双229—洼111区块深层特低渗强水敏油藏开发

Development of Ultra-Low Permeability and Strong Water Sensitivity Reservoirs in Deep Strata of Shuang229-Wa111 Blocks

双229—洼111区块新增探明石油地质储量大,但品位低,新井投产后产量低且递减快,经济效益差,难以实现储量快速动用与大规模建产。按照整体部署、分批实施的开发原则,优选储集层稳定区域开辟效益建产试验区。针对储集层埋藏深、物性差、倾角高的特点,利用控制变量法,采取分组类比的方式,将室内可行性研究与矿场实践结合,分别就储集层改造和能量补充方面开展探索。结果表明,与不压裂、常规压裂、常规分层压裂和高液量压裂相比,分簇缝网压裂投产效果较好,而直井大排量低砂比压裂可进一步提高投产初期产量;相比水驱,顶部注天然气近混相重力辅助稳定驱可提高采收率6%,可作为研究区最有效的补能方式。通过分簇缝网压裂提高油井初期产量,利用注天然气近混相重力辅助稳定驱有效控制产量递减,可实现该区块低品位储量的效益开发。

Shuang229-Wa111 blocks are typical blocks with abundant incremental proved OOIP.Due to the low quality of the oil,there are some problems encountered in new production wells such as low productivity and rapid production decline and it is difficult to realize rapid producing of reserves and large-scale oil production in this block.In accordance with the development principle of overall deployment and implementation in batches,optimal reservoirs are selected to establish a test area.Aiming at the characteristics of deep burial,poor physical properties and high dip angle of the reservoir,this paper uses the control variable method and grouping analogy method to study reservoir stimulation and energy supplement by combining indoor feasibility study with field practices.The results show that compared with the effects of nonfracturing,conventional fracturing,conventional stratified fracturing and hydraulic fracturing with large volume of fracturing fluid,the effect of clustering network fracturing is pretty good,and large displacement fracturing with low sand concentration in vertical wells can be used to further improve oil production at the initial production stage.Near miscible gravity drainage technology with gas injected into reservoir top can improve recovery factor by 6% comparing with waterflooding,which can be used as a most effective energy supplement way in the study area.Efficient development of low quality reserves in the area can be realized by applying clustering network fracturing to improve oil production at the initial production stage and by using gas-injection near-miscible gravity drainage to effectively control the production decline.