Effect of gas composition on dispersion characteristics of blowout gas on offshore platform

  • Yang, Dongdong (Centre for Offshore Engineering and Safety Technology, China University of Petroleum (East China)) ;
  • Chen, Guoming (Centre for Offshore Engineering and Safety Technology, China University of Petroleum (East China)) ;
  • Shi, Jihao (Centre for Offshore Engineering and Safety Technology, China University of Petroleum (East China)) ;
  • Li, Xinhong (Centre for Offshore Engineering and Safety Technology, China University of Petroleum (East China))
  • Received : 2018.07.20
  • Accepted : 2019.02.19
  • Published : 2019.02.18


Gas composition has a significant impact on the dispersion behavior and accumulation characteristics of blowout gas. However, few public studies has investigated the corresponding effect of gas composition. Therefore, this study firstly builds the FLACS-based numerical model about an offshore drilling platform. Then several scenarios by varying the composition of blowout gas are simulated while the scenario with the composition of "Deepwater Horizon" accident is regarded as the benchmark. Furthermore, the effects of the gas composition on the flammable cloud volume, the influenced area of flammable cloud, the influenced area of hydrogen sulfide and the critical time of the hydrogen sulfide spreading to the living area are analyzed. The results demonstrate that gas composition is a driving factor for dispersion characteristics of blowout gas. All the results can give support to reduce the risk of the similar accidents incurred by real blowouts.


Supported by : China University of Petroleum


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