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Abstract
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Gas condensate reservoirs are recognised as an important category of hydrocarbon reserves, which provide a considerable amount of gas for various uses in commercial, industrial, and residential sectors across the world. A common operational issue occurring in gas condensate reservoirs is the condensate loss, particularly in the vicinity of the wellbore, leading to the liquid blockage phenomenon. Among several solutions proposed for the condensate recovery, the gas injection strategy is of great interest in terms of practical prospect, due to the availability of gas and achievement of fairly high condensate recovery. In general, most of modeling/simulation investigations on condensate recovery processes assume local equilibrium to model mass transfer rate of components involved in the interphase mass transfer phenomenon. This assumption does not seem realistic, since high fluid velocity and limited contact area around the wellbore result in an apreciable deviation from the equilibrium condition. In this study, vaporization of liquid condensate components into the flowing gas stream is explored through experimental and modeling approaches. We take into account the non-equilibrium interphone mass transfer. A key parameter in the non-equilibrium mass transfer is the mass transfer coefficient. Lack of laboratory data concerning the vaporization of condensate components into the gas phase motivated the authors to conduct a systematic experimental work. Taguchi design of experiment (DOE) is imlemented to optimize the exeriments in terms of number of runs and process conditions. To accurately estimate the mass transfer coefficient, the diffusion/dispersion and convection mass transfer mechanisms are incororated in the modeling of condensate vaporization in porous systems for the first time. The statistical tests are also employed to assess the relative importance of diffusion/dispersion and convection mechanisms in the condensate vaporization process. The optimum level of d
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