Heat exchange with surrounding formations and Joule-Thomson (JT) cooling during CO2 injection into deep saline aquifers and depleted hydrocarbon reservoirs can lead to substantial declines in well injectivity. This work introduces an analytical model for nonisothermal CO2 injection that accounts for both JT cooling and interformation heat exchange, assuming that heat transfer begins upon arrival of the temperature front rather than the gas/water front, as adopted in earlier models.
Introduction
Temperature and pressure profiles provide important information about reservoir behavior during CO2 injection. Analytical models can provide such information more quickly with less computational expense. Additionally, the analytical models yield significantly faster inverse solvers, where iterative procedures include forward runs; thus, the inverse solutions for interpretation of laboratory corefloods and improved reservoir characterization from field data are more effective under analytical modeling.
