渣油加氢反应器顶部催化剂结垢原因及防止措施

CAUSES AND CURES FOR CATALYST FOULING AT THE TOP OF RESIDUE HYDROTREATING REACTOR

齐鲁石油化工公司胜利炼油厂减压渣油加氢脱硫装置的前置反应器在运行中压力降上升过快，最快时１３８天即达到极限值０７３５ ＭＰａ。检查发现，主要是由于床层顶部结垢所致。分析结垢的原因，一是原料过滤器反冲洗油中含杂质过多，苯不溶物达２４００μｇ／ｇ；二是原料过滤器内漏。对垢样的分析发现，其主要成分是以磁性磺铁矿（Ｆｅ_(０．９５)Ｓ）形式存在的硫化亚铁，其质量分数达４８．５４％。由此提出了更换反冲洗油，采用在线置换催化剂工艺，更换容垢能力强的催化剂，采用除铁工艺和添加中止剂以减少硫化亚铁生成等措施。

The increase of pressure drop in the front reactor of vacuum residue hydrodesulfruization unit in Shengli Refinery of Qilu Petrochemical Company was so quick, even reached the limited value of 0. 735 MPa after 138 days. The examination found that the main cause was catalyst fouling at the top of the bed. One cause of fouling was much impurities in back-washing oil for the feedstock filter, with benzene insolubles reaching 2400 μg/g. The other is inner leaking of the feedstock filter. Analysis of fouling Samples found that the main composition is ferrous sulfide in the form of magnetic pyrite (Fe_(0.95)S), constituing 48. 54% in weight. Measures such as altering backwashing oil,on-line catalyst replacing, using catalyst with strong resistance to fouling, adopting iron removing technology and adding terminator to retard the formation of ferrous sulfide were proposed.