Study On Removing The Solid Particles Of Slurry By Solvent Extraction And Sedimentation

Fluidized Catalytic Cracking(FCC)slurry is a kind of complex mixture with high aromatics content.The slurry which contains lots of aromatic hydrocarbons,mainly short side chain of polycyclic aromatic hydrocarbons,can be used as good raw material of value-added chemical products such as carbon black,carbon fibers and needle coke.However,the presence of tiny particles,nitrite and sulfur in FCC slurry,which seriously affect the further processing and utilization of FCC slurry.Therefore,it is of great significance to study the removal of solid particles and heteroatom in slurry.In this paper,Liaohe fluid catalytic cracking slurry and its solid particles are systematically characterized as the main research object.Then,on the basis of self-made extraction unit with microwave,the optimum operating conditions were optimized,and the effects of different diluents and microwave on slurry properties and solvent extraction efficiency were investigated.The removal mechanism of solid particles in solvent extraction was preliminarily discussed,and the internal factors which affect the solvent extraction were revealed.The results indicated that the optimum extraction conditions are as follows: extraction temperature is 70?,the ratio of diluent(B)to oil is 0.6:1,the ratio of extractant to oil is 1:1,the extraction time is 30 minutes,the stand temperature is 70? and the stand time is 3h.The removal efficiency of solid content can reach about 97% and the recovery rate of oil is more than 93%.During studying the effects of diluent composition and microwave on the solvent extraction,it was found that the viscosity of oil slurry decreases and the adsorption layer on the surface of solid particles changes with the addition of different diluents,.In the presence of microwave,microwave can reduce the viscosity when the viscosity of slurry is in a high level,and the particles in the slurry will be clustered.Microwave can play a synergistic effect with polar solvent and the oil properties could be improved when the removal rate of particles was significantly increased and the content of heteroatoms in the slurry was decreased.