减压分馏塔塔顶蒸汽喷射泵的失效原因

Failure Reason of Steam Jet Pump at Top of Vacuum Distillation Tower

某石化企业减压分馏塔塔顶SAF 2205双相不锈钢蒸汽喷射泵发生泄漏,为明确其失效原因对其化学成分、腐蚀形貌和腐蚀产物进行了分析,并提出了相关防护建议。结果表明:蒸汽喷射泵的失效主要归因于严重的选择性腐蚀。在喷射泵的服役期间,由于流动和热交换的作用,水蒸气发生冷凝并溶解酸性气体,从而形成酸性液滴,使喷射泵内壁处于典型的HCl-H2S-H2O腐蚀环境中,壁面发生选择性腐蚀;同时,高速流体对喷射泵的冲刷加速了泵体的减薄。

The steam jet pump made of SAF 2205 duplex stainless steel at the top of the vacuum distillation tower in apetrochemical enterprise leaked.In order to clarify the cause of its failure,the chemical composition,corrosion morphology and corrosion products were analyzed,and some protective suggestions were proposed.The results show that severe selective corrosion was the primary reason for the failure of the steam jet pump.During the service of the jet pump,due to the action of flow and heat exchange,the water vapor condensed and dissolved acid gas,thus forming acid droplets,so the inner wall of the jet pump was in a typical HCl-H2S-H2O corrosion environment,and the wall surface was selectively corroded.At the same time,the erosion of the jet pump by high-speed fluid accelerated the thinning of the pump body.