Hydrocracking Performance Of Dalia VGO And Dalia VGO Blended With LDAO

The development of new heavy oil processing technology and an efficient flexible clean oil production technology is the most important issue in the petroleum refining industry.China University of Petroleum(Beijing)extracted some light deasphalted oil(LDAO)with good nature from vacuum residuum for further utilization.In this study,we blended some LDAO with vacuume gas oil(VGO)as harmonic components for hydrocracking feedstock,in order to get higher light oil yield with relatively low cost.In this research,Dalia VGO and Dalia VGO blended with LDAO were employed as feedstocks for hydro-refining and hydrocracking process.The hydrofining catalyst DN–3551 and hydrocracking catalyst Z-3723 were both provided by Huizhou Refinery.By the single factor variable method,the effects of various parameters,such as reaction temperature,pressure,H2/Oil ratio(v/v)and mass space velocity,had been systematically investigated by using a 10 ml fixed-bed hydrocracking mirco-reactor.Through the analysis of the S/N contents in products and the products distribution,the reaction rule was concluded and the process operation conditions were optimized.At the same time,a first-order hydro-desulfurization multi-parameter kinetics was established to calculate the S contents in hydro-refining products.The results could lay a foundation for industrial application in the future.Through analysis of experimental data,it can be concluded that it can be concluded that for three kinds of hydro-refining feedstocks,namely Dalia VGO,Dalia VGO blended with 10 wt% and 20 wt% LDAO,the sulfur content in hydrorefining products under the optimal conditions were 77.26 mg/L,115.93 mg/L and 136.04 mg/L respectively,and nitrogen contents were 4.81 mg/L,9.68 mg/L and 25.29 mg/L respectively.The first-order hydro-desulfurization multi-parameter kinetic model established based on the hydrofining data fitted well with the experimental values,and the relative error was very small.It showed that the kinetic model can be used to calculate the sulfur content in hydro-refining products under different reaction conditions,and also provide guidance for the choice of process conditions in industrial production.For three kinds of hydrocracking feedstocks,namely Dalia VGO,and Dalia VGO blended with 10 wt% and 20 wt% LDAO,the sulfur contents in hydrocracking products under the optimal conditions were 9.82 mg/L,37.54 mg/L and 79.88 mg/L respectively,and nitrogen contents were 0.35 mg/L,6.53 mg/L and 16.68 mg/L respectively.When the objective product was gasoline,the gasoline yields for three feedstocks under optimal conditions were 81.30%,74.50% and 70.20% respectively;When the objective product were kerosene and diesel,the kerosene and diesel yields for the three feedstocks under optimal conditions were 45.30%,45.30% and 50.00% respectively.The resutls showed that Dalia VGO is more prone to cracking and can yield more naphtha.In addition,with the increasing of percentage of blended LDAO,the gas and gasoline yields decreased,but the kerosene and diesel yields increased.when the hydrocracking feedstock was VGO blended with 20 wt% LDAO,under the condition of 400 ?,10 MPa,1.0 h-1 space velocity and 1000 H2/Oil ratio,the tail oil yield was only 6.20%,the gasoline yield 49.70%,the kerosene and diesel yield 43.10%,indicating that the products distribution is good.So it can be concluded that LDAO could be a blended in VGO as hydrocracking feedstock,and the recommended blending ratio of Dalia LDAO is 20%.