“It is an unprecedented solution, a world first”, assured Marc Reverchon, president of the company, aboard the Piana on which is written roughly “first ship in the world zero particle”.

It is “equipment that is totally innovative in the maritime world”, outbid Stanislas Lemor, CEO of Stef, specialist in cold logistics, which owns La Méridionale.

This filter, currently installed on the four engines of the Piana, eliminates 99% of sulfur oxides (SO2) but also 99.9% of fine and ultrafine particles, among the main air pollutants emitted by ships.

“They go much further than what is required by the regulations, by treating all particle emissions”, commented to AFP Damien Piga, director of external relations and innovation at AtmoSud, a regional organization for monitoring the quality of the air.

Since 2020, the sulfur content of marine fuels has been limited to 0.5%, compared to 3.5% previously, according to regulations from the International Maritime Organization (IMO). And from 2025, it will even be limited to 0.1% in the Mediterranean.

When La Méridionale launched the experiment in 2018, it was looking for a process to comply with these regulations “because we did not want to install scrubbers”, detailed Christophe Séguinot, technical director of La Méridionale.

Scrubbers, equipment placed on the chimneys of ocean liners, which consists of washing the smoke with seawater, are disputed because most shipowners are equipped with them opt for an open circuit, with discharge of pollutants into the sea, rather than ‘a closed system, where filtered sulfur is stored on board ships.

The particulate filter developed by La Méridionale uses a principle already proven in thermal power stations, for example: sodium bicarbonate powder is injected at the engine outlet, into the exhaust gas manifold.

The bicarbonate will react chemically with the particles present in these exhaust gases, then end up in a filter made up of bags, on which it will settle and capture the particles and heavy metals.

As early as 2016, La Méridionale – which provides freight and passenger transport between Marseille, Corsica and Morocco – was the first ferry company in the Mediterranean to electrically connect its ships to the quay in Marseille to limit polluting emissions.