Statistical Optimization of Lipid Extraction from Wastewater Scum Sludge and Saponifiable Lipids Composition Analysis
Science Journal of Energy Engineering
Volume 5, Issue 2, April 2017, Pages: 48-57
Received: Mar. 31, 2017; Accepted: Apr. 11, 2017; Published: Oct. 18, 2017
Views 1539      Downloads 69
Samir N. Hag Ibrahim, Biology Department, Faculty of Science and Arts, Taibah University, Al-Ula, Saudi Arabia; Department of Environmental Science and Technology, Faculty of Science and Technology, Al Neelian University, Khartoum, Sudan
Article Tools
Follow on us
In the present study, Design of Experiment (DoE) as a statistical method was adopted for optimizing conditions for lipid extraction from scum sludge. Four different extraction variables were investigated: methanol to hexane ratio (%), solvent to sludge ratio (ml/g), temperature (°C), and extraction time (h). During the optimization process, saponifiable lipids (SLs) content of the extracted lipid was analyzed. Screening experiments revealed that methanol to hexane ratio (X1), solvents to sludge ratio (X2) and temperature (X3) showed a significant effect on Ylipid (p < 0.05). Lower methanol to hexane ratio and higher solvent to sludge ratio showed the highest positive effect on lipid yield (Ylipid). No significant effect on extraction time on Ylipid was observed. The positive relationship between lower methanol to hexane ratio and the amount of lipid extracted can be attributed to the presence of higher amounts of neutral lipids in scum sludge. According to Box-Behnken design and Response surface method (RSM), the maximum lipid extraction yield (Ylipid) predicted through numerical optimized conditions by the model for highest desirability (0.995) was 29.614% at methanol to hexane ratio (%) of 42%, solvent to sludge ratio (v/wt) of 51 ml/g, temperature at 87°C for extraction time of 6 hours. The FAMEs yield produced from ex-situ acid-catalyzed esterification/transesterification of the methanol-hexane co-solvent extracted lipid ranged between 7.9-9.3% (wt/wt) based on sludge weight. Fatty acid profile of FAMEs was found to be was found to be dominated by Oleic acid methyl ester (C18: 1) followed by methyl Palmitate (C16: 1) representing 39.4% and 24.3% of FAMEs composition respectively. The correlation analysis of extraction variables and FEMAs yield revealed that solvent to sludge ratio (ml/g) has the highest positive significant correlation with FAMEs yield (p-value < 0.05). However, methanol to hexane ratio (X1) and temperature (X3) were inversely correlated with FAMEs yield.
Scum Sludge, Lipid, Box-Behnken Design, Response Surface Method (RSM), FEMAs
To cite this article
Samir N. Hag Ibrahim, Statistical Optimization of Lipid Extraction from Wastewater Scum Sludge and Saponifiable Lipids Composition Analysis, Science Journal of Energy Engineering. Vol. 5, No. 2, 2017, pp. 48-57. doi: 10.11648/j.sjee.20170502.12
Copyright © 2017 Authors retain the copyright of this article.
This article is an open access article distributed under the Creative Commons Attribution License ( which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Morsy, Fatthy Mohamed, and Samir Hag Ibrahim. 2016. Concomitant hydrolysis of sucrose by the long half-life time yeast invertase and hydrogen production by the hydrogen overproducing Escherichia coli HD701. Energy 109: 412–419. doi: 10.1016/
Morsy, Fatthy Mohamed, Ismail Ahmed Ismail, and Samir Hag Ibrahim. 2016. A cost-effective, temperature dependent, control of H 2 production period by Escherichia coli and using waste culture to detoxify the carcinogenic Cr 6 þ. International Journal of Hydrogen Energy 41: 22775–22785. doi: 10.1016/j.ijhydene.2016.10.085.
Atabani, A. E., A. S. Silitonga, Irfan Anjum Badruddin, T. M. I. Mahlia, H. H. Masjuki, and S. Mekhilef. 2012. A comprehensive review on biodiesel as an alternative energy resource and its characteristics. Renewable and Sustainable Energy Reviews 16: 2070–2093. doi: 10.1016/j.rser.2012.01.003.
Dufreche, Stephen, R. Hernandez, T. French, D. Sparks, M. Zappi, and E. Alley. 2007. Extraction of lipids from municipal wastewater plant microorganisms for production of biodiesel. JAOCS, Journal of the American Oil Chemists’ Society 84: 181–187. doi: 10.1007/s11746-006-1022-4.
Leiva-Candia, D. E., S. Tsakona, N. Kopsahelis, I. L. Garcia, S. Papanikolaou, M. P. Dorado, and A. A. Koutinas. 2015. Biorefining of by-product streams from sunflower-based biodiesel production plants for integrated synthesis of microbial oil and value-added co-products. Bioresource Technology 190: 57–65. doi: 10.1016/j.biortech.2015.03.114.
Leiva-Candia, D. E., S. Tsakona, N. Kopsahelis, I. L. Garcia, S. Papanikolaou, M. P. Dorado, and A. A. Koutinas. 2014. The potential for agro-industrial waste utilization using oleaginous yeast for the production of biodiesel. Bioresource Technology 123: 33–42. doi:
Banković-Ilić, Ivana B., Ivan J. Stojković, Olivera S. Stamenković, Vlada B. Veljkovic, and Yung Tse Hung. 2014. Waste animal fats as feedstocks for biodiesel production. Renewable and Sustainable Energy Reviews 32: 238–254. doi: 10.1016/j.rser.2014.01.038.
Bharathiraja, B., M. Chakravarthy, R. Ranjith Kumar, D. Yuvaraj, J. Jayamuthunagai, R. Praveen Kumar, and S. Palani. 2014. Biodiesel production using chemical and biological methods - A review of process, catalyst, acyl acceptor, source and process variables. Renewable and Sustainable Energy Reviews 38: 368–382. doi: 10.1016/j.rser.2014.05.084.
Ingole, S P, and A U Kakde. 2012. Evaluation of various plant species for biodiesel production. Current Botany 3: 22–25.
Knothe, Gerhard. 2010. Biodiesel and renewable diesel: A comparison. Progress in Energy and Combustion Science 36: 364–373. doi: 10.1016/j.pecs.2009.11.004.
Leung, Dennis Y. C., Xuan Wu, and M. K. H. Leung. 2010. A review on biodiesel production using catalyzed transesterification. Applied Energy 87: 1083–1095. doi: 10.1016/j.apenergy.2009.10.006.
Demirbas, Ayhan. 2009. Progress and recent trends in biodiesel fuels. Energy Conversion and Management 50: 14–34. doi: 10.1016/j.enconman.2008.09.001.
Krawczyk, Tom. 1996. Biodiesel. Alternative fuel makes inroads but hurdles remain. Inform 7: 800–815.
Balat, Mustafa. 2011. Potential alternatives to edible oils for biodiesel production – A review of current work. Energy Conversion and Management 52: 1479–1492. doi: 10.1016/j.enconman.2010.10.011.
Bharathiraja, B, D Yogendran, R Ranjith Kumar, M Chakravarthy, and S Palani. 2014. Biofuels from sewage sludge-A review. International Journal of ChemTech Research 6: 974–4290.
Kargbo, Dm. 2010. Biodiesel production from municipal sewage sludges. Energy & Fuels 24: 2791–2794. doi: 10.1021/ef1001106.
Olkiewicz, Magdalena Anna. 2015. Production of Biodiesel From Sludge Generated in Municipal Sludge Generated in Municipal (Thesis). Rovira i Virgili University.
Revellame, Emmanuel, Rafael Hernandez, William French, William Holmes, Earl Alley, and Robert Callahan. 2011. Production of biodiesel from wet activated sludge. Journal of Chemical Technology and Biotechnology 86: 61–68. doi: 10.1002/jctb.2491.
Sheik, Abdul R., Emilie E. L. Muller, and Paul Wilmes. 2014. A hundred years of activated sludge: time for a rethink. Frontiers in Microbiology 5. Frontiers: 47. doi: 10.3389/fmicb.2014.00047.
Kargbo, David M. 2010. Biodiesel Production from Municipal Sewage Sludges. Energy & Fuels 24. American Chemical Society: 2791–2794. doi: 10.1021/ef1001106.
Mondala, Andro, Kaiwen Liang, Hossein Toghiani, Rafael Hernandez, and Todd French. 2009. Biodiesel production by in situ transesterification of municipal primary and secondary sludges. Bioresource Technology 100: 1203–1210. doi: 10.1016/j.biortech.2008.08.020.
Pokoo-Aikins, Grace, Aubrey Heath, Ray A. Mentzer, M. Sam Mannan, William J. Rogers, and Mahmoud M. El-Halwagi. 2010. A multi-criteria approach to screening alternatives for converting sewage sludge to biodiesel. Journal of Loss Prevention in the Process Industries 23: 412–420. doi: 10.1016/j.jlp.2010.01.005.
Boocock, David G. B., Samir K. Konar, Anna Leung, and Lang D. Ly. 1992. Fuels and chemicals from sewage sludge. Fuel 71: 1283–1289. doi: 10.1016/0016-2361(92)90055-S.
Siddiquee, Muhammad N., and Sohrab Rohani. 2011. Experimental analysis of lipid extraction and biodiesel production from wastewater sludge. Fuel Processing Technology 92: 2241–2251. doi: 10.1016/j.fuproc.2011.07.018.
Siddiquee, Muhammad N., and Sohrab Rohani. 2011. Lipid extraction and biodiesel production from municipal sewage sludges: A review. Renewable and Sustainable Energy Reviews 15: 1067–1072.
Girisha, Sirangala Thimappa, Krishnappa Ravikumar, and Venkatachalapathy Girish. 2014. Lipid extraction for biodiesel production from municipal sewage water sludge. European Journal of Experimental Biology 4: 242–249.
Mondala, Andro, Kaiwen Liang, Hossein Toghiani, Rafael Hernandez, and Todd French. 2009. Biodiesel production by in situ transesterification of municipal primary and secondary sludges. Bioresource Technology 100: 1203–1210. doi: 10.1016/j.biortech.2008.08.020.
Pastore, Carlo, Antonio Lopez, Vincenzo Lotito, and Giuseppe Mascolo. 2013. Biodiesel from dewatered wastewater sludge: A two-step process for a more advantageous production. Chemosphere 92: 667–673. doi: 10.1016/j.chemosphere.2013.03.046.
Olkiewicz, Magdalena, Natalia V. Plechkova, Azael Fabregat, Frank Stüber, Agustí Fortuny, Josep Font, and Christophe Bengoa. 2015. Efficient extraction of lipids from primary sewage sludge using ionic liquids for biodiesel production. Separation and Purification Technology 153: 118–125. doi: 10.1016/j.seppur.2015.08.038.
Olkiewicz, Magdalena, Martin Pablo Caporgno, Agustí Fortuny, Frank Stüber, Azael Fabregat, Josep Font, and Christophe Bengoa. 2014. Direct liquid-liquid extraction of lipid from municipal sewage sludge for biodiesel production. Fuel Processing Technology 128: 331–338. doi: 10.1016/j.fuproc.2014.07.041.
Qi, Juanjuan, Fenfen Zhu, Xiang Wei, Luyao Zhao, Yiqun Xiong, Xuemin Wu, and Fawei Yan. 2015. Comparison of biodiesel production from sewage sludge obtained from the A2/O and MBR processes by in situ transesterification. Waste Management 49: 212–220. doi: 10.1016/j.wasman.2016.01.029.
Kumar, Manish, Pooja Ghosh, Khushboo Khosla, and Indu Shekhar Thakur. 2016. Biodiesel production from municipal secondary sludge. Bioresource Technology 216: 165–171. doi: 10.1016/j.biortech.2016.05.078.
Bi, Chong hao, Min Min, Yong Nie, Qing long Xie, Qian Lu, Xiang yuan Deng, Erik Anderson, Dong Li, Paul Chen, and Roger Ruan. 2015. Process development for scum to biodiesel conversion. Bioresource Technology 185: 185–193. doi: 10.1016/j.biortech.2015.01.081.
di Bitonto, Luigi, Antonio Lopez, Giuseppe Mascolo, Giuseppe Mininni, and Carlo Pastore. 2016. Efficient solvent-less separation of lipids from municipal wet sewage scum and their sustainable conversion into biodiesel. Renewable Energy 90: 55–61. doi: 10.1016/j.renene.2015.12.049.
Wang, Yi, Sha Feng, Xiaojuan Bai, Jingchan Zhao, and Siqing Xia. 2016. Scum sludge as a potential feedstock for biodiesel production from wastewater treatment plants. Waste Management 47: 91–97. doi: 10.1016/j.wasman.2015.06.036.
Chipasa, K. B., and K. Mędrzycka. 2006. Behavior of lipids in biological wastewater treatment processes. Journal of Industrial Microbiology & Biotechnology 33: 635–645. doi: 10.1007/s10295-006-0099-y.
Wiltsee, George. 1998. Waste grease resource in 30 US metropolitan areas. In The Proceedings of Bioenergy 98 Conference, Wisconsin, 956–963.
Imandi, Sarat Babu, Veera Venkata Ratnam Bandaru, Subba Rao Somalanka, Sita Ramalakshmi Bandaru, and Hanumantha Rao Garapati. 2008. Application of statistical experimental designs for the optimization of medium constituents for the production of citric acid from pineapple waste. Bioresource Technology 99: 4445–4450. doi: 10.1016/j.biortech.2007.08.071.
Long, Chuannan, Jingjing Cui, Zuotao Liu, Yuntao Liu, Minnan Long, and Zhong Hu. 2010. Statistical optimization of fermentative hydrogen production from xylose by newly isolated Enterobacter sp. CN1. International Journal of Hydrogen Energy 35: 6657–6664. doi: 10.1016/j.ijhydene.2010.04.094.
Annadurai, G., S. Mathalai Balan, and T. Murugesan. 1999. Box-Behnken design in the development of optimized complex medium for phenol degradation using Pseudomonas putida (NICM 2174). Bioprocess Engineering 21. Springer-Verlag: 415–421. doi: 10.1007/PL00009082.
Francis, Febe, Abdulhameed Sabu, K. Madhavan Nampoothiri, Sumitra Ramachandran, Sanjoy Ghosh, George Szakacs, and Ashok Pandey. 2003. Use of response surface methodology for optimizing process parameters for the production of α-amylase by Aspergillus oryzae. Biochemical Engineering Journal 15: 107–115. doi: 10.1016/S1369-703X(02)00192-4.
Varrone, Cristiano, Barbara Giussani, Giulio Izzo, Giulia Massini, Antonella Marone, Antonella Signorini, and Aijie Wang. 2012. Statistical optimization of biohydrogen and ethanol production from crude glycerol by microbial mixed culture. International Journal of Hydrogen Energy 37: 16479–16488. doi: 10.1016/j.ijhydene.2012.02.106.
Science Publishing Group
1 Rockefeller Plaza,
10th and 11th Floors,
New York, NY 10020
Tel: (001)347-983-5186