示踪剂技术在致密砂岩气藏压裂中的应用  

Application of tracer technology in fracturing for tight sandstone gas reservoir

作　　者：温守国 谢诗章 张海波 王跃宽 WEN Shouguo;XIE Shizhang;ZHANG Haibo;WANG Yuekuan(CNOOC EnerTech-Drilling&Production Co.,Tianjin 300452,China)

机构地区：[1]中海油能源发展股份有限公司工程技术分公司,天津300452

出　　处：《非常规油气》2023年第2期94-100,共7页Unconventional Oil & Gas

基　　金：海油发展科技重大专项“高含凝析油气藏储层伤害评价及增产技术可行性研究”(HFZDZX-GJ2020-01-06)。

摘　　要：为了了解临兴中区块致密砂岩气藏压裂液返排情况,分析压裂效果,开展了压裂示踪剂监测技术研究工作,并将其应用于该区块2口井压裂监测中。在A水平井9段压裂中注入9种有机微量示踪剂,在目标井B井2层暂堵分段压裂的5个段塞中加入不同示踪剂,通过取样测试示踪剂浓度并在返排阶段计算压裂液返排率。结果表明,A水平井各段压裂液返排率上升趋势与累计返排量上升趋势基本一致。12天返排基本结束后,第9段返排率为20.73%,第7段返排率为18.69%,第6段返排率为15.35%,其余各段返排率均小于10%,其中第1段、第2段和第3段返排率小于5%。该井总返排率为11.79%,第9段、第7段和第6段返排率高于总返排率,说明这几段是主要的返排贡献段。B井第1层前置液返排率为6.75%,第1层携砂液返排率为13.44%,暂堵剂返排率为13.71%;第2层前置液返排率为28.10%,第2层携砂液返排率为25.19%。此次施工B井并未单独进行暂时封堵,而是同时进行了2层压裂。以上成果认识,为压裂液返排提供了一种有效的监测手段。In order to understand the flow back of fracturing fluid in tight sandstone gas reservoir of Linxingzhong block and analyze the fracturing effect, the research work of frac turing tracer monitoring technology was carried out, and it was applied to the fracturing monitoring of two wells in this block. Nine kinds of organic trace tracers were injected into the fracturing of the nine stages of horizontal well A, and different tracers are added to the five segments in the temporary plugging staged fracturing of target well B, the tracer concentration is tested by sampling and the flow back rate of fracturing fluid is calculated in the flow back stage. The results showed that for horizontal well A, the increasing trend of fracturing fluid flow back rate in each stage was basically consistent with the increasing trend of accumulated flow back rate. After the 12 days flow back was basically completed, the flow back rate of stage 9 was 20.73%, the flow back rate of stage 7 was 18.69%, the flow back rate of stage 6 was 15.35%, and that of all other stages was less than 10%, among which the flowback rate of stage 1, stage 2 and stage 3 were less than 5%. The total flow back rate of the well was 11.79%.The flow back rate of stages 9, stage 7 and stage 6 were higher than total, which indicated that these stages were the main flow back contributing stages. For well B, the pad fluid of first layer had a flow back rate of 6.75%, and the proppant fluid of first layer had a flow back rate of 13.44%, while the temporary plugging agent had a flow back rate of 13.71%, the pad fluid of second layer had a flow back rate of 28.10%, and the proppant fluid of second layer had a flow back rate of 25.19%. The well B was not fractured separately with temporary plugging, instead, both layers were fractured at the same time. The above results provide an effective monitoring method for fracturing fluid flowback.

关 键 词：示踪剂 监测 致密砂岩 压裂 返排率 

分 类 号：TE357[石油与天然气工程—油气田开发工程]