New data from the Danish Environmental Protection Agency shows that scrubber wash water is a source of hazardous substances in the marine environment. The Minister for the Environment is now seeking a ban on this use in Danish waters.
Ships use so-called scrubbers or exhaust gas scrubbers to clean the flue gas of sulphur. In open-loop systems, the scrubber water is discharged directly into the sea. The technology is repeatedly criticised because heavy metals and tar substances such as lead, cadmium, anthracene and benzo (a)pyrene can be released into the marine environment through wastewater. Calculations by the Danish Environmental Protection Agency are said to show that up to 20% of nickel emissions and 7% of anthracene emissions come from this source. [ds_preview]
“When heavy metals and tars enter our marine environment, they hardly disappear and remain in constant circulation in the sea. The substances accumulate on the seabed and in ocean food chains, which is extremely worrying for our marine environment and our health. We need to find a long-term solution to this problem,” says Denmark’s Environment Minister Magnus Heunicke.
According to estimates by the International Council on Clean Transportation, 68 million tons of scrubber wash water containing heavy metals and tar were discharged in the 12-mile zone off the Danish coast in 2020. This would make Denmark the sixth-largest discharging country in the world. To date, bans or restrictions on the use of scrubbers are in force in around 45 countries worldwide, and almost half of the regulations are implemented by ports.
The Minister of the Environment has now called on the parties in the Danish parliament to negotiate how the discharge of scrubber water can be banned. Among other things, the Minister wants to present the parties with concrete models for possible changes to the law.
The proportion of units equipped with an exhaust gas purification system (scrubber) in the container ship fleet recently reached a new high. The total capacity of container tonnage equipped with scrubbers reached 10.3 million TEU in January, corresponding to an increase of 1.8 million TEU within one year.
