Glacial acetic acid crosslinked weighted fracturing fluid as well as preparation method and application thereof

Abstract

The invention provides a glacial acetic acid crosslinked weighted fracturing fluid as well as a preparation method and an application thereof. The weighted fracturing fluid is prepared from the following components in percent by weight (based on 100%): 15-28 wt% of glacial acetic acid, 1-70 wt% of potassium formate, 0.8-1.5 wt% of a polyacrylamide polymer, 0.2-0.8 wt% of an aldehyde crosslinking agent, 0.005-0.02 wt% of a polyamine crosslinking activator, 1-5 wt% of a high-temperature stabilizer, 0.5-2.0 wt% of a corrosion inhibitor, 0.5-2.0 wt% of an iron ion stabilizer, 0.01-0.1 wt% of ammonium persulfate and the balance water. According to the weighted fracturing fluid, the crosslinking agent, the crosslinking agent activator and the polyacrylamide polymer can be crosslinked quickly andefficiently in the presence of high concentration glacial acetic acid and potassium formate at normal temperature (25 DEG C) or at a lower temperature. In addition, a superhigh temperature glacial acetic acid crosslinked weighted fracturing fluid system is suitable for a deep high temperature carbonate reservoir.

Description

technical field [0001] The invention belongs to the technical field of oil and gas field transformation, and in particular relates to a cross-linked glacial acetic acid weighted fracturing fluid and its preparation method and application. Background technique [0002] As a conventional and effective oil and gas stimulation measure, acid fracturing is widely used in carbonate formations. On the one hand, the ordinary acid system has low viscosity, strong fluid loss, and fast acid-rock reaction speed, which makes it difficult to achieve the purpose of connecting fractured (cavity) reservoirs in the far well zone. On the other hand, the acid system has high friction resistance and acid fracturing The high construction pressure limits the depth of acid fracturing. At present, a series of acid fluid systems suitable for reservoir stimulation in carbonate formations have been developed, including temperature-controlled viscous acid, diverting acid, high-temperature gelling acid, ...

AI Technical Summary

Problems solved by technology

[0005] In general, the prior art has realized the ground crosslinking of the crosslinking agent and thickener under acidic conditions to a certain extent, but the acid used in the prior art is generally hydrochloric acid and the composition of the crosslinking agent is complex, mainly organic Metal cross-linking agents or organic complex kinases have the disadvantages of complex preparation process and high cost. On the other hand, there is no report on the research on the aggravation of cross-linked jelly acid systems.

Images