Novel design of lubricant-type vacuum distillation process for lube base oils production from hydrocracking tail oil

Dividing-wall columns(DWCs)are widely used in the separation of ternary mixtures,but rarely seen in the separation of petroleum fractions.This work develops two novel and energy-efficient designs of lubricant-type vacuum distillation process(LVDP)for the separation of hydroisomerization fractions(HIF)of a hydrocracking tail oil(HTO).First,the HTO hydroisomerization reaction is investigated in an experimental fixed-bed reactor to achieve the optimum liquid HIF by analyzing the impact of the operating conditions.A LVDP used for HIF separation is proposed and optimized.Subsequently,two thermal coupling intensified technologies,including side-stream(SC)and dividing-wall column(DWC),are combined with the LVDP to develop side-stream vacuum distillation process(SC-LVDP)and dividing-wall column vacuum distillation process(DWC-LVDP).The performance of LVDP,SC-LVDP,and DWC-LVDP are evaluated in terms of energy consumption,capital cost,total annual cost,product yields,and stripping steam consumption.The results demonstrates that the intensified processes,SC-LVDP and DWC-LVDP significantly decreases the energy consumption and capital cost compared with LVDP.DWC-LVDP further decreases in capital cost due to the removal of the side stripper and narrows the overlap between the third lube oils and fourth lube oils.This study attempts to combine DWC structure into the separation of petroleum fractions,and the proposed approach and the results presented provide an incentive for the industrial implementation of high-quality utilization of HTO through intensified LVDP.

Development of Intensified Technologies of Vanadium-Bearing Titanomagnetite Smelting

It was very difficult for the smelting of vanadium-bearing titanomagnetite by blast furnace because the content of TiO2 of blast furnace slag could amount to 20%-25%.After long term development and continuous improvement,special intensified smelting technologies for vanadium-bearing titanomagnetite by blast furnace were obtained and improved gradually.With the improvement of beneficiated material level and equipment level,smelting intensity has been increased gradually and the highest comprehensive smelting intensity reached 1.45 t/（m3·d）.Technical-economic indexes of blast furnace have also been increased remarkably.The highest utilization coefficient exceeded 2.7 t/（m3·d）on the condition that the burden grade was only about 50%.