Method for determining corrosion rate of natural gas injection and production well pipe column under erosion-carbon dioxide corrosion coupling action

Abstract

The invention belongs to the technical field of oil field equipment and particularly provides a method for determining a corrosion rate of a natural gas injection and production well pipe column under an erosion-carbon dioxide corrosion coupling action. The method comprises the steps of 1) establishing a pipe column internal component heat transfer, flow and dispersion model; 2) establishing a pipe column wall surface carbon dioxide corrosion model and determining influence of a product layer on the corrosion rate in a carbon dioxide corrosion process; 3) establishing a model of wear of medium erosion on a pipe wall substrate and a corrosion layer; and 4) coupling the three models and determining the corrosion rate of the natural gas injection and production well pipe column. According to the method, a gas well pipe column corrosion rate prediction model is established through an erosion-electrochemical corrosion coupling action mechanism in the natural gas injection and production well pipe column, so that the corrosion rate of the natural gas injection and production well pipe column can be effectively predicted and a technical reference is provided for the security of the natural gas injection and production well pipe column carrying carbon dioxide and liquid water.

Description

technical field [0001] The invention belongs to the technical field of oilfield equipment, and relates to a method for evaluating the safety service of a vertical pipe string of a natural gas well, in particular to a method for determining the corrosion rate of a pipe string of a natural gas injection-production well under the coupled action of erosion-carbon dioxide corrosion. Background technique [0002] With the growth of my country's demand for clean energy, the extraction of natural gas continues to increase. However, during the extraction of natural gas, most of the blocks contain CO 2 、H 2 O and other corrosive media enter the gathering, transportation and storage system, which not only affects the service life of natural gas collection and transportation pipes and processing equipment, causes large economic losses to the oil and gas industry, but also causes great pollution to the environment. With the development of natural gas year by year, the depth of the rese...

AI Technical Summary

Problems solved by technology

[0005] Most of the existing erosion models focus on the erosion research of gas-solid / liquid-solid two-phase flow, which mathematically describes the erosion rate of metal materials with the changes in target properties, particle properties, and environmental factors. Starting with the collision process of the impact target, by solving the particle motion equation and the energy equation of the collision, a plastic material erosion model based on micro-cutting and deformation wear is established. There are few discussions on the electrochemical corrosion process, and it is not suitable for sand-free Liquid-carrying sour natural gas well string environment

Images