Multistage dynamic temporary blocking volume acid fracturing method

Abstract

The invention discloses a multistage dynamic temporary blocking volume acid fracturing method. According to the multistage dynamic temporary blocking volume acid fracturing method,"multistage physical temporary blocking" and "multistage chemical temporary blocking" are treated as principle thinking, and multistage hydraulic fracturing with sand and multistage injection acid fracturing are combined. According to pump injection sequence of front-loading linear glue with certain concentration to make seams, saturating a reservoir, improving flow conductivity of fractures by propping agents with the small grain size or composite grain size, and injecting degradable acid-resistant fiber temporary blocking fluid, through multistage with large displacement, the fracture physical steering transformation is achieved; and then through a multistage interval type with large displacement, different types of acid liquors "mutual solvent, gelled acid, steering acid..., mutual agent" are injected, and thus fracture chemical temporary blocking steering transformation is achieved. According to the multistage dynamic temporary blocking volume acid fracturing method,the pertinence and the flow conductivity of the reservoir are improved, the loss of the acid liquors are lowered, the etching length of the fractures are increased, the transforming volume of the reservoir is enlarged by fracture steering, and thus the target that the individual well producing rate is improved by effective transformation of the cloud-like carbonate rock reservoir is achieved.

Description

technical field [0001] The invention belongs to the field of reservoir reconstruction, in particular to a multi-stage dynamic temporary plugging volumetric acid fracturing method. Background technique [0002] For the Lower Paleozoic carbonate reservoirs in Changqing Oilfield, conventional acid fracturing, multi-stage injection acid fracturing, closed acid fracturing, pre-fluid acid fracturing and other technologies have been tested successively, and certain effects have been achieved. The length of the fracture is short, and the gas supply capacity of the reservoir matrix to the fracture is poor. It is difficult to achieve the expected production stimulation effect only by a single fracturing main fracture. The overall stimulation effect of acid fracturing is poor, and the production decline after fracturing is rapid. In order to increase the single well production of Lower Paleozoic carbonate reservoirs, and to solve or slow down the conventional acid fracturing technology...

AI Technical Summary

Problems solved by technology

[0002] For the Lower Paleozoic carbonate reservoirs in Changqing Oilfield, conventional acid fracturing, multi-stage injection acid fracturing, closed acid fracturing, and pre-fluid acid fracturing have been tested successively, and certain effects have been achieved. The length of the fracture is relatively short, and the gas supply capacity of the reservoir matrix to the fracture is poor. It is difficult to achieve the expected production stimulation effect only by a single fracturing main fracture. The overall stimulation effect of acid fracturing is poor, and the production declines rapidly after fracturing

In order to increase the single well production of Lower Paleozoic carbonate reservoirs, and to solve or slow down the conventional acid fracturing technology, the acid-rock reaction rate is fast, the acid fluid leakage is large, the extension of acid-etched fractures is limited, and the stimulation volume is limited. , Insufficient diversion capacity, uneven and insufficient stimulation of heterogeneous reservoirs, etc.