异构化产品油氯含量超标原因分析及整改措施

Analysis of chloride content in isomerization products exceeding standard specifications and countermeasures

针对某石化公司600 kt/a C_5/C_6轻石脑油异构化装置产品油氯含量超标的问题,发现混合原料中重组分C_7^+质量分数高达4%以上;反应器入口温度降低至120℃以下;四氯乙烯无法完全分解及装置操作负荷小于70%等均是可能导致异构化产品油氯含量超标的因素。通过采用降低轻抽余油含量以保证混合原料C_7^+质量分数低于2%;提高反应器入口温度至130℃以上;采购专利商推荐的四氯乙烯种类;增加产品循环油以保证装置负荷在设计负荷70%以上等措施之后,异构化产品油中氯质量分数不大于5μg/g,氯含量有所减少,指标有所好转。

In the analysis of off-specification problem of chlorides in isomerate produced in a 600,000 TPY C5/C6 light naphtha isomerization unit,it was found that the mixed feed contained over 4% of C7^＋,the outlet temperature of reactor was reduced to lower than 120 ℃,it was difficult for tetrachloroethylenes to be cracked,and the operating capacity of the unit was lower than 70% of the design capacity. All these may contribute to the off-specifications of chlorines in isomerate. After taking of following measures such as reducing the raffinate to insure that the C7^＋ in the mixed feed is lower than 2%,raising the reactor inlet temperature to over 130 ℃,purchasing tetrachloroethylenes recommended by licensor,the clorines in product oil have been reduced and associated specifications have been improved.