Research On Edge Water Energy Caculation Method And Water Invasion Mechanism In BQ57Oilfied

BQ57oilfield is a heavy oil reservoir with active edge water from southwestern areawith some problems caused by water invasion such as low oil productivity, low recoverypecent and poor development effect. It is vital to ensure edge water energy, edge waterinvasion performance and major factors during the displacement process, which contributes toput forward measures to restain water invasion pointedly.Based on static geologic data and dynamic development data in BQ57oilfield, it buildeda detailed geological model and made a history match process. Combining material balancemethod with numerical simulation method, it computed edge water energy and drawed aconclusion that the capacity of edge water is infinite. It got water invasion amount and waterinvasion rate of the whole area and each layer separately, concluding that water invasionamount and water invasion rate increase by recovery percent. Using dynamic analysis methodand numerical simulation method, it revealed the rule of edge water invasion that waterinvades by high permerbility zones, water invasion performences more seriously as closer tooil/water boundary, in addition, water invesion peformence is effected by perforationcondition and development parameters.Considering12factors during steam huff and puff process and based on orthogonalexperimental design mechanism, it set up64schemes with4levels of each facor in CMG. Itpredicted breakthrough time of each scheme, ensured the extent and weight of water invasionimpact of all factors and sorted them. It obtained the main controlling factors and theinfluence rule of them: main controlling geological factores are formation heterogeneity andviscosity of crude oil, while main controlling dynamic factores are production/injection factorand steam intake per unit thickness. Based on the result it’s got above, it optimized the maincontrolling dynamic facors（production/injection factor and steam intake per unit thickness）and got the optimal production/injection factor and optimal steam intake per unit thickness.