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Rising crude oil prices and oil-poor country rich in coal situation prompted coal oil, coal gas, coal, methanol and ethylene glycol coal and other technologies continue to flourish. Mixing with coal tar and crude oil distillation residue can be directly expanded refining resources, improve product quality and after processing to increase refinery economic benefits, has high research value and industrial applications. The paper first analyzes the coal tar residue incorporation on basic physical and chemical properties as well as its surface tension, the experimental results show that the incorporation of coal tar residue can reduce the viscosity of the mixture, the metal content, the average molecular weight and colloidal stability, help to improve the effect of solvent deasphalting, but also increase the residual carbon content in the mixed feed. Extract surface tension results showed that with the increase in the amount blended coal tar extract the surface tension decreases and then increases, the amount of low-blending system can reduce the surface tension, improves deasphalted oil (DAO) of nature. On this basis, the paper in the solvent deasphalting to design a small pilot plant, using ethyl acetate as the solvent, the effects of atmospheric conditions blending coal tar residue solvent deasphalting process, the solvent ratio, extraction temperature, the amount of coal tar blending effects were investigated and optimized process conditions to optimize the extraction temperature is 30 ℃, solvent ratio 6:1, the amount of 10% blending of coal tar. Under the optimal process conditions, DAO yield of 65.01%, 14.95% carbon residue of the metal Ni, V content was 5.27μg / g and 18.75μg / g, sulfur and nitrogen content of 3.19% and 0.27%. Deasphalting directly compared with the residue, DAO yield was improved by 3.02%, Ni and V content is reduced 0.39μg / g and 0.89μg / g, reduced sulfur and nitrogen content of 0.10% and 0.01%, a little carbon residue increase of 0.27%. The solvent deasphalting nature of the product analysis found that blending a small amount of residual oil saturation can be increased coal tar and aromatic grading component of the extraction efficiency and to improve the performance of DAO catalytic cracking. Finally, the paper uses FT-IR and 1H-NMR and other advanced analysis tools to calculate the structural parameters of the raw material, coal tar residue and to establish the appropriate structure model and calculate the solubility parameters of coal tar residue and were 17.03 (MPa ) 1/2 and 17.63 (MPa) 1/2. Incorporation of a mixed system of coal tar residue solubility parameter is greater than the solubility parameter closer to the solubility parameter of ethyl acetate, thus increasing its solubility in ethyl acetate, to improve deasphalting effect of increasing the yield DAO.
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