Effective Control of SOx and NOx Release to the Atmosphere from Emissions of Ship Propulsion Engines

Abstract

The reduction of noxious air pollution from ship discharges had been dealt with since the early of 1960s by the world’s maritime regulatory body, the International Maritime Organisation under the jurisdiction of the United Nations. The auspicious Annex VI of the Regulations 12–15 of the IMO addresses the environmental pollution issues and emission limits of SOx and NOx in particular from ship propulsion engines including ODS and VOC. This first version of the regulation had been adopted by MARPOL convention in 1997 and the subsequent revisions ratified by many nations are highlighted in this paper. As of after the first version of the regulation introduced, continuous efforts were made by the Marine Environment Protection Committee (MEPC) of IMO, there were series of improvement progression on the regulations to ensure more stringent rules adoption and to be complied by all parties concerned. Several researches and initiatives are being carried out currently and also in the past since then the period of combustible fossil fuels including hydrocarbons being used in industrial plants and ships. The effective methods of control of these emissions particularly SOx and NOx discharges from ship propulsion engines become the essence of discourse of this paper. The effective measures using seawater scrubbers had in fact been in used for sometimes in ships as quick responses and accomplishments by the parties concerned in the effort to reduce the releases of the detrimental gases and particulates to the atmosphere. The potential results from these continuous efforts of researches and initiatives undertaken by the research establishments and industries and adoption by ship operators or owners are discussed and presented herein. The method of the effective control using natural seawater scrubbers complement the costly refinery processes in producing engine fuels of low sulphur contents with less post-combustion product of NOx.