Denmark bans marine scrubbers in its waters

The government of Denmark will ban the use of open loop marine scrubbers starting on 1 June 2025 and closed loop scrubbers starting on 1 July 2029 in its territorial waters, 12 nautical miles off its coast.

Some ship owners install scrubbers on the smokestacks of their vessels. Scrubbers reduce sulphur oxide (SOx), nitrogen oxide (NOx) and particulate matter emissions.

Open loop scrubbers take in seawater, which is alkaline by nature, to wash the SOx out of the exhaust. The wash water is then discharged overboard. Closed loop scrubbers use fresh water instead of seawater. Chemicals, such as caustic soda, are added to the water to boost its alkalinity. The water from a closed loop scrubber is then passed through water treatment and recirculated. Residual product from the closed scrubbers are delivered to ports' reception facilities.

The open loop "scrubber water discharges a number of problematic substances that accumulate on our seabed and are absorbed into the ocean's food chain and end up in the fish we eat", said Magnus Heunicke, Denmark's minister of environment.

Denmark is bordered by the North Sea and the Baltic Sea. Both seas are designated as emission control areas (ECAs). Vessels travelling in the ECAs are required to burn 0.1pc sulphur maximum marine fuel, typically marine gasoil (MGO).

Scrubbers can remove about 98pc of SOx emissions. By utilizing a scrubber, vessels could burn cheaper high-sulphur fuel oil (HSFO), which typically has up to 3.5pc sulphur content, and remain ECA compliant.

The Skagen, Denmark, MGO-HSFO premium was pegged at $295/t or 52pc premium average from 1-11 April, Argus assessments showed.

European countries that had prohibited the use of open loop scrubbers in their territorial waters include: Belgium, Germany, Slovenia and Turkey. European countries that have banned open loop scrubbers in certain ports are: Croatia, England, Finland, France, Ireland, Lithuania, Norway, Portugal, Romania, Scotland, Spain, Sweden and Whales.

By Stefka Wechsler