Direct Evaluation Method of Inner Corrosion of Sulfur-Containing Wet Gas Pipeline

The direct evaluation method for corrosion in wet gas pipelines (WG-ICDA) can be used to classify the risk sections of pipelines, realize the hierarchical treatment of the entire pipeline, greatly reduce the cost of inspection, and improve the safety performance of the pipeline. However, due to the difference of the medium environment, the direct evaluation method of internal corrosion has relatively poor adaptability to certain pipelines, and it is difficult to accurately divide the high-risk sections. Therefore, numerical simulation was used to study the influence of sulfur-containing wet natural gas on pipeline corrosion. The results show that the corrosion in the natural gas pipeline was greatly affected by the accumulation of liquid. The accumulation of liquid in the pipeline created conditions for H₂S/CO₂ corrosion and was an important factor in the occurrence of local corrosion. High effusion in the tube, could form a continuous effusion zone, the bottom of the effusion corroded content of slight, and the corrosion at the gas-liquid interface was more serious. The less effusion in the tube, due to changes in pressure and temperature, the effusion was scattered and disorderly, and internal corrosion was instead severe. Based on this, the indirect evaluation process in the direct evaluation method of wet gas pipeline internal corrosion was optimized and applied to a wet gas pipeline in Tahe Oilfield. The evaluation results showed that the proposed direct evaluation method for internal corrosion of wet gas pipelines could identify the corrosion risk of sulfur-containing wet gas pipelines more accurately, and effectively guarantee the safe operation and management of on-site wet gas pipelines.