苏里格气田南区下古生界气藏流动单元量化与控水开发对策

The quantification of flow unit and the preparation of water-control development strategy for Lower Palaeozoic gas reservoir in the southern area of Sulige Gas Field

苏里格气田南区下古生界气藏(简称苏南下古气藏)是苏里格气田一个典型的水侵活跃型气藏,产气贡献突出的同时,产水却严重影响了气井产能。为了实现有效分类管理该区块,开展了流动单元的研究。以流动层指数(FZI)为桥梁,成功实现了流动单元的量化,在地质单元认识的基础上,进一步细化了流动单元,将苏南下古气藏划分为三类流动单元。不同类别的流动单元,其生产特征各异,为了确定相应的控水生产对策,利用数值模拟的手段,考虑边水和底水两种模型,预测气井在不同配产下的产气产水情况。模拟结果表明,目前气井配产过高,导致产水日趋严重,为了达到控水稳产的效果必须降产。在此基础上,针对不同流动单元的高产水气井,选取9口典型井开展了不同生产制度下的控水生产现场试验,根据试验效果制定了相应高产水气井的控水生产对策,并推广应用于苏南下古气藏,取得了显著效果,为实现气藏的高效开发提供了有力的技术支撑。

The Lower Paleozoic gas reservoir in the southern area of Sulige Gas Field （hereinafter the Sunan Lower Paleozoic gas reservoir for short） is a typical gas reservoir with active water invasion in Sulige Gas Field. It makes great contribution to the gas production, but in the meantime, the productivity of gas wells is impacted seriously by the water production. To realize effective clas- sification management in this block, flow units were studied in this paper. The flow units were successfully quantified with the flow zone index （FZI） as the bridge. After the geologic units were recognized, the flow units were divided further, and the Sunan Lower Paleozoic gas reservoir was divided into three types of flow units, whose production characteristics are different. To prepare the water control production strategies correspondingly, the gas and water production rates of gas wells with different prorations were predicted by means of numerical simulation based on two models of edge water and bottom water. It is indicated that the water production is more and more serious gradually as the current proration of gas wells is too high. To realize water control and production stabiliza- tion, therefore, the proration has to be decreased. Then, 9 typical wells were selected from the gas wells with high water production in different flow units to conduct field tests on water control production in different production systems. And according to the test re- sults, the control water production strategies were prepared corresponding to the gas wells with high water production, and then were popularized to the Sunan Lower Paleozoic gas reservoir. And the application results are remarkable. It provides the powerful technical support for the efficient development of gas reservoirs.