With the stricter sulphur limits applicable from the 1st of January 2015, the marine industry now faces the challenge of adopting new technologies and/or operational practices. Introduced by the International Maritime Organization (IMO), the European Union (EU), the US Environmental Protection Agency (EPA) and the California Air Resources Board (CARB), these emission regulations aim to reduce global and local CO2-emissions caused by the shipping industry.

Critical amongst these regulations are the measures to reduce the sulphur oxide (SOx) emissions, which are inherent to the relatively high sulphur content of marine fuels. To achieve SOx regulatory compliance, ship designers, owners and operators have three general options:

  • use low sulphur residual or distillate marine fuels in existing machinery;
  • install new or convert existing machinery to operate on an inherently low sulphur alternative fuel, such as liquefied natural gas (LNG);
  • install an exhaust gas cleaning (EGC) after treatment system.

EGC-scrubbers wash the sulphur and other pollutants - such as heavy metals - out of the exhaust gases, resulting in slurry containing these pollutants, bleed-off water and other water which is automatically discharged in the water.

Many European ports and harbours are located alongside sensitive coastlines, rivers and estuaries. As such, they are confronted with Water Frame Directives, regulating water quality standards, and/or are prohibited to discharge any waste at all. This situation can complicate the use of some type of scrubbers. Confronted with austere waste discharge regulations, ships can discharge their scrubber-generated waste at a port reception facility, provided they have an on-board storage capacity.

Certain types of scrubbers operate a so-called open loop system: the water emerging from the scrubbers is automatically discharged into the sea. Although this practice complies with IMO-guidelines, national environmental legislation and standards tend to be more stringent than the commonly agreed international standards. In these cases, manufacturers need to prove that the discharge has no impact on the quality of the receiving water, which is a time-consuming process. And the shipping industry is running out of time: the stricter sulphur limits will apply as of the 1st of January 2015.