EOR Screening and Optimizing Study on Carbonate Reservoirs

By times, production of oil will decrease eventually. Not all the oil in the reservoirs
will be produced during the process. A substantial amount of oil will remain in place
or is called as residual oil saturation (Sor) due to a partial sweep of the reservoir and
oil is trapping by capillary forces in the invaded zones. Therefore, researches have
been developed and Enhanced Oil Recovery (EOR) is the trusted technology to
improve the production and recovery in the oil fields. The objectives ofEOR are (1) to
improve the sweep efficiency, by reducing the mobility ratio between injected and inplaced
fluids, (2) to eliminate or reduce the capillary forces and thus improve
displacement efficiency, and (3) to act on both phenomena simultaneously.
Different fields acquire different methods of EOR. Hence, in order to fmd the best
method, a screening process has been done. The criteria and properties of both
method and reservoirs are taken into account in order to choose the exact method for
the specific reservoir. The properties are based on the successful field projects and
continuous research. In this project, which is focusing on the carbonate reservoirs
lithology,all the EOR methods and fields properties will be screened by using two
methods which are (1) manual screening and (2) by using EOR screening. EOR
screening is software that has been developed by the author using the macro visual
basic in Microsoft Excel2007. About 48 previous projects in carbonate reservoirs'
field has been tested using this software and the result shows gas injection as the
mostly suitable method for this lithology.