A Three-Phase Integrated Asphaltene Deposition Model in Oil Wells

Abstract

Abstract This paper investigates asphaltene deposition in an oil well produces from a deep Jurassic reservoir located in Kuwait by developing a three-phase asphaltene deposition integrated model. The objective of this study is to develop and validate an integrated well model that incorporates asphaltene thermodynamic, aggregation, deposition, and transportation models coupled with a three-phase thermal-hydrodynamic mechanistic model. The proposed model is numerically solved to predict temporal and spatial asphaltene deposition and concurrently tracks oil composition changes due to asphaltene deposition. The elemental models of the integrated model are tuned against field data, and the deposition result is validated with a caliper log data. The field validation study revealed a very good match between the measured deposition behavior and model predictions. In addition, sensitivity analysis showed that although asphaltene precipitation increases as water cut increases due to higher pressure drop, asphaltene deposition decreases due to increasing shear stress and decreasing asphaltene sticking tendency on the pipe wall. Furthermore, sensitivity analysis revealed that as GOR increases, asphaltene precipitation increases; however, asphaltene deposition decreases. The proposed model shows significant sensitivity to asphaltene particle diameter, revealing that as particle diameter increases, deposition thickness decreases.