Risk and Reliability Analyses for Innovative LNG Offshore Floating Units

The development of the Liquefied Natural Gas (LNG) offshore industry is viewed as a major improvement in the exploitation of the world’s energy resources. Most energy analysts agree that significant increases in Natural Gas (NG) demand is expected in the next decades due to relatively low prices and an important gas quantity worldwide. In order to develop the use of this resource, many innovative offshore floating installations have been developed and are currently deployed all over the world. However, hazards linked to LNG and due to hydrocarbon releases are not always so well understood or controlled. Thus, in order to quantify and understand these risks associated to LNG treatment or containment as well as their consequences, a number of different types of risk and reliability engineering techniques can be used at different stages of the project. The following will present specific analyses that have been performed on innovative LNG Offshore floating units to provide a qualitative and quantitative hazard assessment by predicting the consequences and the frequencies of these hazards, while improving the reliability of the installation and its availability. The paper will first introduce the LNG offshore industry outlining the different installations possibilities and the associated hazards. Then, based on recent projects, it will detail the risk-based methodology applied to ensure the safety and the profitability of such innovative installations when no rules are able to frame fully the development of these projects. Finally, after having pointed out the ins and outs of risk studies, a case study using most of the methods presented previously will be developed.