制氢装置转化炉炉管催化剂支托失效分析

对两次检修中所发现的中国石油化工股份有限公司石家庄炼化分公司1号制氢装置转化炉炉管催化剂支托出现损坏的情况做了介绍,并对两种批次的催化剂支托进行了成分分析,对使用Incoloy800H材料、损坏严重的催化剂支托表面宏观照片进行了分析,对损伤支托的横截面进行金相、电镜及能谱检验分析。通过对Cr25Ni20和Incoloy800H两种材料的抗渗碳能力的比较,得出了以下结论:催化剂支托损伤的原因是材料在含氢高温环境下发生了表面渗碳现象,直接导致材料表面组织相变、材料分层、表现材料组织疏松和隆起,并在表面区域晶界上产生了大量的微裂纹,同时引起材料内部有大量的碳化物析出,使得材料的韧性急剧下降,塑性不足。热膨胀后的支托难以回复到原始形态,故在部分破坏的支托管上出现类似"蠕胀"的胀粗现象。结果表明,使用Cr25Ni20材料的抗渗透能力比Incoloy800H要好。

Technical analysis of failure of catalyst support of reformer furnace tube of a hydrogen generation unit

The damages of catalyst support of reformer furnace tubes of No.1 hydrogen generation unit in SINOPEC Shijiazhuang Refining Chemical Co.,Ltd.in two maintenances were introduced.The composition analysis of catalyst support,the study on the macroscopic photo,the analysis of damaged surface of catalyst support of Incoloy800H,the metallographic analysis,energy dispersion spectrum（EDS） analysis,and scanning electron microscope analysis of support＇s section area as well as study on the anti-caburization performances of Cr25Ni20 and Incoloy800H materials have concluded the following： The damages of catalyst support was caused by surface carburization of catalyst support material under high temperature in the presence of hydrogen,which led to phase changes of material surface structure,material stratification,loosening and bulging of surface material structure,large amount of micro-crackings in grain boundary at surface area and eduction of large amount of carbides.All these will reduce the ductility and plasticity of material.Therefore,it is difficult for the catalyst support to restore its original state after thermal expansion,which explains why there are some bulges on the tube of failed support.The anti-carburization performance is greatly improved after application of Cr25Ni20 steel material.