Optimization Research of Injection-Production Mode in Fractured Buried Hill Reservoir

Abstract

Oilfield Z in Bohai bay is a fractured buried hill reservoir. Different from conventional sandstone reservoirs, the reservoir space is mainly divided into matrix and fracture system, which are quite different in reservoir physical properties and porous flow mechanism. It is easy to cause intra-layer interference of reservoir in the process of water flooding development. In order to improve the water flooding development effect in oilfield Z, and solve the problem of intra-layer interference of fracture and matrix system. Taking the actual characteristic parameters of oilfield Z as reference, the development effect of oilfield under different injection-production modes is predicted by numerical simulation software. The results show that under the mode of weak injection and forcible production, the swept volume of water flooding in the model is the largest and the remaining oil distribution is the least. In order to verify the reliability of the numerical simulation results, three-dimensional physical simulation experiments was carried out, which simulate the development effect under different injection-production mode. The results show that the water-free recovery period is longer, the water cut rises slowly and the oil recovery is higher under the mode of weak injection and forcible production. The results of physical experiments are consistent with those of numerical simulation. The research results are applied to actual oilfield production. The injection-production mode in the original scheme has been adjusted. Compared with the original scheme design, the effect of oilfield development is improved, and the increment of daily oil production for average single well reaches 83 m3. It can provide a reference for the study of injection-production mode in fractured buried hill reservoirs of the same kind.