Prediction of Asphaltene Deposition Region in Pipeline Based on Equation of State

Asphaltene is apt to deposit from crude oil under high pressure condition, and the sediment will reduce the pipeline flow area and the performance of equipments, even block the submarine pipeline in extreme cases. The pressure is relatively high in deepwater submarine oil pipeline, so it is entirely possible to meet the condition for asphaltene deposition and pose a significant operational security challenge on deepwater submarine pipeline. In this paper, the asphaltene deposition prediction model is built based on crude oil thermo mechanics and solubility theory to predict the pressure and temperature condition for asphaltene deposition in Middle East Crude Oil and draw its asphaltene precipitation envelop. Meanwhile, the location of asphaltene deposition in an assumed deepwater submarine pipeline located from depth of 3000m to the sea level is predicted combining with the thermo-hydraulic models. The study result shows that the asphaltene deposition condition of Middle East Crude Oil and its deposition location in deepwater submarine pipeline could be predicted well by the prediction model proposed in this study. This study provides a fast and effective method for predicting asphaltene deposition in deepwater submarine oil pipeline.