加氢裂化装置掺炼辽河原油焦化蜡油技术分析

Analysis of blending coker gas oil from Liaohe crude oil into hydrocracker feed

通过分析加氢裂化装置掺炼焦化蜡油的原料性质,发现掺炼后原料(CGO,VGO)的密度、C+7不溶物及氮含量高于设计值,而硫含量低于设计值,这样的原料不利于精制和裂化反应。掺炼CGO后主要操作参数方面:精制床层平均温度增加8℃,总温升增加5℃;加氢裂化床层平均温度增加10℃,总温升没有变化;装置C+5液收高于掺炼之前;尾油外甩增加。装置运行方面:高氮低硫原料导致精制反应器和裂化反应器的操作条件出现矛盾;循环氢中氨含量过高对裂化剂活性有强烈的抑制作用,并且热高分气换热器结盐速度明显加快。针对这些问题提出了相对应解决措施:确定合理原料掺炼比例;尽可能避免选择高氮低硫原料;增上装置洗盐技术设施。

The feedstock properties were analyzed after blending coker gas oil into the feed of hydrocracking Unit.The performance test results demonstrate that the feedstock （CGO,VGO）density,the C7＋ insolubles and nitrogen content are higher than the design specification and sulfur content is lower than the design.Therefore,the feedstock is unfavorable for the refining and cracking reactions.After blending CGO,the average temperature of refining reactor was raised by 8 ℃,and the overall temperature rise was 5 ℃：The average temperature of hydrocracking reactor bed rose by 10 ℃,and there was no change in overall temperature.The liquid C5＋ product yield was higher than that before the blending; Tail oil was increased.In unit operation,the high-nitrogen and low-sulfur feedstock led to the conflicts of operating conditions between refining reactor and hydrocracking reactor.The high level of ammonia in the recycle hydrogen had a strong inhibitory effect on catalyst activity.The salt deposition rate in the heat exchanger of hot HP separator vapor was accelerated.Appropriate measures have been proposed to solve these problems such as selection of a proper blending ratio of coker gas oil in the feedstock,minimization of high-nitrogen low-sulfur feed and addition of salt removal.