In this paper, the NOx emission and the reduction technologies of NOx emission for Korean marine diesel engines are reviewed. At first, we investigate the present production status of marine diesel engines in Korea. Also, NOx emission level of marine diesel engines manufactured by four Korean engine makers is examined. Finally, the present status of the reduction technologies of NOx emission is investigated. In general, Korean marine diesel engines satisfy the current IMO NOx regulations, however the higher technologies must be studied to prepare the more severe IMO regulations of the near future.
As the recent regulations on environmental pollution have been increasingly reinforced worldwide, International Maritime Organization (IMO) adopted "Regulations for the Prevention of Air Pollution from Ships", Annex VI of MARPOL 73/78 convention, at the 3rd MARPOL Conference held in London, Sept. 26th, 1997. The regulations enter into force 12 months after being accepted by 15 States with more than 50% of world merchant shipping tonnage. (IMO, 2003) Samoa, the fifteenth State to ratify the instrument, deposited its ratification on May 18th 2004 and then the regulations are set to enter into force on May 19th 2005. Along with the global trend of regulations for marine environment pollution, new coastal emission regulation, based on Annex VI of MARPOL 73/78 and NOx technical code (IMO, 1998), is in preparation to be enacted and come into force for the NOx emission among many emissions of shipboard engines. This study is to review, based on the previous studies done by others including the author (Kang et al., 2003), the NOx emission level of shipboard engines manufactured by Korean engine makers and the reduction technologies of the NOx emission in preparation for the NOx regulation of IMO and its effectuation.