Study On The Production Process Of Bright Oil

Bright oil is a high value-added product,its characteristic is high viscosity and high flash point.In the oil blending process,it is used to improve the viscosity of the lubricating oil,reduce the usage of viscosity index improver,and improve the oxidation stability of lubricating oil.The production of blight oil mainly uses vacuum residue as raw material,through deasphalting,solvent refining/hydrofining,dewaxing,supplementary refining and other processes.This paper optimizes the production process of bright oil by changing the processing order of each unit.In this paper,the propane deasphalting oil of vacuum residue from a refinery is used as raw oil,and the bright oil is produced by NMP refining,fixed bed hydrogenation and ketone benzol dewaxing.The combined process of NMP refining-hydrofining-ketone benzol dewaxing combined with NMP refining-ketone benzol dewaxing and hydrofining were investigated,and some of the processes were optimized.NMP refining-hydrofining-ketone benzol dewaxing combined process:first,deasphalting oil was refined by NMP,Then,NMP refining oil is hydrogenated under the reaction of Ni-W/?-Al₂O₃ catalyst.The reaction pressure is 8MPa,temperature is 350?,volume space velocity is 0.5h^-1,hydrogen oil ratio is 500:1.Then,the hydrofining oil was dewaxed at-15?with ketone and benzene.The colour of the product oil is 7.5,the sulfur content is 1059?g/g,the nitrogen content is 1026?g/g,the pour point is-11?,the viscosity index is 106,initial oxidation temperature is 221.9?,and the yield is 52%.NMP refining-ketone benzol dewaxing and hydrofining combined process:First,deasphalting oil was refined by NMP;Then,NMP refined oil is dewaxed with ketone and benzene and then hydrogenated under the action of Ni-W/?-Al₂O₃ catalyst.The hydrogenation reaction conditions are the same as above conditions,the colour of the obtained product oil is4,sulfur content is 1126?g/g,nitrogen content is 1120?g/g,the viscosity index is 123,initial oxidation temperature is 256.6?,and the yield is 50.3%.Compared with the two processing techniques,the product oil obtained from the NMP refining-hydrofining-ketone benzol dewaxing combination process has a relatively low sulfur content and nitrogen content,and the desulfurization and denitrification effect of the process is better.The product oil obtained from the combined process of NMP refining-ketone benzol dewaxing and hydrofining process has lower chromaticity,higher viscosity index and better oxidation stability.