含硫气田净化厂原料气过滤分离设备腐蚀主控因素研究

Study on the main corrosion controlling factors of sour natural gas filtration and separation equipments of the purification plant for sour gas field

关键词:  含硫气田  天然气净化  过滤分离设备  腐蚀  失效分析 

Key words:  sour gas field  natural gas purification  filtration and separation equipment  corrosion  failure analysis

摘要:

含硫气田天然气净化厂原料气过滤分离设备为关键设备,其腐蚀失效情况也备受关注。现场调研发现,使用一段时间后,分离设备底部积液位置出现腐蚀层,且分离设备存在较多鼓泡。通过开展金相分析、理化性能分析及腐蚀微观分析,确定了设备失效原因,室内模拟现场条件找出腐蚀失效主控因素。结果 表明,在材料力学性能、化学成分满足标准要求的前提下,材料本身存在较多夹杂是导致设备鼓泡失效的主要原因,随着H₂S与CO₂分压比的增加,腐蚀速率增大,氢鼓泡现象更加严重。 

Abstract:

The filtration and separation equipments are the key equipments of natural gas purification plant for sour gas field, the corrosion failure of the equipments reveives much concern. Field survey results showed that the corrosion layer appeared at the fluid position of the bottom of equipments after a period of time, and there were more bubbles at the separation device. The failure factors were ensured by metallographic analysis, physical and chemical properties analysis and corrosion microscopic analysis, and then the main corrosion control factors were founded by laboratory simulation of field. The results showed that under the premise of the material mechanical properties and chemical composition meeting the requirements of the standard, the main factor for equipment failure of bubbling was impurities in the materials. As the H₂S and CO₂ partial pressure ratio increasing, the corrosion rate increased, and the hydrogen bubble phenomenon became more serious.