昭通太阳区块浅层页岩气水平井试气返排规律  

Gas Testing Flowback Rules of Shallow Shale Gas Horizontal Wells in TY Block of Zhaotong

作　　者：黄小青 韩永胜 杨庆 周芸 袁晓俊 刘晔 HUANG Xiaoqing;HAN Yongshen;YANG Qing;ZHOU Yun;YUAN Xiaojun;LIU Ye(Research Institute of Exploration and Development,Zhejiang Oilfield Company,PetroChina,Hangzhou,Zhejiang 310023,China)

机构地区：[1]中国石油浙江油田分公司勘探开发研究院,杭州310023

出　　处：《新疆石油地质》2020年第4期457-463,470,共8页Xinjiang Petroleum Geology

基　　金：国家科技重大专项(2017ZX05063005,2016ZX05037003)。

摘　　要：针对川南昭通国家级页岩气示范区太阳区块浅层页岩气藏埋藏浅、地层能量低和返排率高的特点,准确掌握浅层页岩气水平井试气返排规律,制定针对性的试气制度,对提高单井采收率具有重要意义。为此,借鉴邻区中深层页岩气水平井试气返排规律,结合研究区已试气井排采规律,根据气液两相渗流理论和应力敏感分析方法将研究区水平井试气过程划分为6个阶段,总结出每个阶段的试气返排规律,并制定相应的排采制度。结果表明:以日产气量、日产水量和井口压力作为评价标准,选择最优焖井时间、油嘴直径和调整油嘴时机,可大大降低应力敏感带来的储集层伤害,充分释放单井产能,达到准确求取试气产能、提高单井采收率的目的,同时也为投产初期配产提供依据。在此基础上,建立了2套针对研究区浅层页岩气水平井试气返排标准图版,用以指导现场生产,取得了较好的应用效果。Aiming at the shallow burial,low formation energy and high flowback rate of the shale gas reservoirs in Taiyang block of Zhaotong National Shale Gas Demonstration Area in the southern Sichuan basin,it is of great significance to accurately master the laws of gas testing and flowback of horizontal wells in shallow shale gas reservoirs and to formulate a specific test system for improving single well recovery.For this reason,drawing lessons from the gas testing law of the horizontal wells in the middle and deep shale gas strata in the adjacent block,and combining with the knowledge and practical experience of the water drainage and gas production law of the tested wells in the study area,the paper divides the gas testing process in the horizontal wells in the study area into 6 stages,summarizes the laws of gas test and flowback and formulates the corresponding production system on the basis of gas‑liquid two‑phase percolation theory and stress sensitivity analysis methods.The results show that the optimum well soak time,choke diameter and choke adjusting timing can be determined by taking the key parameters including daily gas production,daily water production and wellhead pressure as evaluation criteria,which can greatly reduce reservoir damages caused by stress sensitivity.Then gas testing productivity can be obtained and well recovery can be improved as well.Based on which,2 sets of standard charts have been established for gas testing and flowback in horizontal wells in shallow shale gas reservoirs in the study area,and the actual application in field production has proved the good effect of the charts.

关 键 词：昭通 太阳区块 浅层页岩气 水平井 焖井时间 试气 返排规律 

分 类 号：TE357[石油与天然气工程—油气田开发工程]