An Improved Linear Chemical Model for Alkaline Steamflooding

ABSTRACT Laboratory displacement tests using alkaline steamflood and conventional steamflood were successfully conducted. The results from the experiments were used to obtain correlation equations which in turn were used to simulate oil recovery performances. A chemical displacement model which incorporates the thermal and chemical oil recovery mechanisms was used to history match the experimental oil recovery performances. The model prediction of the oil recovery performances matches fairly well with the experimental results. Furthermore, the model was tested with data obtained from the displacement tests and it led to some modification and adjustment until its application for history matching and prediction became satisfactory. The model predicts higher oil recovery for caustic steamflooding over conventional steamflooding and agrees quite well with the experimental results obtained. The experimental results show that caustic steamflooding recovers more oil with increase in temperature, but above 300°F the incremental oil recovery becomes insignificant. The optimum temperature for enhanced oil recovery by caustic steamflood seems to be about 300°F. At a given temperature caustic steamflooding recovers more oil than conventional steamflood by between 18 to 35% and 8 to 13% of the original oil in place for primary and secondary recovery processes respectively.