氮气循环钻井开环现场试验

Open loop field test of nitrogen circulation drilling system

李军 柳贡慧 王锡洲

LI Jun LIU Gonghui WANG Xizhou

中国石油大学石油天然气工程学院，北京　102249 北京联合大学，北京　100101 中国石油化工股份有限公司科技发展部，北京　100728

Faculty of Petroleum Engineering, China University of Petroleum, Beijing 102249, China Beijing Union University, Beijing 100101, China China Petroleum &

为降低气体钻井成本，提高钻井技术水平，对氮气循环钻井新工艺首次进行了开环现场试验，即气体分离处理后再行排放，以考察分离过滤设备的工作性能以及分离过滤设备对钻井工艺的适应能力。为保证试验的顺利进行，设计了气密性试验、正常钻进过程试验、地层出水过程试验等。试验结果表明，该工艺简单易行，系统运行稳定可靠。分离后的气体介质所含固相颗粒粒径与浓度低于当地大气条件，可满足重新进入压缩机和增压机的要求，为实现氮气的再次注入井内循环利用创造了有利条件。根据现场试验暴露出来的问题，进行了具体分析并提出了改进方案。该系统完善后，可以在气体钻井中推广应用。

The open loop field test of the new nitrogen circulation drilling system has been done for the first time to decrease nitrigen drilling cost and update drilling technology, that is, nitrogen is discharged after separating process, as a result the performance of separting and filtering equipment and its applicability of to drilling technology could be examined. In order to assure successful test, air tight test, regular drilling process test, and formation water production process test are designed. The result shows that the new technology is easy to handle and the whole system is credible. Particle size and content of the drilling cuttings in nitrogen after separation are all less than that of the local atmosphere, which is suitable to be injected into the compressor and booster again. This is helpful for the cyclic utilization of the costly nitrogen. Based on the analysis of problems during field test, some improved solutions are put forward. The new nitrogen circulation drilling system can be used widely after further improvement.