Clean steering acid liquid system for acidification and preparation method thereof

Abstract

The invention discloses a clean steering acid liquid system for acidification and a preparation method thereof. The clean steering acid liquid system comprises a solution A and a solution B, wherein the solution A comprises the following raw materials in parts by weight: 32-71 parts of 31% hydrochloric acid solution, 0.5-2.0 parts of ferric ion stabilizer, 0.5-2.0 parts of corrosion inhibitor, 1.0-2.0 parts of surfactant, 3.0-4.0 parts of clay stabilizer, and 19-63 parts of water; the solution B comprises the following raw materials in parts by weight: 8-15 parts of mutual solvent and 85-92 parts of water. The preparation method comprises the following steps: adding the surfactant to a container containing water; evenly agitating, and then adding the clay stabilizer, the corrosion inhibitor and the ferric ion stabilizer; finally adding the hydrochloric acid solution, so as to prepare the solution A; and adding the mutual solvent to the container containing water, so as to prepare the solution B for gel breaking of the clean steering acid liquid system. By adopting the acid liquid system disclosed by the invention, the formula is simple in component, good in steering effect, and free of damage to a reservoir, and controls the self-steering function.

Description

technical field [0001] The invention relates to the field of petroleum exploitation, in particular to a clean diverting acid liquid system and a preparation method thereof. Background technique [0002] The diverting acid acidizing systems developed earlier are all polymer systems, which have two major disadvantages: First, due to incomplete gel breaking, viscous fluid stays in the formation and fractures, resulting in difficult flowback, and the flowback rate is generally low , only about 35%-65%; the second is that the polymer system forms a filter cake in the formation, which blocks the pore space of the formation and supporting fractures, and reduces the permeability of the reservoir and the conductivity of the fractures. In addition, the system also has limitations such as poor steering effect and complicated process, making it difficult to achieve the expected transformation goals. [0003] The clean steering acid developed in recent years is a new polymer-free acid s...

AI Technical Summary

Problems solved by technology

[0002] The diverting acid acidizing systems developed earlier are all polymer systems, which have two major disadvantages: First, due to incomplete gel breaking, viscous fluid stays in the formation and fractures, resulting in difficult flowback, and the flowback rate is generally low , only about 35%-65%; the second is that the polymer system forms a filter cake in the formation, which blocks the pore space of the formation and supporting fractures, and reduces the permeability of the reservoir and the conductivity of the fractures

[0004] In the process of realizing the present invention, the inventors have found that the prior art has at least the following problems: there is no complete solution for the acidification technology of the diverting acid in the prior art; The formation damage is greater