Shale oil recovery from oil shale sludge can reclaim secondary energy source and has drawn widespread attention in recent years. In this study, three oil recovery approaches, namely surfactant washing, solvent extraction, and the combination of the two procedures, were investigated to compare their oil removal capacities. Results showed that optimum conditions for surfactant washing were as follows: stirring rate 250 rpm, reaction temperature 80 °C, liquid-to-solid mass ratio 7:1, duration 30 min and surfactant solution concentration 6g/L. In case of solvent extraction, ethanol achieved the highest extraction yield, 89.53%, and petroleum ether (PE) performed with the shortest extraction time. Solvent extraction was more promising than surfactant washing in removing oil components. In the combined process, surfactant sodium dodecyl sulfate (SDS) washing and different solvent extractions contributed to each other’s oil removal capacity. GC-MS analysis showed that the extracted oil mainly contained saturates and 1-alkenes in the range of C11–C34, and that the previous surfactant washing could enhance the leaching of light hydrocarbons from oil shale sludge when using methyl ethyl ketone (MEK) and dichloromethane (DCM) extractions. The extracted oils could be recovered through distillation, which needed a hermetic apparatus to prevent the loss of oil components.
1. He, H. Oil sludge treatment in oil shale retorting process. Journal of Liaoning University of Petroleum & Chemical Technology, 2009, 29, 50–52 (in Chinese).
2. Wu, G., Zhang, G., Su, H. Research and application of processing technology for grounded oily sludge. Xinjiang Petroleum Science and Technology, 2007, 17, 24–26 (in Chinese).
3. Hu, G., Li, J., Zeng, G. Recent development in the treatment of oily sludge from petroleum industry: A review. J. Hazard. Mater., 2013, 261, 470–490.
http://dx.doi.org/10.1016/j.jhazmat.2013.07.069
4. Du, G., Huang, T. Study on the dehydration-drying of oily sludge from settling tank. Petroleum Processing and Petrochemicals, 2011, 42(9), 78–81 (in Chinese).
5. Zheng, L., Wang, D., Wang, X. Using chemical destabilization-dehydration method to treat high water-cut sludge. Sino-Global Energy, 2011, 16(9), 90–93 (in Chinese).
6. Wang, D., Sun, J., Li, Y. Study on process parameters of oily sludge washing. Chemical Engineering of Oil and Gas, 2008, 37, 249–252 (in Chinese).
7. Wang, D., Li, Y., Wang, Y., Sun, J. Study on process conditions of oil sludge washing and petroleum retrievement by thermo-chemical washing. Environmental Pollution and Control, 2008, 30(9), 39–42 (in Chinese).
8. Zhao, Y. Treatment of oily sludge in oil field with hot water washing. Journal of Liaoning Shihua University, 2011, 31, 14–17 (in Chinese).
9. Zhang, J., Xiang, W., Han, M., Li, M., Jiang, W. Review on chemical demulsification of crude oil emulsions. Oilfield Chemistry, 2005, 22, 283–288 (in Chinese).
10. Zhang, J., Li, J., Thring, R. W., Hu, X., Song, X. Oil recovery from refinery oily sludge via ultrasound and freeze /thaw. J. Hazard. Mater., 2012, 203–204, 195–203.
http://dx.doi.org/10.1016/j.jhazmat.2011.12.016
11. Zhou, L., Jiang, X., Liu, J. Characteristics of oily sludge combustion in circulating fluidized beds. J. Hazard. Mater., 2009, 170(1), 175–179.
http://dx.doi.org/10.1016/j.jhazmat.2009.04.109
12. Sun, B., Ma, B., Li, S., Wang, Q. Pyrolysis mechanism of oil shale sludge under liner heating temperature. Chemical Industry and Engineering Progress, 2013, 32(07), 1484–1488 (in Chinese).
13. Cui, B., Cui, F., Jing, G., Xu, S., Huo, W., Liu, S. Oxidation of oily sludge in supercritical water. J. Hazard. Mater., 2009, 165(1–3), 511–517.
http://dx.doi.org/10.1016/j.jhazmat.2008.10.008
14. Cui, B., Liu, S., Cui, F., Jing, G., Liu, X. Lumped kinetics for supercritical water oxidation of oily sludge. Process Saf. Environ., 2011, 89(3), 198–203.
http://dx.doi.org/10.1016/j.psep.2011.02.001
15. Zubaidy, E. A. H., Abouelnasr, D. M. Fuel recovery from waste oily sludge using solvent extraction. Process Saf. Environ., 2010, 88(5), 318–326.
http://dx.doi.org/10.1016/j.psep.2010.04.001
16. Zhou, G., Zhu, Y., Wei, X. GC/MS analyses of oil shale's CS2-NMP extract soluble fractions. Journal of Heilongjiang Institute of Science and Technology, 2006, 16, 390–392 (in Chinese).
17. Huang, X. Advance on technologies of oil shale solvent extraction. Modern Chemical Industry, 2012, 32, 12–15 (in Chinese).
18. Wu, P. Research on oil shale solvent extraction technology. Multi-Purpose Utilization of Mineral Resources, 2010, 5, 37–39 (in Chinese).
19. Andrade, P. F., Azevedo, T. F., Gimenez, I. F., Filho, A. G. S., Barreto, L. S. Conductive carbon-clay nanocomposites from petroleum oily sludge. J. Hazard. Mater., 2009, 167(1–3), 879–884.
http://dx.doi.org/10.1016/j.jhazmat.2009.01.070
20. Ma, Z., Gao, N., Xie, L., Li, A. Study of the fast pyrolysis of oilfield sludge with solid heat carrier in a rotary kiln for pyrolytic oil production. J. Anal. Appl. Pyrol., 2014, 105, 183–190.
http://dx.doi.org/10.1016/j.jaap.2013.11.003
21. Ramírez Restrepo, A., Gallo Ortiz, A. F., Hoyos Ossa, D. E., Peñuela Mesa, G. A. QuEChERS GC–MS validation and monitoring of pesticide residues in different foods in the tomato classification group. Food Chem., 2014, 158, 153–161.
http://dx.doi.org/10.1016/j.foodchem.2014.02.121
http://dx.doi.org/10.1016/j.arabjc.2011.06.007
