天然气工业2024，Vol.44Issue(2)：92-98,7.DOI:10.3787/j.issn.1000-0976.2024.02.009
基于压裂液自发吸入模型的页岩气压裂液滤失定量预测
Quantitative prediction of fracturing fluid leak-off in shale gas reservoirs based on spontaneous imbibition model of fracturing fluid
王琳琳 1蔺小博 2冷静怡 3周长静 2马占国 2肖元相2
作者信息
- 1. 中国石油大学(北京)安全与海洋工程学院
- 2. 中国石油长庆油田公司油气工艺研究院
- 3. 巴黎高科路桥学院
- 折叠
摘要
Abstract
Hydraulic fracturing is often used for the development of unconventional oil and gas resources to improve the production rate of single well.However,the field data of fracturing indicate that a large amount of fracturing fluid retains in the strata,which results in a lower flowback rate of fracturing fluid and may have some impact on underground reservoirs and groundwater environments.In order to further study the leak-off mechanism of fracturing fluid and accurately predict the amount of fracturing fluid leak-off,this paper establishes a model describing the spontaneous imbibition of fracturing fluid caused by capillary force.Then,the amount of fracturing fluid leak-off is quantitatively calculated,and verified using the field data.Finally,the dimensionless imbibition rate parameter is introduced to analyze the key factors controlling fracturing fluid loss.And the following research results are obtained.First,during the fracturing construction of a horizontal well in shale gas reservoirs,about 50%-95%of the fracturing fluid is imbibed through the matrix.The amount of imbibed fracturing fluid is only related to imbibition rate parameters,fracture areas and imbibition time.Second,when the ratio of wetted phase viscosity to non-wetted phase viscosity exceeds the threshold,the imbibition rate parameter is mainly dependent on the pore size distribution parameter of the rock,while the effect of fluid viscosity is very limited.Third,when the pore size distribution parameter is between 0.5 and 0.7,imbibition rate parameter reaches a higher value,i.e.,more fracturing fluid is imbibed into the strata.Fourth,when the ratio of wetted phase viscosity to non-wetted phase viscosity exceeds 10 and the pore size distribution parameter is less than 0.8,the optimized spontaneous imbibition model has greater applicability.In conclusion,the spontaneous imbibition model of fracturing fluid established in this paper can accurately predict the amount of fracturing fluid leak-off,and provides a technical support for the production of unconventional oil and gas and the environmental protection.关键词
页岩气藏/毛细管力/滤失/自发吸入/吸入率参数/流体黏度/孔径分布参数Key words
Shale gas reservoir/Capillary force/Leak-off/Spontaneous imbibition/Imbibition rate parameter/Fluid viscosity/Pore size distribution parameter引用本文复制引用
王琳琳,蔺小博,冷静怡,周长静,马占国,肖元相..基于压裂液自发吸入模型的页岩气压裂液滤失定量预测[J].天然气工业,2024,44(2):92-98,7.
