Taking self-elevating offshore platform as research background, this paper studied the impact of firewall on risk assessment based on the Norwegian Classification Society (DNV) risk assessment software LEAK and SAFETI. Firstly, the impact of firewalls on the leakage range of oil- gas was compared, and then the diffusion of gas clouds and group risk and individual risk under different firewall heights were analyzed. On this basis, a new type of firewall structure characterized with cooling circular tube filled with water was proposed. The effect of two types of firewall on risk reduction was compared for the new type of firewall and concrete firewall, and the conclusions obtained have significant reference value for designing marine platform firewalls.
There are lots of risk sources on the offshore platform. Any carelessness may cause disaster, such as fire, explosion and other accidents. These accidents not only cause casualties and economic losses, but also bring serious pollution and damage to the surrounding environment and marine ecology (Li and Zhang,2006). Therefore, the safety of marine engineering operation environment has been concerned. In order to ensure the safety of offshore platform operations, the Nordic countries first carried out risk assessment of offshore platforms, formed a relatively complete theory, accumulated rich historical data, and developed a series of risk assessment software (Vinnem,2007). On this basis, Pulatd and Veitcha (2005) reviewed and summarized the consequences of fire in the risk assessment of offshore platforms. The domestic risk assessment research work started late, but in recent years, with the deepening of research, some research achievements have been obtained. Yu (2014) draw up the programme of risk-based inspection plan. He calculated the risk matrix of the platform system and the separate component with the results of component importance and reliability. Jiang (2016) evaluated the risk of pressure vessel on the offshore platform and verified the feasibility of the method. Wang and Li (2018) made use of the CREAM (Cognitive Reliability and Error Analysis Method) method to evaluate the fire and explosion risk of an offshore platform and predicted the probability of platform personnel error. Considering the self-elevating offshore platform, this paper aims to study the impact of firewalls on risk assessment with software LEAK and SAFETI. A new type of firewall structure, cooling circular tube filled with water, was proposed. A better fire protection and anti-impact effect could be demonstrated with the new firewall.
