Compare two water injection and gas injection EOR processes in the Soroush oil reservoir

The first hydro-carbonic reservoirs simulation had done in 1959 by W.A.Bruce. He simulated imbibition and gravity drainage for Iranian oil reservoirs and concluded that injecting water to the Iranian reservoirs submit more recovery than gas injection. In this article simulated two imbibition and drainage mechanisms for one of the south offshore black oil reservoirs by CMG software, and we will survey the most important and effective factors on drainage recovery.Reservoir data show that reservoir must be water-wet. Our plan for modelling gravity drainage process is that, injected gas fluid in the oil reservoir (gas against oil is wetting phase) and displacing of wetting fluids (oil) wetted fluids (gas) is Schematic of drainage displacement process that during the wetting phase in reservoir rock matrix reduced and replaced by non-wetting fluid. With simulating water flooding, modelling imbibition mechanism and to be able compare these two production mechanisms, we injected water equivalent volume of gas injected to the reservoir. By IMEX (CMG) run both models and record recovery value under each production mechanism.To see the impact of the factors involved in the production mechanisms, some of the main factors studied and every time by changing a factor and getting constant the remaining cases, achieved Recovery rate by gas injection in that state, and compare with the first case. Then it became clear that initial water saturation, gravity force and fluid viscosity are the most important affecting factors on the oil recovery. Therefore, for each case a sensitivity analysis was also carried out, and the result will follow in continues. Results of the simulation by CMG show that oil production from this reservoir by water injection process (imbibition) was seven times more than recovered by gas injection (gravity drainage) respectively.

کلیدواژه ها:

imbibition ، gravity drainage ، oil recovery ، CMG software