| Autor: |
CHENG Qiuyang, YANG Hongzhi, YOU Lijun, KANG Yili, CHANG Cheng, XIE Weiyang, JIA Na, TANG Xuefeng |
| Jazyk: |
čínština |
| Rok vydání: |
2024 |
| Předmět: |
|
| Zdroj: |
Youqi dizhi yu caishoulu, Vol 31, Iss 6, Pp 96-108 (2024) |
| Druh dokumentu: |
article |
| ISSN: |
1009-9603 |
| DOI: |
10.13673/j.pgre.202308031&lang=en |
| Popis: |
Horizontal well multi-stage hydraulic fracturing technology makes the development of shale gas reservoirs efficient. However， water-rock interaction between shale rock and the work fluids like water-base drilling fluid， alkaline oil-base drilling fluid， slick-water fracturing fluid， pre-acid fluid， and oxidizing rubber breaking fluid may potentially affect wellbore stability， fracturing stimulation effect， shut-in performance， and flowback efficiency during the drilling process. This paper discusses the significance of water-rock interaction on shale gas development by systematically summarizing the mechanism of water-rock interaction and the response characteristics of shale pore structure under water-rock interaction in shale gas reservoirs in China and abroad. Shale is found rich in water-sensitive components such as clay minerals， acid-sensitive components such as carbonate minerals， alkali-sensitive components such as quartz， and oxidative-sensitive components such as organic matter and pyrite. The hydrolysis of shale components is very poor， while hydration swells and associated fracture generation due to clay minerals are prominent. The distribution of pores and fractures in shale is closely related to the chemically unstable components of quartz， carbonate minerals， organic matter， and clay minerals. Chemical dissolutions include acidizing， alkali， and oxidative dissolutions. The dissolution of shale components under water-rock action induces the dissolution and enlargement of pores and fractures， which also impairs the mechanical properties of rock. It is pointed out that optimizing working fluid， like the application of oxidative-acid and oxidative fracturing fluid， is conducive to improving the fracturing stimulation effect， promoting adsorption gas production， and improving shale gas recovery. Meanwhile， determining the maximum shut-in time based on the inflection point of the pressure drop curve and constructing the pressure control production system considering the protection of the diversion capacity of the fracture network can guide the reasonable pressure control in the whole process of gas well production， extend the stable production period， and increase the production of a single well. |
| Databáze: |
Directory of Open Access Journals |
| Externí odkaz: |
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