Effects of hydrodynamic properties on asphaltene deposition in wellbore

Abstract

In this study, order-of-one scaling analysis was employed to evaluate the effects of hydrodynamic parameters on asphaltene deposition in wellbore. Through this method, four independent dimensionless groups were determined from the corresponding momentum and mass balance equations. The dimensionless group π4 was of particular interest because of its inherent relationship to the deposition rate and sticking probability. Using π4 the existing several sets of experimental data were compared with empirical correlations and results were integrated into single plot from which trend of deposition rate was inferred.Results suggest that the rate of asphaltene deposition is a strong function of Reynolds number (Re) and fluid velocity. Moreover, there are two distinctive deposition regimes; Regime I where rate of asphaltene deposition decreases with increasing Reynolds numbers and Regime II at which the rate increases with increasing Re. The transition between these two regimes is a function of particle size. For particles smaller than 2 μm, the transition occurs when Re is greater than 160,000 and for particles larger than 100 μm, the transition occurs for Re lower than 2000. Furthermore, the outcome of the sensitivity analyses on fluid and particle properties indicate that deposition rate is strongly related to fluid viscosity and particle size.