Denmark bans open loop scrubber discharges that emit environmentally hazardous substances

Denmark’s government has joined the growing list of countries taking action against open-loop scrubbers, having reached a “broad political agreement” to ban the discharge of washwater from scrubbers into its waters, starting next year. 

The ban that covers ships with open-loop scrubbers out to 22 km from the Danish coasts comes into force on July 1, 2025.

The Danish Environment Ministry said the use of open-loop scrubbers has contributed to excessive levels of a number of heavy metals and tar substances in the marine environment and that the agreement to prohibit such actions in Danish waters could reduce the discharge of nickel into the sea by up to 20% and anthracene by 7%.

“This agreement is another important step on the way to a better marine environment. Scrubber water emits a number of problematic substances, which accumulate on our seabed and are absorbed into the ocean’s food chains and end up in the fish we eat. The discharge of environmentally hazardous substances comes from many different sources, but scrubber water is a source about which we have a lot of knowledge and data, and therefore I am happy that we are now putting an end to the pollution with scrubber water in Danish territorial waters,” said environment minister Magnus Heunicke.

Ships will be required to switch to using either low-sulphur fuel or closed-loop scrubbers. The ban on closed-loop scrubber discharges will come into force in July 2029. The agreement also states that Denmark would work for a similar ban in the Baltic Sea and North Sea through the regional maritime conventions.

.Other countries, including China, Saudi Arabia, Singapore, Turkey and many European ports and regions, have already banned the use of open-loop scrubbers.