Review of sulphur emission from international shipping - effects and regulatory global abatement steps

Abstract

On October 27, 2016, International Maritime Organization (IMO) announced enforcement of its Revised Annex VI rule, also known as IMO Global Sulphur CAP 2020, to be implemented from January 1, 2020. In an effort to reduce air pollution, especially Sulphur emission, ships will have to use marine fuels with Sulphur content of not more than 0.5%S m/m (Mass by Mass) against current existing limit of 3.5%S m/m for outside the Emission Control Areas (non-ECA) and 0.1%S m/m content for the Emission Control Areas (ECA) will remain as 2015 standard. The regulation implies that ships may use distillates or fuels with less than 0.5% Sulphur (desulphurised HFO), liquefied natural gas (LNG), bio-fuel or continue to use residual fuel with high Sulphur content with an approved exhaust cleaning system installed on board. Both options entail large investment for the ship owners. While scrubber retrofit requires feasibility study with existing engine plant and layout with huge initial capital expenditure for the installation of plant, continuous low Sulphur operation option poses high operational cost due to projected distillate fuel price hike to incorporate with supply and demand in future. On the other hand, LNG and other fuel options for shipping industries fuel demand fulfilment are very lean and immature to date. This paper contains an overview of international shipping emission, particularly Sulphur effects on the environment, and justification on IMO regulatory steps for global sulphur abatement with options for the ship owners to comply.