Reusable modified guar gum fracturing fluid system

Abstract

The invention relates to a reusable modified guar gum fracturing fluid system. According to the technical scheme, the system comprises a primary mixed solution and a secondary mixed solution, wherein chemicals of a reusable fracturing system are adopted as the primary mixed solution and include compound modified guar gum, an organo-boron cross-linking agent, a low-temperature activator, a cleanup activator, a gel breaker removal adhesion preserving agent, an ionic equilibrium regulator, a molecular remodeling carding agent and a gel breaker. The base fluid formula of the secondary mixed solution includes an antibacterial agent formaldehyde, a gel breaker removal adhesion preserving agent, an ionic equilibrium regulator, thickening agent guar gum and a cleanup activator. The system has the advantages that the problems about water lack and environmental protection pressure during oilfield development in dry and rainless regions are solved, and secondary utilization of flowback fluid of fracturing fluid is achieved. On the premise that the requirements for safe fracturing construction and reservoir protection are met, fracturing fluid is easy to maintain and process and can be repeatedly used, the treatment amount of the flowback fluid is reduced, and water resources are saved.

Description

technical field [0001] The invention relates to a fracturing fluid recycling technology for oil field production, in particular to a reusable modified guar gum fracturing fluid system. Background technique [0002] With the accelerated pace of development in western China, the development of oil and gas fields in western China has also entered the stage of large-scale development. The benefits brought by the large-scale development are in stark contrast to the fragile environment in the west. In addition, there is drought and little rain in western China, and water resources are in short supply. The mountainous terrain severely restricts the further development of oil and gas fields. [0003] Taking the Weibei Oilfield of Sinopec North China Bureau as an example, the Weibei Oilfield block is located on the Loess Plateau in northern Shaanxi, with an altitude difference of 300m, an annual average temperature of 8.9°C, and an annual average precipitation of 709.3mm. Resources ...

AI Technical Summary

Problems solved by technology

[0007] At present, domestic oilfields mainly use conventional water-based hydroxypropyl guar gum fracturing fluid system. Due to the influence of molecular structure, cross-linking and gel-breaking methods, the useful components in the gel-breaking flowback fluid after fracturing operations are not easy to retain and reuse. Difficult to process and recycle

[0008] 2. The reuse level of flowback liquid is low

[0010] 3. Low recycling rate of flowback liquid

[0012] At present, domestic fracturing has become a key link in the exploration and development of low-permeability oil and gas reservoirs. The number of wells and the scale have increased year by year, and the amount of fracturing fluid and flowback fluid has also increased. The waste of water resources and environmental pollution have attracted much attention. Traditional flowback Fluid treatment technology can no longer meet the needs of green development, so the research on fracturing fluid reuse technology has been paid more attention, which has become the development trend of social development and fracturing technology progress

[0013] So far, based on the analysis of the status quo of fracturing fluid reuse research at home and abroad, no mature fracturing flowback fluid recycling technology has been formed. Carrying out research on fracturing fluid reuse is a demand for industry progress and development