Microwave-Enhanced Advanced Oxidation Treatment of Lipids and Food Wastes
Fats, oils, and grease (FOG) and source separated organics (SSO) were treated with the microwave-enhanced advanced oxidation process (MW-AOP) at 90 and 110 °C, with varying amounts of hydrogen peroxide dosages. The treatment efficiency, in terms of soluble substrates and volatile fatty acids (VFA), increased with an increase in both temperature hydrogen peroxide dosages. Fatty acids and compounds with carbonyl group and/or hydroxyl group in both initial and treated FOG samples were identified by gas chromatography-mass spectrometry. MW-AOP treatment temperatures and hydrogen peroxide dosages dictated the formation of degradation products. The degradation followed peroxidation mechanism to produce lower molecular weight substrates such as short chain fatty acids which would be less inhibitory to microbes. After the MW-AOP treatment, both SSO and FOG comprised of more soluble and low molecular weight compounds. These compounds included VFA and nutrients that would be readily available for bacterial or plant uptake.
KeywordsMW-AOP treatment Source separated organics Fats Oils and grease
Technical help provided by Indre Tunile, Sam Khalifa, and Nadia Langenberg is acknowledged.
The study receives a research funding partially by the Agri-tech Innovation Challenge, the BC Ministry of Agriculture, and the BC Innovation Council.
- APHA. (2012). Standard Methods for the Examination of Water and Wastewater (22nd ed.). Washington, DC: American Public Health Association.Google Scholar
- Goldstein, N. (2005). Source separated organics as feedstock for digesters. Biocycle, 46, 8.Google Scholar
- Hrudey, S. E. (1981). Activated sludge response to emulsified lipid loading. Water Research, 29, 525–533.Google Scholar
- Kilduff, J. E. ed. (2000). Hazardous and Industrial Waste, Proceedings, 32nd Mid-Atlantic Conference. CRC Press.Google Scholar
- Lemus, G. R., & Lau, A. K. (2002). Biodegradation of lipidic compounds in synthetic food wastes during composting. Canadian Biosystems Engineering, 44, 6.33–6.39.Google Scholar
- Lo, K. V., Liao, P. H., & Srinivasan, A. (2016). Continuous‐flow microwave enhanced oxidation process for treating sewage sludge. Canadian Journal of Chemical Engineering, 94(7), 1285–1294.Google Scholar
- Lo, K. V., Ning, R., de Oliveira, C. K. Y., De Zetter, M., Srinivasan, A., & Liao, P. H. (2017). Application of microwave oxidation process for sewage sludge treatment in a continuous-flow system. Journal of Environmental Engineering, 143(9). https://doi.org/10.1061/(ASCE)EE.1943-7870.0001247.
- Peil, A. L., & Gaudy, A. F. (1971). Kinetic constants for aerobic growth of microbial populations selected with various single compounds and with municipal wastes as substrates. Applied Microbiology, 21, 253–256.Google Scholar
- Spencer, R. (2010). High solids anaerobic digestion of source separated organics. BioCycle, 51, 8.Google Scholar
- Srinivasan, A., Viraraghavan, T., & Ng, W. K. T. (2012). Coalescence/filtration of an oil-in-water emulsion in an immobilized Mucor rouxii biomass bed. Separation Science and Technology, 7(16), 2241–2249.Google Scholar
- Wiley, J.S. (1957). Progress report on high-rate composting studies (pp. 596–603). In 12th Purdue Industrial Waste Conference Proceedings, Chelsea: Ann Arbor Press Inc.Google Scholar