加氢裂化装置产品重石脑油硫含量的控制

CONTROL OF SULFUR CONTENT IN HYDROCRACKING HEAVY NAPHTHA

分析了中国石化股份有限公司天津分公司加氢裂化装置重石脑油总硫含量超标的原因。偶发事故造成的床层超温引起催化剂积炭增加,堵塞了催化剂微孔,减少了活性中心数量,造成裂化催化剂的加氢功能与裂解功能不匹配,同时后精制催化剂又无法全部脱除裂化过程中产生的硫醇,造成重石脑油总硫含量超标。通过调整反应工艺条件及重石脑油的切割点,生产的重石脑油总硫含量小于0.5μg/g,满足重整装置的原料要求。

The heavy naphtha produced from hydrocracking plant of SINOPEC Tianjin Company was disqualified due to the high total sulfur content and related investigation was carried out to solve the problem. It was found that the temperature of the catalyst bed was out of control during an occasionally equipment breakdown which resulted in catalyst coking and aggregation of active metals particles. The hydrogenation activity and the cracking activity of the hydrocracking catalyst were not in the optimum coordination mode since the number of active sites reduced. Furthermore, the affected post hydrofining catalyst fell to remove all the mercaptans formed in the cracking reactions. After properly adjusting the process operation conditions and reconsidering the cutting point of heavy naphtha, the total sulfur content of the produced heavy naphtha was less than 0.5 μg/g, meeting the feedstock requirement of reforming process perfectly.