“Releases as much zinc and copper as the base paint"
At the turn of the year, requirements for new purification systems in the chimneys of cargo vessels, the so-called Scrubbers, were introduced to reduce sulphur emissions in the air. Remarkable is that there are no regulations for how and where to clean these scrubbers. The consequence is that many times it is done directly into the sea. Scientists believe that a vessel might emit as much copper and zinc through its scrubber as from its boat bottom paint. Once again, the legislator has not understood the consequences of its own decision.
Since January 1st 2020, new emission regulations apply to all types of cargo vessels in the oceans. Meaning that the emission limit for sulphur content in marine fuels was lowered from 3.5 to 0.5 percent. In the Baltic Sea, the North Sea, the English Channel and some other places in the world, so-called SECA areas, the limit was lowered to 0.1 percent. Regardless of differences in percentages, it is exactly the same technology that the shipping industry need to invest in. The two alternatives are:
1) Installing scrubbers in the chimney. An emission purification system which allows you to continue using the high sulphur-containing bunker oil.
2) Switching to a fuel with less than 0.5 percent sulphur. This includes, for example, natural gas (LNG) and possibly methanol and gas oil (LPG). However, this is a significantly more expensive option than installing scrubbers.
A scrubber costs about SEK 50 million, installed and complete. Still, investing in one is cheaper than running on the more environmentally friendly bunker oil.
For the shipping companies it is about money. For the legislators, there are other driving forces. The primary ought to be that as quickly as possible meet the surroundings world's increasing focus on emissions and global warming. I do not see any other reason for pushing through such a legal requirement without doing a proper impact analysis, where one had seen that sulphur and other environmentally hazardous substances might be discharged into the sea.
So far, I have only seen some scientists at Chalmers warn that the effects could be very serious for the marine ecosystem. They say that the use of scrubbers does not reduce emissions, but that they are now concentrated in the sea instead of being spread with the air. When the sulphur oxides react with water and form sulphate, there will locally be a strong acidification of the sea water.
Furthermore, the scientists claim that a number of other pollutants are released from the exhaust gases, meaning that the scrubber water contains a large mixture of toxic substances. For example, scientists at Chalmers have found that a ship can emit as much copper and zinc through its scrubber as it does from the boat bottom paint.
I think the new emission regulations are great. But they are not enough. We also need legislation regarding the landfill. The sulphur must not end up in the sea or in other parts of nature.