With increasing interests in using LNG as a marine fuel, safety issues for LNG bunkering have brought about global discussion on establishing a safety exclusion zone around LNG bunkering areas. However, international consensus has yet to be reached in determining an appropriate extent of the zone to ensure safe liquefied natural gas (LNG) bunkering. The purpose of this study is to identify potential risks of LNG bunkering and to present a statistical method for determining the safe exclusion zone around LNG bunkering station with the help of a purpose-built computer program, integrated quantitative risk assessment (IQRA). A probabilistic risk assessment approach was adopted in this study to determine the safety exclusion zone for two case ships: one, a 300,000 DWT very large ore carrier (VLOC) and the other a 32,000 DWT bulk carrier. The results are then compared with those obtained by a deterministic approach and the discrepancies are discussed. It was found from this study that the frequency of bunkering is one of the key factors in determining the extent of safety exclusion zone. Thus, a somewhat surprising result of 36 m radius safety exclusion zone for the 32,000 DWT bulk carrier compared to 6.4 m radius for the 300,000 DWT VLOC was obtained. It was also found that the deterministic approach produced a much more extensive safety exclusion zone for the 300,000 DWT VLOC subjected to infrequent large-scale LNG bunkering operations compared to the probabilistic approach, while it was reasonably consistent with the probabilistic approach for the 32,000 DWT bulk carrier which uses frequent small-scale bunkering

No abstract

With strong environmental and economic driving forces for using LNG as a marine fuel over the last decade, an increasing number of local/international ports, mainly in Europe, have initiated LNG fuel providing service to LNG-fuelled ships. This trend is now spreading throughout the world. The LNG bunkering methods currently in use are truck-to-ship (TTS), ship-to-ship (STS) and pipeline-to-ship (PTS). This paper describes a study conducted to identify potential risks associated with LNG bunkering with particular emphasis on the fuel-supplying side. A series of parametric analyses were also carried out to identify the sensitivity to some parameters with the aid of a purpose-built computer program, Integrated Quantitative Risk Assessment (IQRA). Through the parametric analyses, general relationships between the risk and various parameters could be established from which the importance of the selected parameters might be evaluated. This paper also proposes a new approach of establishing realistic safety exclusion zones in LNG bunkering process. Research findings demonstrate that the implied hypothesis that the current practice of the probabilistic risk assessment focused on the populationindependent analysis only is somewhat inadequate when applied to determining the safety exclusion zones as showing that the extent of safety exclusion zones tends to be set up unpractically wide. Instead, the proposed approach designed with the combination of population-dependant and independent analyses is proven to be useful in determining the zones more realistically. It may form a basis on which more useful safety-related standards and regulations on LNG bunkering can be built.

In response to the impending international maritime regulation, MARPOL Annex VI Reg. 14, to curb sulphur oxides (SOx) arising from shipping activities, this paper aimed to evaluate the environmental impacts of the entire life cycle of three different SOx reduction scrubber systems: (1) 'wet open-loop', (2) 'wet closed-loop', and (3) 'wet hybrid'. To achieve this goal, the paper developed 'the Parametric Trend Life Cycle Assessment (PT-LCA)' which was introduced to proceed the extensive analysis for a number of case ship studies and quantify various emissions, such as greenhouse gases (GHG), sulphur oxides (SOx), nitrogen oxides