Vahid Sajadian - Research Institute of Petroleum Industries, Polymer Science and Technology Division, Tehran
Arezoo Rezaei
Mahmood Hemmati
Seyyed Saeed Ghorashi

The Water-Alternating-Gas (WAG) injection was originally proposed as a method to improve sweep of gas injection mainly by using water to control the mobility of displacement i.e. efficiency ofgas flooding with an improved macroscopic sweep by the injection of water.In this experimental study, the displacement efficiency of water injection is compared with WAG injection in scaled physical model. Also effect of different parameters such as type of oil and gas, slug size, water gas ratio andinjection rate on performance of WAG process are investigated. Comparisons the experimental resultsshows that the ultimate recovery was sensitive to the WAG ratio, flow rate and type of gas injection. Itwas also found that the immiscible Nitrogen WAG injection had less recovery compared with CO2 WAG injection

WAG, Water-Alternating-Gas, Physical model