The problem of bottom water draw-off (BWDO) in pipelines carrying oil with a relatively high water cut is investigated using a computational fluid dynamic method of analysis. The conditions simulated are those obtained from field tests for a 68-cm. I.D. pipeline. The flow conditions in this pipe result in stratified flow of relatively oil-free water at the bottom and oil-in-water emulsion at the top. The oil-in-water concentration in the emulsion layer was variable across the layer. The BWDO from a single 90 deg draw-off branch was simulated. Using the model the draw-off water quality was calculated for differnt draw-off flow rates and three different oil-in-water emulsion concentrations. The flow from two draw-off pipes 5-meter apart was simulated under different draw-off flow rates and emulsion concentrations. The two tapings flow rate combinations required to produce a desired draw-off water quality were identified. Simulations with two tapings 15-meter apart was also conducted and showed similar draw-off water quality. The results obtained in this study should aid in designing BWDO systems in oil pipelines with high water cut.
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