连续重整催化剂严重氮中毒和活性恢复案例分析

CASE ANALYSIS ON SEVERE NITROGEN POISONING AND ACTIVITY RESTORE OF CONTINUOUS REFORMING CATALYST

以某公司重整装置2014年2月因水、氮超标导致催化剂氮中毒和后续活性恢复为例,分析连续重整反再系统出现高水、高氮、低氯的环境后,催化剂发生严重氮中毒时装置的工艺表现以及处理方案。结果表明:由于加工福蒂斯等高氮原油比例过高,造成重整原料油氮含量升高,装置负荷优化调整大而注氯量偏低,同时重整再生空气干燥器干燥效果下降等原因,共同造成催化剂氮中毒,活性大幅降低,出现反应温降降低、产氢降量、生成油芳烃产率大幅下降。通过调整加工原油比例,优化原料预加氢操作、降低重整加工负荷和反应苛刻度、更换空气干燥剂等一系列措施,减少系统中氮和水等毒物的携带量,并提高重整再生注氯量等措施,使重整催化剂氮中毒得以有效控制并逐渐恢复活性。

Taking the case of catalyst nitrogen poisoning and subsequent activity recovery caused by excessive water and nitrogen of the reforming unit in some company in February 2014,process expression and treatment project of the unit were described in case of the following operation situation happening such as high water,high nitrogen and low chlorine in the continuous reforming reaction-regeneration system.The results showed that due to the excessive proportion of high nitrogen crude oil from Fortis and etc,nitrogen content of the reformer feed oil was increased,optimization and adjustment on the unit load was large and yet the chlorine injection was lower;meanwhile,drying effect of the regeneration air dryer using for the reformer was declined.All of the previous mentioned factors caused the phenomenon such as the catalyst nitrogen poisoning,significant activity reduction,the bad states of the unit appearing such as reduction in the reaction temperature drop and hydrogen production,severe drop in the aromatics yield.By a series of measures such as adjustment in crude oil mixture ratio,optimization on the raw material pre hydrogenation operation,reduction in the reforming load and reaction severity,replacement in the air dryer and etc,the carrying amount of the catalyst poison such as nitrogen and water in the system was reduced;chlorine injection for the reformer regeneration was increased,so nitrogen poisoning of the reforming catalyst could be effectively controlled and its activity was gradually restored.