A Method for Evaluation of Polymer Injection Capability in Low Permeability Reservoirs

Abstract

The invention provides a method for evaluating the polymer injection capacity of low-permeability reservoirs. By carrying out physical simulation experiments of polymer injection properties under different reservoir conditions, the plugging capacity, polymer injection pressure, resistance coefficient, residual resistance coefficient, and viscosity are obtained. 6 parameters of retention rate and injection curve characteristics, and further use the gray correlation coefficient method to calculate the impact factor of each parameter, determine the weight of each parameter, and determine the score of each parameter for each category, and then determine the polymer injectability Evaluation standard, simple and effective quantitative evaluation of polymer injection ability, and according to this standard, polymers with good viscosification, good shear resistance, good injectability and good stability under oil layer conditions are selected, which are suitable for reservoir conditions, so that Improve the oil displacement effect of polymer flooding and binary flooding.

Description

A method for evaluating polymer injectability in low-permeability reservoirs technical field The invention belongs to the technical field of oilfield exploitation, be specifically related to a kind of low permeability oil reservoir polymer injection ability evaluation method Law. Background technique With the prolongation of water flooding time, the oil field gradually enters the medium and high water cut development stage, especially for the horizontal and vertical non- For reservoirs with severe homogeneity, polymer flooding can change the oil-water mobility ratio, expand the swept volume, and improve the oil displacement efficiency. polymer flooding As the main tertiary oil recovery process for oilfield development or production increase, it has been widely used at home and abroad. It reaches 80‑150 tons, which is 6%‑12% higher than water flooding recovery. The effectiveness of polymer flooding depends on many factors, among which A very important factor is th...

AI Technical Summary

Problems solved by technology

This application involves a method for evaluating the injection capacity of multi-reservoir polymer injection wells considering the viscoelasticity of polymers. It mainly solves the injection capacity by establishing a polymer seepage mathematical model, and does not consider how to evaluate the polymer injection capacity under real reservoir conditions.

Images