Investigation of the N2 impurity in CO2 gas injection

miscible CO2 injection is one of the most efficient methods enhanced oil recovery the minimum miscibility pressure (MMP) as a basin parameter plays an important role in the miscible gas injection processes . In this work , a set of PVT data of an oil reservoir was selected from PVT reports of the french petroleum compant TOTALFINAELF to perform a study the effect of N2 impurity in CO2 gas mixture during EOR process. the injection of a miscible gas into the reservoir often results in complex phase behavior that can be captured only by compositional simulators. compositional simulators require accurate EOS fluid characterization to make useful predictions. in this study the whitson method was used to lump oil components and the winprop simulator was used to calculate MMP values for the selected oil sample during CO2 injection. after that , compositional simulation is carried out with GEM software and computer model slim tube was produced to examine the miscibility. recovery plots versus pressure were generated to calculate MMP. the MMP results from winprop and GEM simulator and slim tube test data were reported. the effect of N2 impurity in CO2 gas mixture injection was also simulated and investigated.

Keywords:

CO2 injection , miscible displacement , minimum miscibility pressure , N2 impurity , simulation.