Influence of ferrous iron on the oxidation of crude oil at a low temperature

摘要

Air flooding can be successfully applied in a low-temperature reservoir due to the existence of ferrous ions in formation water. However, few published papers can be found about the mechanism of oxidation of crude oil on condition with Fe2+ at a low temperature, by far. Therefore, in order to reveal the mechanism, some static oxidation experiments are carried out at 30 degrees C in this paper. On condition with Fe2+, the rate of oxygen consumption is increased by 2.3times as that on condition without Fe2+, and the concentration of O-2 in the air is decreased to 7.5% after oxidation. According to the results of the changes in the compositions of the air and the crude oil, not only can Fe2+ accelerate the rate of the oxidation but can also affect the pathway of the oxidation. The experimental results can provide a basis for how to further improve the development effect of air flooding in Ganguyi oilfield and safely make use of air flooding in other low-temperature reservoirs.