Modeling of Asphaltene deposition during Miscible CO2 flooding

In this Article we present the results of numerical tests in order to investigate the likelihood of asphaltene precipitation and deposition during Co2 flooding in a reservoir. We examine the effects of asphaltene precipitation on oil properties such as oil viscosity and density during miscible Co2 flooding process by use of Winprop Software .we also investigate the oil properties change during Co2 miscible flooding by numerical slim tube with use of a compositional simulator (GEM). In this Study a fluid sample of one Canadian oil Reservoir (Saskatchewan Reservoir) that had been flooded miscibly with Co2, was chosen for performing the sensitivities. The results showed that asphaltene precipitation reduces the oil viscosity and density that is in favor of production. On the other hand asphaltene deposition causes resistance in oil production due to porosity and permeability reduction. The mmcompetition between these two effects, declares the effect of asphaltene on recovery that could be different for any reservoir. The results also showed that decreasing the rate of Co2 injection leads to increase in asphaltene deposition near the injective well. Due to this phenomenon in higher injecting rates the increment in well bottom-hole pressure becomes less.

Keywords:

Asphaltene , Miscible Flooding , Asphaltene precipitation , Asphaltene Deposition Introduction: