(756b) Large-Scale Release and Dispersion of CO2: Experiments and Simulation

Carbon capture and storage/sequestration (CCS) has emerged as a viable technique to mitigate climate change, reduce greenhouse gases and ocean acidification, and to enhance oil or gas recovery. An important part of the CCS chain is pipeline transport of dense-phase carbon dioxide (CO₂) from large point sources to suitable storage sites. Since CO₂ is an asphyxiating gas, deliberate or accidental leak from pipelines represent a serious hazard, and realistic consequence modelling of such scenarios is of paramount importance in environmental and process safety. This paper presents results from numerical simulations of an industrial-scale pipeline release and the subsequent dispersion of CO₂ in the atmosphere. The experiment and flow model development was part of the CO2PipeHaz [1 – 3] project in the European Commission’s Seventh Framework Programme for Research and Technological Development (FP7). The length of the experimental pipeline was 260 m, and the internal diameter 0.233 m. Pure CO₂ was discharged through a 0.05 m diameter orifice located 0.5 m above ground at the end section of the pipeline. The initial temperature was 20 ^oC and the initial pressure 53 bar. The measurements included wind speed, wind direction and temperature of the CO₂ plume. Comparison between experimental results and numerical simulations with the computational fluid dynamics (CFD) software FLACS [3] shows good agreement. The numerical study provides useful insight into the dispersion behaviour of the CO₂ plume, and highlights the sensitivity towards the use of various pseudo-source models, turbulence models, and wind conditions. The paper represents a significant contribution to the understanding of hazards associated with pipeline transport of carbon dioxide.

References 

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