沸腾床加氢-焦化组合工艺制备低硫石油焦

对沸腾床加氢-焦化组合工艺制备高品质石油焦的工艺路线进行研究，探究沸腾床未转化油（UCO）的焦化规律。结果表明：渣油沸腾床加氢反应过程中，提高温度或降低空速有利于渣油转化率和杂质脱除率提高；同样的操作区间内，渣油转化率的变化明显大于杂质脱除率；随着渣油转化率增加，UCO硫含量先降低再升高。UCO焦化过程中原料中60%左右的硫转移到焦炭中，明显高于渣油焦化过程中硫转移到焦炭的比例（约42%）；相比于渣油直接焦化得到的焦炭，较低硫含量的UCO制备的石油焦品质明显提升。UCO焦化所得石油焦收率和硫含量分别与UCO的残炭值和硫含量呈现良好的线性关系，可根据所需低硫焦牌号来指导沸腾床加氢过程的工艺优化。

COMBINED PROCESS OF EBULLATED BED HYDROCRACKING AND DELAYED COKING TO PREPARE LOW SULFUR COKE

The fluidized bed residue hydrotreating technology has a remarkable effect on the desulfurization and quality improvement of coking feedstock.The high quality coke prepared by combined process of ebullated bed hydrocracking and delayed coking was investigated and the coking law of unconverted oil(UCO)from ebullated bed was explored.The results showed that the temperature increase or the space velocity decrease were beneficial to residue conversion and impurity removal in the ebullated bed hydrogenation process.Within the same operating range,residue conversion rate was significantly higher than the impurity removal rate.With the increase of residue conversion,sulfur content of UCO decreased first and then increased.In the process of UCO coking,about 60%of sulfur from UCO was transferred into coke,higher than the sulfur ratio into the coke from residue coking process(about 42%),and the quality of petroleum coke prepared by UCO can be significantly improved compared with residue as feed.The yield and sulfur content of petcoke from UCO feed has a good linear relationship with carbon residue and sulfur content of UCO,which can be used to guide the optimization of ebullated bed hydrocracking process according to the required low sulfur coke grade.