Patent ID: 7857964

Claim:
A refining method for refining heavy oil and obtaining a refined oil, comprising: performing a solvent extraction step in which an extracted oil, which includes saturates, mono-aromatics, di-aromatics, tri-aromatics, poly-aromatics and a heptane insoluble component, is obtained by subjecting the heavy oil to a solvent extraction process using a solvent; and performing a hydrorefining step in which a hydrorefined oil is obtained by subjecting the obtained extracted oil to a hydrogenation process in the presence of hydrogen and a catalyst; continuously maintaining the poly-aromatics concentration within the range of 26.8 wt % to 40.2 wt % and a ratio of the heptane insoluble concentration to the poly-aromatics concentration within the range of 0.140 to 0.152 in the extracted oil obtained by the solvent extraction step which maintains a deasphalted oil extraction rate within the range of 55 to 85% by means of an NIR analyzer or an NMR analyzer as the index of the concentration of heptane-insoluble components in the extracted oil; based on correlation between the concentration of the heptane-insoluble components and the concentration of the poly-aromatics in the extracted oil, which is obtained in advance, comparing the detected poly-aromatics concentrations with a predetermined value of the poly-aromatic concentration; and according to the comparing result, continually controlling at least one of the extraction conditions selected from the extraction temperature and the flow rate of at least one of the solvent and the heavy oil in the solvent extraction step; and further continually controlling refining conditions of the hydrogenation refining step, thus producing a hydrorefined oil having a target concentration of the heptane-insoluble components.