Consequence Analysis of a Liquefied Natural Gas Leakage

Each and every quantitative risk assessment comprises some basic activities that have to be developed to allow the quantification of the risks involved in the operation of a system or process. Basically, it must be estimated the likelihood of the identified undesired events as well as the magnitude of their consequences. When analyzing the risks in the operation of a ship, the same process has to be followed. For each specific phase of the ship mission, all undesired events must be correctly determined and evaluated. Many different types of undesired events must be investigated, such as: collision, grounding, fire, and explosion. There are many techniques and much work involved in the estimation of the likelihood of the events. The same occurs for the evaluation of their consequences. The purpose of this paper is to study the consequences of a liquefied natural gas (LNG) leakage from the rupture of a pipeline from an LNG vessel during cargo loading at a terminal in the Brazilian coast. Once defined the total leaked quantity, a software will be used to calculate the consequences. The main idea is to identify all possible consequences and verify their magnitudes on the coast. This is not a simple task because it requires the comprehension of the development of the phenomena involved after the leakage. There is also the need of the identification of many variables, including the atmospheric conditions and the ignition sources, in order to verify the extent of possible cascading events. It will be taken special attention to consequences to human beings as a result of exposure to heat radiation effects from possible fires and explosions. As a preliminary study, where the likelihood of the events will not be estimated, the final objective is to use the obtained results to predict preventive and mitigating measures, in order to reduce the consequences to people on the coast.