高含硫天然气脱硫系统富胺液管线腐蚀问题浅析

Analysis on corrosion of rich amine liquid pipeline in high sulphur natural gas desulfurization system

对富胺液管线出现的腐蚀问题进行原因分析,从管段部位、服役年限等方面统计腐蚀缺陷,分析得出其腐蚀机理为RNH_(2)-H_(2)S-CO_(2)-H_(2)O型腐蚀、磨损腐蚀、电偶腐蚀、应力腐蚀等共同作用。从运行阶段的缺陷筛查、缺陷管线处置、在线监测系统配置、工艺优化等方面提出管控措施,从规范相关管线管件服役年限、部分或全部管线材质升级、在线监测优化、腐蚀失效构件取样分析、焊接施工过程质量管控等方面提出技术改造措施,保证装置的长周期平稳运行。

The causes of the corrosion problems of the rich amine liquid pipeline were analyzed,and the corrosion defects were counted from the aspects of pipe section position and service life.The analysis showed that the corrosion mechanism was the combined action of RNH_(2)-H_(2)S-CO_(2)-H_(2)O corrosion,wear corrosion,galvanic corrosion and stress corrosion.Put forward control measures from the aspects of defect screening,defective pipeline disposal,online monitoring system configuration,process optimization,etc.in the operation stage,and put forward technical transformation measures from the aspects of standardizing the service life of relevant pipeline fittings,upgrading of some or all pipeline materials,online monitoring optimization,sampling and analysis of corrosion failure components,quality control during welding construction,etc.,so as to ensure the long-term and stable operation of the device.