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There is a risk of hazardous releases of CO 2 from Carbon Capture and Storage (CCS) facilities and infrastructure. To predict the exposure to the environment and to perform safety assessments, reliable and efficient simulation technology for detailed prediction of CO 2 dispersion in realistic, complex environments is needed. Here the development of an advanced industrial CO 2 dispersion simulation tool based on the CFD simulator KAMELEON FIREEX KFX ® is discussed. The tool's capability of predicting CO 2 dispersion at realistic conditions has been demonstrated through relevant tests and comparisons of simulation results to experimental data from both laboratory tests and large-scale field trials.

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TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractWater is an efficient and environmental friendly means to mitigate and extinguish fires. However, it is not easy to judge the efficiency of water based mitigation and extinction systems due to complexity of the physics and geometry. Therefore advanced computation systems, like Kameleon FireEx KFX ® , must be utilized for a prediction of the interaction between the fire, its environments and the water droplets.

A study has been performed to investigate the efficiency of Kameleon FireEx, a three dimensional transient simulator for fire and gas dispersion scenarios. Kameleon FireEx can handle hydrocarbon pool and jet fires within complex geometry, solving problems typical of oil and gas companies. The code has been developed by SINTEF Energy Research Division Applied Thermodynamics and Fluid Dynamics, within a Joint Industry Project sponsored by Ruhrgas, Gaz de France, Statoil, Elf and ENI. The paper presents some validation cases of the code, carried out with the support of full-scale measurements. A natural gas release from a vertical vent stack is considered: six jet fires resulting from the ignition of subsonic releases and ten unignited gas dispersions (two sonic jets included). The size and the shape of the flame obtained are realistic and close to the measurements. The radiation levels predicted show a good agreement with the experimental data, even though in some cases the differences between Kameleon FireEx and the measurements are significant. The gas concentrations, resulting from subsonic releases, are calculated with reasonable agreement with experiments, while the use of a simple pseudo diameter method for the sonic jet release results in overestimated plume sizes. Introduction Oil and gas industry commonly deals with highly dangerous substances, able to cause severe and extensive damage to personnel, environment and structures: fires and explosions are probably the greatest hazard that can be encountered in a process plant, concerning every stage in the production, transportation and storage systems. The present paper describes and discusses gas dispersions, eventually ignited in controlled fires, aiming at a safe disposal of flammable gases in oil processing plants. The gas emission can occur in the form of simple dispersions in the atmosphere of the gas itself released from vertical stacks (venting operations) or more often, it can take place through deliberate ignition of the gas discharged. The fulfillment of the safety design requirements demands to predict the behaviour, especially in terms of radiation loads, of controlled fires induced deliberately or originating from dispersing gas ignited accidentally. In this context, the computational fluid dynamic code Kameleon FireEx is an essential tool: it was widely used to simulate a great variety of different jet-fires and gas dispersions, also documented in a series of full-scale experiments. These large set of simulations gives also the opportunity to produce a validation of Kameleon FireEx, that showed a reasonable agreement between predictions and measurements. Kameleon FireEx Models The mathematical models used in Kameleon FireEx derive from the theory of continuos fluid mechanics. The equations governing the motion of a viscous compressible fluid are based on the three principal conservation laws for mass, momentum and energy, that most completely describe homogeneous (single continuum phase) fluid flow. At the base of turbulence modeling, there's the Energy Cascade, where the turbulent field of motion is described as a tangle of vortex elements, highly unsteady, with a wide spectrum of eddy sizes and a corresponding spectrum of fluctuation frequencies.