集输管道CO$_2$腐蚀预测机理模型研究

A Study on Mechanistic Prediction Model of Gathering Pipelines in CO$_2$ Environment

蒋宏业 刘映雪 何莎 骆吉庆 徐涛龙

JIANGHongye LIUYingxue HESha LUOJiqing XUTaolong

西南石油大学石油与天然气工程学院, 四川 成都 610500 中国石油川庆钻探工程有限公司安全环保质量监督检测研究院, 四川 广汉 618300

Petroleum Engineering School, Southwest Petroleum University, Chengdu, Sichuan 610500, China Safety Environment and Quality Supervision and Inspection Research Institute of CNPC Chuanqing Drilling Engineering Co. Ltd., PetroChina, Guanghan, Sichuan 618300, China

CO$_2$驱油技术因能显著提高油藏采收率而在各大油田得到广泛应用，但采出液中CO$_2$含量的升高却使得地面集输管道腐蚀现象严重。针对地面集输管道CO$_2$腐蚀问题，开展了腐蚀产物膜影响下CO$_2$腐蚀速率预测研究。依据腐蚀热力学和腐蚀动力学理论，考虑流体流动、电化学反应、传质过程等多场耦合作用，在Nesic等研究的基础上引入腐蚀产物膜对离子传质扩散系数的影响因子，提出了新的腐蚀预测机理模型，并对化学、电化学及传质计算进行了改进。利用文献中实验数据对模型的预测结果进行了对比与验证，结果表明，腐蚀预测模型与实验数据吻合情况良好，在腐蚀产物膜存在的条件下能够实现腐蚀预测速率的有效修正，进一步提高了CO$_2$腐蚀预测机理模型的适用性和准确性，为油气生产和加工输送管道及相关设施设计提供一定参考。

CO$_2$ flooding technology has been widely used in major oil fields because of its ability to significantly improve reservoir recovery. However, the increase of CO$_2$ content in the produced fluid leads to serious corrosion of ground gathering and transportation pipelines. In order to solve the problem of CO$_2$ corrosion of ground gathering and transportation pipelines, the CO$_2$ corrosion rate prediction research under the influence of corrosion product film is carried out. Based on the corrosion thermodynamics and kinetics theory, considering the multifield coupling effects such as fluid flow, electrochemical reaction and mass transfer process, the influence factors of corrosion product film on the diffusion coefficient of ion mass transfer are introduced, and a new corrosion prediction mechanism model is proposed based on the work of Nesic et al, and the chemical, electrochemical and mass transfer calculations are improved. The prediction results of the model are compared and verified by using the experimental data in the literature. The results show that the corrosion prediction model is in good agreement with the experimental data. In the presence of corrosion product film, the corrosion prediction rate can be effectively revised, which further improves the applicability and accuracy of CO$_2$ corrosion prediction mechanistic model, and provides some reference for the design of oil and gas production, processing and transportation pipeline and related facilities.

10.11885/j.issn.1674-5086.2020.11.20.01