On November 30, 2018 Singapore’s Maritime and Port Authority (MPA) declared that, with immediate effect, the discharge of wash water from open-loop exhaust gas scrubbers in the port of Singapore would be prohibited.
The IMO’s global sulfur cap bans ships from using fuels with a sulfur content above 0.5% from January 1, 2020, compared with 3.5% now. To comply with the new rules, ships will be required to burn marine gasoil, low-sulfur fuel oil, or shift to alternative fuels like liquefied natural gas. In anticipation of paying higher prices and uncertainties about the availability of these fuels, many owners have opted to invest in exhaust gas cleaning systems, or scrubbers.
Open-loop scrubbers use seawater as the medium for cleaning a vessel’s exhaust. The seawater is usually supplied by a dedicated pump. Carbon dioxide is added to create a cleaning compound. As of January 1, 2020, ships fitted with open-loop scrubbers calling at Singapore will be required to use compliant fuel or switch to a closed-loop mode of operation if fitted with hybrid scrubbers.
In the German section of the River Rhine, Belgium and the US Commonwealth of Massachusetts the use of open-loop scrubbers has been banned. Recent reports suggest that China may be the next to outlaw open-loop scrubbers on its rivers. Similar bans may well be imposed in the ports of other nations.
These announcements are troubling for owners who have already invested millions in exhaust gas cleaning systems in anticipation of the IMO sulfur cap in 2020. The open-loop scrubber system has been the preferred option for most shipowners who have chosen scrubber installations, which are seen by many as the most practical and economic solution. Data shows that nearly three-quarters of the total systems installed are open-loop systems, the majority of which are closed-loop-ready (convertible into a closed system at a later stage). Hybrid scrubbers account for 22% of the total, while closed scrubbers account for only 2%.
Members with ships fitted with hybrid scrubbers are recommended to carry out a switch to either a closed-loop mode or to compliant fuel prior to arrival in relevant port waters. Your Managers recommend that Members take note of this information and be guided accordingly. If any elaboration of the foregoing is required, your Managers will be pleased to assist.