Study of Various Injection Patterns in Water, Gas and WAG Injection Methods in an Iranian Fractured Reservoir

In the common methods of water and gas injection , high and unsuitable mobility ratio within the injected fluid and the reservoir oil, leads to viscose fingering and reduction of sweep efficiency. It was originally inteded to improve sweep efficiency during gas flooding , with alternative slugs of water and gas WAG injection designed by and large to follow the same route through the reservoir.WAG injection has been widely applied since the late 1950 s. the typical improved oil recovery IOR potential for WAG injection when compared with water injection is quoted in the literature at 5-10% . in this method , injection of water slugs followed by gas leads to triple region , increase the contact level of injected fluid and reservoir , stable the movement front , and finally increase the recovery. but depend on the conditions , type and pattern of injection , imporvement of recovery is variable and different. in this work , four possible scenarios -natural depletion, gas injection water injection and WAG injection - in four and five spot patterns were compared.

Keywords:

enhanced oil recovery EOR , simulation , water alternating gas WAG injection , gas injection , water injection , well pattern.