In 2016, shipping company Carl Büttner launched a pilot project to assess the technological potential of desulfurization on the high seas in a practical trial. Subsequently, ocean tanker M/T Aurelia was fitted out with a desulfurization system.
Sources of sulfur such as the main engine, the auxiliary diesel and the boiler were connected to the system and operated under varying conditions.
The technology, supplied by Bilfinger Engineering & Technologies, uses an absorption process to remove the sulfurous flue gases emitted by the ship. In this way, the ocean tanker meets the latest environmental standards.
After only around three months of operation, the reference project on board the 2006-built tanker was awarded the International Air Pollution Prevention Certificate by certification company DNV GL on behalf of the German flag in spring 2017.
In autumn 2016, the International Maritime Organization (IMO) adopted a resolution to broaden the rules for maritime environmental safety. Prior to this, the Marine Environment Protection Committee (MEPC) had conducted a study to determine the worldwide availability of low sulfur fuels and desulfurization technologies, also known as scrubbers. This study identified a large number of suitable uses for scrubbers.
In addition, a decision was made concerning the date on which the international sulfur limit of 0.5 percent is to be applied. This threshold is now to become binding on January 1, 2020. The North and Baltic Seas, as well as North American coastal waters, have been identified as sulfur emission control areas (SECA), for which a maximum of 0.1 percent has applied since 2015.
“The IMO’s decision is forcing us shipowners to either use expensive low-sulfur fuel or to install scrubbers on board to filter out the sulfur,” Lars Bremer, managing director of Carl Büttner Shipmanagement, explained.
The scrubber supplied by Bilfinger is a hybrid system that operates in different modes, i.e. in either an open or a closed loop. With the system placed in operation without any major incidents, the technology went on to prove itself in the three-month test phase.