Abstract:

The downhole dynamic data acquisition for shale gas production mainly adopts such means as production logging or well testing with pressure gauge running by steel wire, which is with many shortcomings, for instance, much more wellhead equipment, complicated process, not timely acquisition of downhole data and short monitoring time. Therefore, a dynamic downhole wireless monitoring system for shale gas production has been developed. The system uses a technical architecture of wireless downhole data acquisition plus Wellhead Iot terminal and base data center to deliver wireless downhole data acquisition tools with tubing to the reservoir to collect such production dynamic data as wellbore fluid temperature, pressure, flow rate and water cut. The gathered data can be directly uploaded to the surface through electromagnetic wave transmitter, and then transmitted to the monitoring center of the base by the wellhead Internet of things after receiving by the ground antenna, realizing remote real-time observation of shale gas well performance from the center base, so that the wellhead production schedule can be adjusted according to the production requirements and further to improve well productivity. The system is suitable for 3500m well depth. When the amount of data is set to 4 groups per day (adjustable), the working time can reach 2 to 3 years. The system has been field trailed in Well Wei 204H36-6 and Well Wei 202H22-7 with accurately and timely obtained the dynamic production data. According to the monitoring data, Well 204H36-6 has been performed pressure control and production adjustment, which significantly slowed down the rate of formation energy attenuation and increased the oil recovery by 2% to 3%, Well 202H22-7 has given a timely alarm when the fracturing fluid from the adjacent well entered the wellbore, preventing the gas well from drowning by fracturing fluid. The development of downhole wireless monitoring system for shale gas well production has realized the long-term real-time monitoring for shale gas well during the production stage and with a good application effect, showing a great prospect of popularization and application.

Key words: shale gas well; downhole; production performance; real-time monitoring, wireless transmission

摘要： 目前页岩气生产过程中井下动态资料的获取途径主要采用生产测井或钢丝下压力计试井等方式，其存在井口装备多、工序复杂、井下数据获取不及时、监测覆盖时间短等不足，为此，开发了一套页岩气井生产动态井下无线监测系统。该系统采用“井下数据无线采集”+“井口物联网终端”+“基地数据中心”的技术架构，将井下数据无线采集工具随油管一起送到储层中，采集井筒中流体温度、压力、流量及含水率等生产动态数据，并直接通过电磁波发射器上传到地面，地面天线接收后再由井口物联网传输到基地监测中心，实现在基地即可远程实时观察页岩气井的井下生产动态情况，根据生产需要及时调整井口生产制度，以便提升生产井的产能。本系统适用井深3 500m左右；在设定数据量为4组/d（可调）时，工作时长可达2～3年。系统在威204H36-6井及威202H22-7井进行了现场应用，获取的生产动态数据准确、及时。其中，威204H36-6井根据监控数据开展了控压调产，明显减缓了地层能量衰减速度，提高采收率2~3%；威202H22-7井在邻井的压裂液进入井筒时进行了及时的报警，防止了气井被压裂液淹死情况的发生。页岩气井生产动态井下无线监测系统的开发实现了页岩气井在生产阶段的长期实时监测功能，应用效果良好，具有推广应用的良好前景。

关键词: 页岩气井, 井下, 生产动态, 实时监测, 无线传输