| In this paper, a duplexing integrated technology was developed to make use of deasphalted oil (DAO) efficiently, for the purpose of improving the utilization of heavy components in refineries. The process composed of two parts, the first part was to find a selective solvent to extract the deasphalted oil (DAO) received from the solvent deasphalt process in refineries, which resulted in light raffinate and deoiled asphate (DOA). The light raffinate can be used as FCC feedstock to improve the yield of gas oil; and the extract oil or DOA was used as soft components of high-grade road blending asphalt, so as to make it possible to produce high-grade road blending asphalt with the supply of paraffine crude oil.A set of single stage extraction experiments were conducted to observe the extraction performance of five kinds of solvents widely-used in industry, including furfural, epoxy chloropropane, sulfonlane, N-formylmorpholine and N-methylpyrrolidone. Among these, DAO-NMP system and DAO-furfural system were found to perform the best with regards to both the dissolubility and selectivity. The experimental results showed that the optimal extraction conditions of the two systems above were as follows:in DAO-furfural system:the temperature range was 75℃, and the solvent to oil ratio was 3.0. In DAO-NMP system, the temperature was controlled within 70-75℃, and the solvent to oil ratio was between 1.5 and 2.0.Based on the experimental work, decanter module was used to simulate and optimize single stage phase equilibrium experiments of the two systems above with the aid of process simulation software Aspen Plus. Kuop method had been adopted to describe the characteristics of DAO in order to investigate the effect of various thermodynamic conditions on the extraction results. UNIFAC method was employed to screen the extraction effects in comparison with phase equilibrium experiments results. In DAO-furfural system:the simulation results of seven experiments were in agreement with the calculated results with satisfaction of error requirements(5%) under the same condition of DAO group composition. In DAO-NMP system:five experiments'simulation results were consistent with the calculated results with satisfaction of error requirements(5%) under the same condition of DAO group composition. A extract model was set up on the basis of these results to simulate and calculate two-stage extraction processes of the two systems respectively, the calculation results can be used to predict the industrial practical operation with guiding significance.A turntable extraction tower was used to extract DAO continuously under different conditions using the solvents of sulfonlane, N-formylmorpholine. NMP and furfural. Extraction operation conditions were optimized and the stability of solvent recovery system was studied. From four sections of continuous extraction experiments, it was found that:1) furfural and NMP were found to perform the best of five solvents, and it was in accordance with the single stage phase equilibrium experiments; 2) NMP was found to perform the best with regards to both the yield and the selectivity of aromatic; however, the relative density of NMP and crude oil was too close to delaminate two-phase, and the saturates'content underlying was too high. Thus, it was more efficient to mix the solvent and raw oil statically or dynamically, and then the mixture was sent into the tower to delaminate.3) The Flashing-Stripping flow was adopted to recover solvent, the recovery rate was high, and the requirements of duplexing integrated technology can be satisfied.The performance of DOA with heavy traffic paving petroleum asphalt was studied. And the microstructure and rheological property of DOA and blending asphalt were characterized. The results showed that the asphalt production received from experiments of two components blending of DOA with initial (topped) heavy slurry can meet the standard of GB/T15180-2000 AH-90, except needle penetration; after increasing DAO extract oil with furfural, blending asphalt No.l and blending asphalt No.2 derived from experiments of three components blending of DOA, DAO extract oil with furfural and topped heavy slurry had a obviously decreasing wax content; the ductility at 10℃and 15℃were larger than 150 cm, showing very good low temperature performance and ageing resistance.The FCC performance of DAO and raffinate was also tested and discussed. Cracking performance comparison results showed that the light oil yield and convertion of raw material A and B increased sharply, while the heavy oil yield decreased substantially. It showed that the FCC performance of raw material A and B was superior to DAO. The composition and characterization of the cracking products suggested that the density of gasoline fraction derived from raw material A, raw material B and DAO were 771.5kg/m3,759.5kg/m3 and 758.3kg/m, sulfur contents were 0.27m%,0.30m% and 0.31 m%; olefin contents were 39.1v%,46.5 v% and 52.6 v%; aromatic hydrocarbon contents were 43.9 v%,33.3 v% and 31.2 v% respectively. Compared with the untreated DAO, the olefin contents of catalytic gasoline of raw material A and raw material B dropped sharply, while the aromatics contents rose sharply and sulfur contents also decreased. It implied that the raffinate obtained from the furtural solvent extraction of DAO was suitable to produce catalytic gasoline with better quality. The gum contens in the raw material A, raw material B and DAO were 244mg/(100ml), 362mg/(100ml) and 405 mg/(100ml) respectively, implying that catalytic diesel properties of raw material A and raw material B were superior to DAO. It was in agreement with the experimental results, which showed that the FCC performances of raw material A and raw material B were superior to DAO.
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