Debate over scrubber usage to clean marine fuel emissions continues
OVER the years the shipping industry has been rapidly improving in the area of sustainable development, with nearly all its emissions to air and discharges to sea now being regulated, and owners, operators and technology firms working on a range of solutions to take shipping to a new level of sustainability
OVER the years the shipping industry has been rapidly improving in the area of sustainable development, with nearly all its emissions to air and discharges to sea now being regulated, and owners, operators and technology firms working on a range of solutions to take shipping to a new level of sustainability.
Yara Marine Technologies points out there will never be one solution for all vessel types. This is why so many solutions, and potential solutions are needed to create a sustainable future for a global industry.
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.
Nowadays, the industry is approaching the January 1 implementation of the International Maritime Organisation's (IMO) rule that all ships use a fuel of less than 0.5 per cent sulphur content or use approved systems, such as exhaust scrubbing technology or liquefied natural gas, to meet this regulation.
Simultaneous to the global sulphur cap impacting shipping, two other trends are developing, the company pointed out in a statement.
On the one hand is the drive to even further address shipping's greenhouse gas (GHG) 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 is 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.
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 carbon dioxide (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 desulphurizing residual fuels loses between 10 per cent to 15 per cent of the energy content in the heavy fuel oil.
The conclusion of the work showed, when viewed from a well-to-wake perspective, that a two-stroke engine burning heavy fuel oil in conjunction with a scrubber has three per cent less the CO2 emissions than when the same engine is fuelled with a low-sulphur marine diesel oil.
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.
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.