ACID TREATMENT FLUID FOR DELAYED ACIDIFICATION IN PETROLEUM INDUSTRY Russian patent published in 2023 - IPC E21B43/27 C09K8/52 C09K8/74 

FIELD: development of underground geological formations.

SUBSTANCE: in a method of developing a subterranean geological formation by introducing an acidizing fluid containing a monochloroacetic acid monosalt into the subterranean geological formation in presence of at least one bromide or iodide salt or a salt precursor, the monochloroacetic acid monosalt is present in the acidizing fluid at an amount ranging from 3 to 20% by weight based on the total weight of the acidizing fluid. At least one bromide or iodide salt or salt precursor is introduced into the subterranean geological formation in an amount ranging from 0.3 to 10 wt.% based on the total weight of the acidizing fluid. At least one bromide or iodide salt or salt precursor is present in the acidizing fluid introduced into the subterranean geological formation, or at least one bromide or iodide salt or salt precursor is introduced into the subterranean geological formation prior to introduction of the acidizing fluid.

EFFECT: deeper penetration of the acidizing fluid into subterranean formations, depleting the acidizing fluid in the subterranean formation before pumping it back to a level above ground level.

15 cl, 1 dwg, 4 tbl, 3 ex