Kinetic study of asphaltenes phase separation in supercritical water upgrading of heavy oil

Supercritical water upgrading heavy oil is a promising way to produce light oil and gas. To understand the reactions pathways and the role of supercritical water during the upgrading process, experiments were carried out in a batch reactor at 380-440 degrees C and reaction times up to 2900 min. The products were classified as gas, coke and liquid products which were further separated into saturates, aromatics, resins and asphaltenes. A kinetic model including aromatics and resins partially dissolved in both supercritical water phase and oil phase was developed. This model could fit experimental data well and interpret effects of supercritical water solubility for aromatics and resins on heavy oil upgrading process. Further, supercritical water upgrading process was divided into three stages: pre-induction primary cracking stage, post-induction primary cracking stage and gas -generation stage. This work provides an in-depth understanding of mechanism of heavy oil upgrading in su-percritical water.

Automated summary

Supercritical water is a promising method for upgrading heavy oil to produce light oil and gas. This study conducted experiments in a batch reactor to analyze the reaction pathways and the role of supercritical water in the upgrading process. The products were classified into gas, coke, and liquid products, which were further separated into saturates, aromatics, resins, and asphaltenes. A kinetic model was developed to explain the effects of supercritical water solubility on heavy oil upgrading, and it successfully fit the experimental data. The supercritical water upgrading process was divided into three stages: pre-induction primary cracking stage, post-induction primary cracking stage, and gas generation stage. This study provides a comprehensive understanding of the mechanism of heavy oil upgrading in supercritical water.