Improving sweep efficiency of edge-water drive reservoirs using induced formation damage

• We modeled induced formation damage by LSW injection with polymer model.
• We investigated using induced formation damage as a barrier for encroaching water.
• Induced formation damage increased the ultimate recovery in edge water reservoirs.

A common problem in edge-water drive reservoirs is oil bypassing by aquifer water. The encroaching water from the adjacent aquifer overtakes oil phase and leaves a significant volume of trapped residual oil behind. Early arrival of these water fingers causes pre-mature water production that leads to well abandonment. One solution to the problem is creating a barrier against the encroaching water. In current study the possibility of using induced formation damage caused by injecting a small volume of low salinity water into abandoned wells is investigated. Formation damage as a result of injection of low salinity water into the watered-up wells creates a low permeable barrier against the water fingers. The methodology of modeling this technique using a commercial reservoir simulator is presented. The modeling results show that injection of small volume of low salinity water results in prolongation of wells׳ life which results in ~3–5% incremental recovery if compared to normal depletion.