Two different crude oils with significantly different physical properties, South Pelto Crude Oil and Garden Banks Condensate, were studied extensively in the small-scale flow loop of Tulsa University Paraffin Deposition Projects. A total of eight oil-water deposition tests, two single-phase deposition tests, and two inversion point tests were successfully conducted. Four different water cuts were selected for each fluid.

The deposit thickness showed a decreasing trend with increasing water cuts for both the South Pelto oil and Garden Banks condensate tests. In contrast to South Pelto's water continuous results, which showed no deposit, a Garden Banks condensate test with 85% water cut did generate a very thin and hard deposit film. This result indicates that there has to be a different deposition mechanism than the ones based on conventional diffusion theory. A reduction in Reynolds number caused by the increased apparent viscosity of the mixture also resulted in a lower paraffin content of the deposits. The volume fraction of water in the deposit is lower than the initial water cut of the mixture for both fluids. Garden Banks showed less water fraction in the deposit compared to South Pelto.

Couto's (2004) preliminary oil-water paraffin deposition model was validated against experimental data. Several modifications are proposed to account for water concentration in the deposit and changes in the diffusion coefficient for water dominated flows. Model predictions agree fairly well with experimental data acquired in this and previous studies.

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