Oxidation kinetics of North Sea light crude oils at reservoir temperature

Air injection into deep, light oil reservoirs is a potential technique for large scale improved oil recovery. The feasibility of an air injection proc ess relies on complete consumption of oxygen from the injected air to achie ve a nitrogen flood. In this study, the oxidation kinetics of light crude o ils was investigated at typical reservoir temperatures (90-140 degrees C), and high pressures. The oxygen consumption rate was measured from the reduc tion in the oxygen partial pressure using a small batch reactor (SBR). Meas ured pressure data for different crude oils was used to establish a simple reaction rate model of acceptable accuracy for reservoir simulation. At the relatively low reservoir temperature of the experiments, the main gaseous product from the reaction was carbon dioxide. Additional experiments were p erformed in a high pressure oxidation tube (0.1 m diameter and 1.5 m long). The oxidation rate data obtained was used to validate the reaction rate mo del. The low temperature oxidation (LTO) scheme and its implications for th e Air Injection LTO Process are discussed.