Supramolecular fracturing fluid system for imbibition oil recovery and application of supramolecular fracturing fluid system for imbibition oil recovery

Abstract

The invention discloses a supramolecular fracturing fluid system for imbibition oil recovery and application of the supramolecular fracturing fluid system for imbibition oil recovery. The supramolecular fracturing fluid system for imbibition oil recovery is composed of the following components in percentage by weight: 0.2-0.7% of a supramolecular fracturing fluid thickener, 0.05-0.6% of a double-effect agent, 0.05-2% of a clay stabilizer, 0.05-0.4% of an efficient gel breaker and the balance water. The produced supramolecular fracturing fluid system for imbibition oil recovery is used for imbibition oil recovery work of a low-permeability tight oil reservoir, not only can the produced supramolecular fracturing fluid system for imbibition oil recovery be used as fracturing fluid for fracture forming and sand carrying, but also gel breaking liquid of the produced supramolecular fracturing fluid system for imbibition oil recovery can be used as imbibition liquid for changing the wettability of a reservoir matrix and reducing oil-water interfacial tension, and when imbibition oil recovery is conducted on the reservoir, through a method of combining fracturing and imbibition, not only is the imbibition recovery efficiency of the low-permeability tight oil reservoir improved, but also the problems that fracturing flow-back fluid is hard to treat, the recycling rate is low, and resources are wasted are solved.

Description

technical field [0001] The invention relates to a supramolecular fracturing fluid system for imbibition oil recovery and its application, and belongs to the technical field of oil and gas field imbibition oil recovery development. Background technique [0002] In recent years, due to the increasing demand for oil and gas resources worldwide, low-permeability tight oil and gas resources have become an indispensable and important part of the global energy structure, and their status has become increasingly prominent. my country's low-permeability reservoirs are very rich in resources, ultra-low permeability (class II 1-10md, class III 0.1-1md) accounts for more than 58%, and there are more than 300 oil fields. However, the development of low-permeability reservoirs is very difficult, and the general recovery level is 5-28%, with an average level of 13.6%. Compared with conventional reservoirs, the common problems in the development of low-permeability tight oil reservoirs are...

AI Technical Summary

Problems solved by technology

However, the development of low-permeability reservoirs is very difficult, and the general recovery level is 5-28%, with an average level of 13.6%.

Compared with conventional reservoirs, the common problems in the development of low-permeability tight oil reservoirs are low formation pressure, low energy, low porosity, low permeability, and strong heterogeneity. Effect

In addition, conventional fracturing fluids have traditional guar gum with high friction resistance and many residues; large amount of VES, high cost and poor temperature resistance; chemical cross-linked polymer system, difficult to control the cross-linking process, temperature resistance and shear resistance Issues waiting to be improved

At the same time, the fracturing flowback fluid is difficult to handle, the recycling rate is low, and resources are wasted

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