EVALUATION OF CO2 INJECTIVITY FROM WATERFLOOD VALUES

Description: Injectivity index values from fields which have undergone waterflood operations are compared to injectivity index values from the same field while undergoing CO2 flood operations. A number of different methods for evaluating the indices are presented. Application: Aiding in the design of CO2 floods by estimating the CO2 injectivity value from data from secondary operations. Results, Observations and Conclusions: The correlations developed have been verified ‑ with good accuracy ‑ on injectors which were brought on later in the same field. It was also observed that the rates calculated from this correlation were in closer agreement to actual injection rates, than those predicted by theoretical formulas. Significance of Subject Matter: Carbon dioxide flooding is a very common tertiary recovery IOR method employed in fields which have relatively easy access to CO2. In some cases, estimating the CO2 injection rate is often the most important design parameter which decides the planning, field implementation and eventual success of a flood. This paper presents a method for evaluating this important parameter from data that should be readily available for a field.