Heterogeneous Reservoir Acidizing Modification Method

Abstract

The invention belongs to the technical field of reformation of oil-gas field production reservoirs and provides an acidizing reforming method of a heterogeneous reservoir in order to solve the technical problems of the prior art that acidizing fracturing construction has poor operating efficiency and reformation effect of heterogeneous reservoirs is poor. The method comprises the steps of A, performing cased well completion; B, performing fracture forming; C, injecting an acid; D, injecting a fracturing propping fluid, to be specific, filling excessively-acidized areas of all heterogeneous reservoirs with the fracturing propping fluid via shafts, repeating step C if continuously injecting the cleaning acid is required, and proceeding step E if not; E, injecting a displacing fluid, to be specific, using the displacing fluid to inject the liquid in the shafts into the heterogeneous reservoirs. Through the steps such as cased well completion, fracture forming, acid injecting, fracturing propping fluid injecting and displacing fluid injecting, acidizing reforming of a heterogeneous reservoir is effectively achieved, exploiting of the reservoirs is facilitated accordingly; the method has great economic benefit.

Description

technical field [0001] The invention belongs to the technical field of reservoir transformation for oil and gas field exploitation, and in particular relates to a heterogeneous reservoir acidification transformation method. Background technique [0002] The heterogeneity of the reservoir is mainly manifested in the heterogeneity of rock material composition and the heterogeneity of pore space. Due to the difference between sedimentation and diagenesis, the rock mineral composition, matrix content, and cement content are all different, which affects the change of pore shape and size and reservoir physical properties, forming heterogeneity in the reservoir layer, plane, and interlayer. qualitative. In waterflood development oilfield, reservoir permeability is an important factor affecting oilfield development. Permeability is commonly used to indicate the heterogeneity of a reservoir. Common representation methods include permeability gradient, variation coefficient, and he...

AI Technical Summary

Problems solved by technology

[0003] Due to the influence of randomness in the natural deposition process of the reservoir, there may be characteristics of large differences and strong heterogeneity

During the process of acidizing and fracturing, due to the difference in physical properties and lithology of different reservoirs, the amount of other reformed fluids such as acid liquid may enter into a large difference. Reservoirs with better physical properties and lithology are often easier to enter a large amount of reformed fluid. In order to make other Reservoirs with poor physical and lithological conditions can enter more stimulated fluids, and the isolation tool is usually run into the pipe. However, as the depth of the oil and gas well increases, the difficulty of running the tool increases greatly, and running the tool multiple times will consume a lot of work time

At present, packer segmental stimulation technology is usually used to stimulate multiple reservoirs with strong heterogeneity. This technology has a wide range of applications and is relatively mature. However, it is difficult to run in-line tools for deep well applications. Isolation takes a long time, which limits the efficiency of acid fracturing construction