Study On Strengthened Residual Oil Coking Process

Along with the world crude oil changes to the heavy and inferior, the coked process play an important role in residual oil change the nature Quality have the broad prospects for development. This article from the perspective of coking materials, combined with the dispersion characteristics of residue, by adding alkaline additive manner, to promote residual oil raw material activated state in order to achieve reduction in the coking reaction in the coke and dry gas yield and improve of the yield of light oil. The result indicated: Joins the alkaline matter in the Liaohe vacuum residuum, reduced the residual oil system's kinematic viscosity and the pour point, raised the residual oil system's mass fraction normalized conductivity, played a positive role in promoting the colloidal stability of residual oil raw material. Among them the action effect of weak basicity material (NH4)2CO3 is most obvious; it makes Liaohe residual oil system is at the best activated state.This article investigated the action effect of alkaline additive in coking reaction process, and? has carried on the simulation coking reaction experiment separately to three kind of alkalinity strengthening assistant. the results showed that The raw material active change enhanced the depth of conversion of raw material; Under same response condition, The yield of clean oil raised 0.8~2 percentage point, and the yield of gasoline increased 0.2~0.5 percentage point, diesel oil receiving rate increased 0.5~1.7 percentage point, the dry gas and coke receiving rate reduces obviously。 The union residual oil dispersion theory and the second liquid phase coking theory attempt to preliminary interpretation the action mechanism of strengthened coked: The addition of alkaline additive may response to the carboxylic exists in the glial and asphaltene and produce the RCOO- ion, forms the anion surface active agent, Reduces the asphaltene, the sol and its solvation layer around the interfacial tension, enhances the dissolving capacity of dispersion medium; And alkaline hydroxyl through the surface of the asphaltene adsorption, to prevent the association of asphaltene colloidal particles and inhibit the residual oil system's phase separation, has the peptization stabilization to the asphaltene. Moreover, the introduction of alkaline additives can also increase the dispersion of the asphaltene in the residual oil, can produce more, smaller coke center in the coking reaction process, effectively reducing the burnt granularity and quantity.