Study On Hydrotreating Residue Reaction Kinetics And Combined Technology

With more and more stringent standards of fuel oils and less and less demand on heavy fuel oil in recent years, the R & D on economic profitable and environmental friendly residue hydrotreating process has become increasing attention to petroleum industry worldwide.In order to optimize the residue hydrotreating process, lower the cost of catalyst, longer stable running and easier operate, the FZC series catalysts are been selected to study. By the study of FZC catalyst, the deactivation of catalysts, key influent factors and grading loading during the residue hydrotreating process, the residue hydrotreating model has been built up. At the same time, a series of SFI combination technologies of residue hydrotreating and RFCC are developed, which can greatly increase the benefit of refineries in whole.One of the key factors in residue fixed bed hydrotreating is the catalyst development and catalyst combination technology.Firstly, on the base of the characteristics of residue hydrotreating reaction and catalyst, various types of FZC catalyst are introduced and evaluation results of activity and stability are outlined, which provides the basic information for FZC series catalyst combination.The performance test results showed that, the catalyst of FZC series can be the same technical tier as the reference catalyst both in physic-chemical specification and reactive activity and has well long-term stability.Secondly, based on simulation and analysis of the operation data with FZC series catalysts in three commercial units of Maoming, Qilu and Hainan, residue hydrotreating deactivation kinetics models have been established. And reaction kinetics model parameters and deactivation kinetics model formula have been set up, which is used in predicting the impurities in products and catalyst cycle length and the calculation results well match with those of commercial running.On the basis of reaction kinetics model parameters and deactivation kinetics model formula, pilot plant test had been conducted to show the effects of the properties of feedstock and operating conditions on residue hydrotreating process, and correction factors impacting on feedstock and operating conditions have thus been established. Meanwhile, a kinetics research method of optimization of various types of catalyst combination loading ratio has been proposed due to catalyst un-synchronous deactivation in commercial applications. Finally, to overcome the shortage of existing combination process, a series of SFI combination technologies of residue hydrotreating and RFCC are developed, whose main feature is that there is no fractionation system in residue hydrotreating unit, and FCC diesel, recycle oil and/or FCC slurry oil recycle back to the residue hydrotreating unit. SFI combination technologies can achieve maximum production of high value gasoline by residue deep conversion and therefore increase the utilization of crude resources. SFI combination technologies are also characterized by simpler process flow, lower capital and operation cost, which can greatly improve the overall economic benefits for refineries.