摘要
对比页岩气藏,致密气藏受地质结构、含水饱和度、赋存状态等因素影响,在开采机理上存在较大差异,压裂工艺、压裂液成分、配比等有所不同,导致返排液的返排比例和物质组成存在差异。本文针对返排液构成复杂的特点,以四川盆地致密气压裂返排液为研究对象,通过与页岩气指标进行对比分析,明确了区块内压裂返排液水质主要特征:致密气区块返排液中BOD5、COD、TOC三类表征有机物含量的指标均高于页岩气井,且石油类是造成有机物指标含量高的主要原因;无机物指标中总钙、总硬度指标高于页岩气井,总矿化度(TDS)、氯化物、总钡、总硼、总钾、总钠等指标低于页岩气井。本研究结果可为该区块致密气开采过程压裂返排液污染物控制措施及处理技术的选择提供参考。
Compared with shale gas reservoirs,tight gas reservoirs are affected by geological structure,water saturation,occurrence state and other factors,so there are great differences in production mechanism,fracturing technology,fracturing fluid composition and ratio,which lead to differences in flowback proportion and material composition of flowback fluid.In view of the complex composition of flowback fluid.This paper takes tight gas fracturing flowback fluid in Sichuan Basin as the research object,and through comparative analysis with shale gas indicators,identifies the main water quality characteristics of fracturing flowback fluid in the block:BOD5,COD and TOC in the flowback fluid of tight gas block are higher than those of shale gas Wells,and petroleum is the main reason for the high content of organic matter index.Among the inorganic indexes,the total calcium and total hardness indexes were higher than those in shale gas Wells,while the total salinity(TDS),chloride,barium,boron,potassium and sodium indexes were lower than those in shale gas Wells.The results of this study can provide a reference for the selection of control measures and treatment technologies for the pollutants in fracturing flowback fluid during tight gas production in this block.
作者
王越
杨杰
陈天欣
唐全武
王兴睿
Wang Yue;Yang Jie;Chen Tianxin;Tang Quanwu;Wang Xingrui(Research Institute of Safety,Environmental Protection and Technical Supervision,PetroChina Southwest Oil&Gasfield Company,Chengdu 610041;Sichuan Key Laboratory for Shale Gas Evaluation and Exploitation,Chengdu 610041,China)
出处
《广东化工》
CAS
2023年第10期153-155,167,共4页
Guangdong Chemical Industry
关键词
致密气
页岩气
压裂返排液
水质特征
污染物
tight gas
shale gas
fracturing flowback fluid
water quality characteristics
contaminants
