Statistical Modeling and Optimization of the Effective Parameters in Precipitation of Asphaltene from Vacuum Residue by Industrial Solvents

In this research, the possibility of asphaltene separation from the vacuum tower residue using the low cost industrial solvents such as 402, 404, 406, and 410 was investigated. In order to separate asphaltene the IP143/01 and ASTM D 3279-07 separation methods were utilized. In order to find the optimal state of asphaltene precipitation, Design of experiments software with three factors of residence time, the solvent-to-feed ratio and the volume percent of 406 solvent to the total solvent of 406 and 410 were used. The results showed that the effectiveness of each parameter in precipitating the asphaltene attributed to the ratio of solvent to feed, the ratio of solvent 406 to total solvent, and the residence time, respectively and there was a significant interaction between the basic parameters. The best asphaltene precipitation of 5.06% of 7.5% happens at the residence time of 36.97 hours, the ratio of solvent to feed of 35.95 ml/gr and the volume percent of 406 solvent to the total solvent of 27.20%. Asphaltene precipitation percentage for the optimal mixture of industrial solvents was 22.5% lower than the precipitated asphaltene from normal heptane solvent. However, according to the solvents price, industrial solvents (410 and 406) were approximately 50% cheaper than normal heptane, and hence on overall, there was a cost savings of more than 20%