Study On Phase Separation And Inhibition Of Heavy Oil And Coal Tar Blending System

China is the world's largest coal producer especially in the production of the low metamorphic coals.A certain amount of coal tar,a poor quality heavy oil resource,is produced in the medium-low temperature coking process of the low metamorphic coals.This thesis is to mix a certain proportion of YLAR with MRAR,in which flocculation and phase separation occur.And then to treat it with heavy oil technology and study the phase separation behavior and inhibition of the blending system from the view of phase separation and stability.The thesis studied the colloidal stability of MRAR/YLAR blended at 200°C,characterizing the aggregation morphology and stability of the system by optical microscopy and ultraviolet spectrophotometry,and then characterized asphaltenes with elemental analysis?FT-IR?XRD?relative average molecular mass(VPO),small angle X-ray scattering;Basing on the MRAR: YLAR =7:3 system,the effect of the type and content of surfactants on phase separation was studied,the viscosity and stability of the system was characterized and the asphaltene content and structure was analyzed.Finally,the hydrothermal reaction behavior of MRAR:YLAR=7:3 blending system with surfactants was investigated.The results show that the addition of YLAR destroys the equilibrium state of the colloidal system of heavy oil system and changes the aggregation morphology of the system.And with the addition of YLAR the particle is aggregated and the association size of asphaltene,the relative average molecular mass is increased,the stability of the system is decreased;The results of the effect of surfactants on the phase separation of MRAR/YLAR blending system show that the addition of cationic surfactant CTAB effectively enhances the dispersion and stability of the system.The results of SARA analysis show that the content of resin increased,the content and association size of asphaltene decreased along with the increase of CTAB content.With the addition of SDBS,the content of asphaltene increase,which does not effectively enhance the stability of the system;The hydrothermal reaction behavior on MRAR/YLAR blending system with surfactants show that with the addition of SDBS,the degree of aromaticity is reduced,the trend of condensation is weakened,the phase separation is slowed down and the coking formation is delayed.With the addition of CTAB,the cracking condensation reaction is aggravated,the aromaticity is increased and the degree of condensation is increased.The morphology evolution of toluene insolubles showed that the aggregation of toluene insoluble particles became more loose and dispersed with the addition of SDBS.