Ground stress extending, renovating and yield-increasing method for oil-gas well

Abstract

The invention discloses a ground stress extending, renovating and yield-increasing method for an oil-gas well. The ground stress extending, renovating and yield-increasing method comprises the following steps: S1, performing a field small crack diagnosis test, wherein geo-mechanical properties of an oil deposit are tested, and the geo-mechanical properties comprise three-dimensional main stress, permeability, reservoir pressure and crack fluid efficiency of a reservoir; S2, controlling injecting pressure to be greater than the smallest main stress of the reservoir and smaller than cracking pressure, adopting a circular hydraulic injection and reflow way at an inlet position, and improving ground stress and pore pressure around the well; S3, changing wellhead injection displacement, adopting an injection and reflow way, generating hydraulic shake in the reservoir to increase a pore volume, expanding micro crack and improving a seepage environment around the well; S4, performing low-sand-ratio injection, carrying silt in a low sand ratio, and supporting a hydraulic renovating region near the well; and S5, braising in the well for several days. The method is simple in process, is relatively low in construction cost, is relatively low in field equipment requirement, and is suitable for a compact sandstone reservoir, a shale reservoir and a reservoir with natural cracks.

Description

technical field [0001] The invention relates to the technical field of oil and gas field development and production increase, in particular to a method for oil and gas well in-situ stress expansion, modification and production increase. Background technique [0002] At present, many oil fields at home and abroad have entered the middle and late stage of development, and it is becoming more and more difficult to increase production, and they are facing many difficulties. The development method of heavy oil reservoirs is generally thermal oil recovery, but due to the high viscosity of crude oil, conventional thermal recovery technology is difficult to effectively develop, the oil field is faced with the requirement of increasing and stabilizing production, which needs to be realized by expanding the production scale of the oil field, so that the development of heavy oil steam huff and puff Contradictions are gradually exposed; for example, typical problems such as high steam i...

AI Technical Summary

Problems solved by technology

The development method of heavy oil reservoirs is generally thermal oil recovery, but due to the high viscosity of crude oil, conventional thermal recovery technology is difficult to effectively develop, the oil field is faced with the requirement of increasing and stabilizing production, which needs to be realized by expanding the production scale of the oil field, so that the development of heavy oil steam huff and puff Contradictions are gradually exposed; for example, typical problems such as high steam injection pressure in heavy oil steam huff and puff wells and long warm-up period in SAGD wells seriously restrict the efficient development of heavy oil resources

Secondly, sandstone reservoirs and thin-layer oil and gas reservoirs with loose structure are often accompanied by plane heterogeneity, and oil well plugging reduces production-no production. Conventional acid fracturing methods have poor effectiveness, short validity period, and are easy to form on a slightly larger scale. Cracked water channeling, etc.

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