Establishment Of Reservoir Flow Field Evaluation System And Research Of Improving Recovery

Most oilfields are developed with water-flooding in China. There is one common problem when the oilfields are developed to the last stage. The long-term water-flooding makes inhomogeneous change of the reservoir flow field, causing the futile cycle of the flooded water. Therefore, it is very necessary to build a reservoir flow field evaluation systems to guild the late time adjustment.There is no thorough reservoir flow field theory and no unified flow field evaluation index so far. The research of reservoir flow field is restricted to two-phase reservoir. In this paper an unified flow field evaluation index is filtrated and a three-phase reservoir flow field evaluation systems is built. Apply this system to an actual oilfield to guild the development of this oilfield. There are such creative contents in the research:1. Analyze the influence factors of the reservoir flow field change and filtrate the flow field evaluation index, which is concise and representative. The filtrated evaluation index can both represent water phase and gas phase flow field change.2. Build a three-phase reservoir flow field evaluation systems based on the filtrated evaluation index and characterize the reservoir flow field quantitatively. Grade flow field strength to four levels: strong predominant flow field, predominant flow field, weak predominant flow field and non- predominant flow field.3. Summarize and analyze the influence that long-term water flooding makes to the reservoir. Establish corresponding relationship between the influence degree and the filtrated evaluation index, which is described in the numerical modeling.4. Apply the reservoir flow field evaluation system to an actual oilfield and analyze the relationship between the distribution of the predominant flow field and the remaining oil. Optimize the best adjustment scheme with a satisfied effect.