瓜胶压裂液体系示踪剂的筛选  

Selection of Tracers Used in Guar Gum Fracturing Fluid

作　　者：池晓明 李旭航[2] 张世虎[3] 马晓鹏[2] 

机构地区：[1]中国石油川庆钻探工程有限公司长庆井下技术作业公司 [2]西安石油大学石油工程学院 [3]中国石油长庆油田分公司第三采气厂

出　　处：《钻井液与完井液》2015年第5期83-85,107,共3页Drilling Fluid & Completion Fluid

基　　金：西安石油大学博士科研启动基金项目(2014BS34)

摘　　要：在油气田开发过程中,多数油气井压裂通常是采取分段压裂,各层段一起合排,此过程目前常用总的返排量来判断整体压裂液的返排效果,而无法了解各个层段压裂液的返排情况。为了评价各层段压裂液的返排效果,可在各层段压裂过程中加入一定浓度的不同示踪剂,在返排时对压裂液返排液进行连续取样,检测返排液中各种示踪剂的浓度,从而判断各层段的返排效果,计算压裂液在地层中的残留量。而在压裂中所用示踪剂需要与压裂液配伍,对油田常用的几种示踪剂进行了实验评价。实验研究结果表明,小分子醇类和无机阴离子(SCN-和Br-)不适合作为瓜胶压裂液示踪剂,2种微量物质TA和TB与瓜胶压裂液配伍,不会对压裂液成胶和破胶产生影响,并且由于其在地层环境中有较低的吸附量,不会对定量测量造成影响,可初步选为压裂液示踪剂。In oil and gas development, most often the reservoirs are fractured in staged fracturing manner, and all the fracturing fluids entering into each zone are flowed back together to the surface. This process can be used to assess the backflow of the fracturing fluid as a whole, and is incapable of assessing the backflow of fracturing fluid form each single zone. To assess the backflow of the fracturing fluid from each single zone, tracers are added to the fracturing fluid into each zone at certain concentrations. Then the backflow is sampled continuously to detect the concentration of tracers therein, and the efficiency of the backflow of each zone can thus be determined. Tracers used in this process should be compatible with the fracturing fluid. In a series of laboratory experiments, low molecular weight alcohols and inorganic ions is proved not suitable for use as tracers in guar gum fracturing fluids, two other substances, TA and TB, on the contrary, are compatible with the guar gum, and have low adsorption in most reservoir environments(indicating that their use will notaffect the concentration measurement at the surface.), and are suitable for use as tracers in guar gum fracturing fluid.

关 键 词：瓜胶压裂液 示踪剂 返排效果 低渗透储层 分段压裂 

分 类 号：TE357.12[石油与天然气工程—油气田开发工程]