array of solutions to take shipping to a new level of sustainability.

All the technical efforts, both in the past and into the future, to improve shipping should be applauded. These efforts show how the industry is being progressive. But it gets confusing perhaps when we hear different solutions compared to each other.

At Yara Marine we believe that shipping is not homogenous, there is not, and nor will there be, one solution for all vessel types. This is why so many solutions, and potential solutions are needed when we focus on a sustainable future for a global industry.

About a decade ago, as bunker fuel prices began to climb and regulators began to urge ship operators to look at ways to curb greenhouse gas emissions and other emissions and discharges, operators were using a range of tools to find a balance between operational efficiency and regulatory compliance. (Onboard efficiencies are also one of the most widely accepted ways of reducing fuel consumption and therefore CO2 emissions).

Just now we are approaching the big issue of the global sulphur cap, where all ships have to have a fuel of less than 0.5% sulphur content from January 1 2019 – not as low as the ECA limit but serious due to it impacting up to 70,000 ships – or use approved systems (such as exhaust scrubbing technology or LNG) to demonstrate equivalence – a principle enshrined into the regulations of the International Maritime Organisation.

Simultaneous to the global sulphur cap impacting shipping, two other trends are developing. On the one hand is the drive to even further address shipping’s greenhouse gas emissions through additional regulation, and to find a suitable way for the industry to reduce its impact on the environment. This latter issue is more market and societally driven and is pushing for the demands for total supply chain transparency.

This latter point is going to become more important in the future. Trade flows are no longer seen simply from port-to-port, but door-to-door, and industrial processes are now viewed from start to finish. Society no longer looks at individual parts of a chain in isolation, but at how these parts impact or are influenced by each other.

In the discussion about future fuels, this means the debate is as much about the environmental footprint of the fuel from its source (the well) to its final use. Experts no longer just look at the greenhouse gas emissions when a hydrocarbon is burnt, but at the emissions from its extraction from the oil or gas reservoir until it is burnt in an engine or power station. A significant part of this GHG footprint is at the refining and distilling processes that various fuels undergo.

In looking at the difference between well-to-wake (from oil well to the power given to the propeller) compared from bunker tank-to-propeller, two different stories emerge, and this is part of a recent scientific report from the Norwegian research institute, SINTEF.

Detailed research from SINTEF showed that using a residual fuel that has not been highly refined by an oil major will, when it reaches the ship’s bunker tanks, have a lower CO2 footprint than a refined, distilled or blended product.

In a recent paper, where marine diesel, fuel oils and LNG well-to-wake emissions are compared, SINTEF noted that since the IMO agreed on the 2020 sulphur cap in 2008, industry has been aware that desulphurising residual fuels loses between 10% to 15% of the energy content in the heavy fuel oil.

The conclusion of the work shows, when viewed from a well-to-wake perspective, that a two-stroke engine burning heavy fuel oil in conjunction with a scrubber has 3% less the CO2 emissions than when the same engine is fuelled with a low-sulphur marine diesel oil.

Clearly as we see the maritime sector move towards its 2030 goal and then the 2050 goal of a net carbon neutral transport chain it needs to equate the role it plays on other industries and where it creates additional carbon pressure on those sectors.

The idea of using water droplets to scrub exhaust gases clean was first explored in the 1950’s, rapidly becoming an approved and accepted common technology in shore-based industries across the world. Many of these systems use seawater as the wash-water due to the salinity negating the need to add further chemicals.

With over 60 years continuous development and growth in shore-based electricity generation and other industrial plants, wet scrubbers and other similar technologies have been a crucial help in the continued development of society.

With such success ashore, it was a natural consideration to adjust this effective environmental technology for marine use. This happened over 12 years ago on a UK ferry, that demonstrated the ability to clean a ship’s emissions of sulphur oxides and particulate matter, as well as to make a dent in a ship’s nitrous oxide emissions.

The first commercial scrubbers on vessels began to appear in the following years, notably on a few hundred vessels that were likely to be sailing, permanently or occasionally, in the emission control areas. Vessel operators realised the benefits of installing scrubbers to ensure they could use existing fuel oils rather than to switch to more expensive ultra-low sulphur fuels, namely refined distillate products with a sulphur content of less than 0.1%.

Very few people seemed to mind the very small increase in CO2 emissions as power was directed to the cleaning system, as it was easily countered as shipowners began to look at ways to increase ship efficiency generally. But when one looks at the well-to-wake picture the CO2 picture, as explained by SINTEF, was even clearer.

Research work into the total benefits of exhaust cleaning systems needs to continue and the discussion needs to evolve in a sensible manner. Shipping, and any other industry that uses environmentally sound technologies that are focused on long term sustainability, need to be allowed to continue their research and growth, especially when such solutions make environmental and economic sense.

Shipping remains complex, but by arguing against one environmental technology in favour of another only helps reinforce the misconception that the industry does not want to do the right thing. As an industry we are in a significant period of transformation and we need to be unreservedly optimistic about our goals and efforts. There is no denying that owners need the solutions which technology companies invest heavily in finding and developing on their behalf. Therefore we need to work together.