Qi Gang, Dong Yanli, Feng Yongxiang, Wei Jianjian, Han Pengju, Bai Xiaohong, He Bin
College of Civil Engineering, Taiyuan University of Technology Taiyuan 030024 P. R. China
Civil Engineering School of Environment and Safety Engineering, North University of China No. 3 Xueyuan Road Taiyuan 030051 Shanxi P. R. China.
RSC Adv. 2022 Oct 10;12(44):28767-28779. doi: 10.1039/d2ra04889b. eCollection 2022 Oct 4.
In this experiment, Q235 and X80 carbon steels, which are widely used in oil and gas pipelines and ancillary facilities, were selected to study the changes in the corrosion behaviour and mechanism of carbon steels in the process of natural saline soil cooling to a freezing state through electrochemical testing. The equivalent circuit model of carbon steel before and after the freezing phase transformation in the soil was determined. Based on the corrosion kinetic parameters and soil thermodynamic changes, the influencing factors of steel corrosion during the cooling process were systematically analysed. It was found that temperature mainly affected carbon steel corrosion by changing the properties of the solution. The main factors affecting the corrosion behaviour of the carbon steel were the thermal motion of molecules, ions, and electrons in solution, oxygen dissolution and diffusion, ion adsorption, diffusion mass transfer, and unfrozen water content change during the cooling process.
在本实验中，选用了广泛应用于油气管道及附属设施的Q235和X80碳钢，通过电化学测试研究碳钢在天然盐渍土冷却至冻结状态过程中腐蚀行为及机理的变化。确定了土壤中碳钢冻结相变前后的等效电路模型。基于腐蚀动力学参数和土壤热力学变化，系统分析了冷却过程中钢材腐蚀的影响因素。研究发现，温度主要通过改变溶液性质影响碳钢腐蚀。冷却过程中影响碳钢腐蚀行为的主要因素有溶液中分子、离子和电子的热运动、氧的溶解与扩散、离子吸附、扩散传质以及未冻水含量变化。
