(85i) Mitigation of Asphaltene Deposition by Dead Oil Recycle

Asphaltene deposition is a common flow assurance problem in the oil and gas industry. Asphaltene precipitation occurs when the pressure of a crude oil system falls below the asphaltene onset pressure (AOP) which may lead to subsequent deposition and plugging of the production tubing. The AOP curve is usually obtained experimentally and serves as an input to Equation of State (EoS) models. In this work, we highlight the importance of defining asphaltene precipitation by both the AOP curve and the amount of asphaltene precipitated. Additionally, we highlight the need for an effective mitigation technique to prevent asphaltene deposition. Thus, we propose a novel chemical-free mitigation technique, where dead oil is recycled to reduce asphaltene precipitation. The stabilization effect of the dead oil reinjection was verified using a thermodynamic model (PC-SAFT EoS), where a shift in the AOP curve is observed. Depending on the amount of reinjection and the crude oil characteristics, asphaltene precipitation can be eliminated by the reinjection of dead oil.