Discussion of thermal experiments’ capability to screen the feasibility of air injection

• Discuss the roles of thermal experiments (mainly TGA and DSC).
• Collect kinetic data from thermal experiments.
• Present workflow to use thermal experiments.
• Present application of kinetic data.

Thermal experiments such as thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), accelerating rate calorimetry (ARC), and small batch reactor (SBR) are typically used to screen the feasibility of air injection in a reservoir. In this paper, the capability of these tools were studied. The screening criteria for air injection process (AIP) based on the thermal experiments were summarized. A practical workflow to use the thermal experiments to build a base simulation model for AIP it was proposed. In an AIP simulation model, there are about 12 variables to govern the process. Generally, researchers consider kinetic data as adjustable variables to match experimental or field data. How to properly adjust the kinetic data and understand the effect of the kinetic data on the production performance of a reservoir are not well established. In this paper, the reaction temperature ranges and the exothermic peak temperatures for the low temperature oxidation (LTO) stage and high temperature oxidation (HTO) stage were summarized from the experiments using 19 crude oils. The measured kinetic data of 22 different crude oils, and the kinetic data of 25 sets of crude oils with the presence of additives were also summarized. From these data, the ranges of activation energy and frequency factor were defined as the reference for future studies, if such data are readily available. A simulation study has been conducted to study the significance of the kinetic data on production performance. It is observed that the variation of the activation energy significantly influence the recovery performance while the variation of the frequency factor does not.