Discharging high-sulphur wastewater from scrubbers in Malaysian waters will be prohibited, Malaysian maritime authorities announced.
The use of open-loop exhaust gas cleaning systems (‘scrubbers’), which discharge high-sulphur waste, within 12 nautical miles of Malaysian land will be prohibited.
Shipowners will have to use low-sulphur fuels or closed-loop scrubbers in Malaysian waters. Vessel traffic in Malaysian waters is high as Malaysian ports are key bunkering hubs, where ships go to refuel.
Other regions where open-loop scrubbers are banned include China, Singapore, Fujairah and the Panama Canal.
Shipowners have been installing scrubbers in their vessels to comply with the International Maritime Organisation (IMO)’s 0.5% cap on sulphur content in marine fuel emissions, which comes into force on 1 January 2020.
Scrubbers remove sulphur from a ship’s emissions so a ship can continue to use marine fuels with 3.5% sulphur content, the current industry standard.
Open-loop scrubbers use seawater to neutralise the sulphur oxide in gas emissions and discharge the wastewater back into the sea. Closed-loop scrubbers use seawater mixed with sodium hydroxide or another reagent to neutralise the sulphur oxide in gas emissions and are fitted with a tank to hold the resulting wastewater.
Open-loop scrubbers have proved controversial. Earlier this year, Japan’s Ministry of Transport announced its view that discharge from open-loop scrubbers do not cause significant damage to marine ecosystems.