天然气中汞的腐蚀机理及防护措施

天然气中汞的危害主要体现在高毒性、腐蚀性及引起天然气化工用催化剂中毒,直接影响到含汞天然气开发和利用的安全性。分析了汞对多种金属的腐蚀机理。汞对不同金属的腐蚀程度有很大差异,汞对铝制设备的腐蚀性较强,对以碳钢、合金钢、不锈钢为材质的管道和设备的腐蚀性较弱。提出了脱除天然气中的汞,降低天然气中汞含量是防护汞腐蚀最有效的措施,同时认为使用防汞腐蚀涂层材料、即时清除管道和设备中聚积的汞和定期检测汞腐蚀情况等工艺措施也可降低汞腐蚀风险,预防汞腐蚀事故的发生。

Corrosion mechanism of mercury in natural gas and protective measures

The hazards of mercury in natural gas are mainly reflected in its high toxicity,corrosion and causing catalyst poisoning in utilization of natural gas for chemical products,which threatens the safety of development and use of mercury-containing natural gas.Corrosion mechanisms of mercury on a variety of metals were analyzed.The degrees of mercury corrosion for different metals were diverse.Mercury had stronger corrosiveness on aluminum equipments than on pipelines and equipments made of carbon steel,alloy steel and stainless steel.It was proposed that removal of mercury in natural gas to decrease its concentration was the most effective anticorrosive measure for mercury-containing natural gas,and that using of anti-mercury corrosion coatings,immediately removal of the accumulated mercury in pipelines and equipments and regular detection of mercury corrosiveness could also reduce the mercury corrosion risk.