(405f) Microwave Enhanced Advanced Oxidation Treatment of Anaerobic Digested Effluent

Microwave enhanced advanced oxidation treatment (MWAOP) is a thermo-chemical treatment process which has been used in several studies for effective treatment of organic wastes (Saha, M. 2018). In MWAOP, hydrogen peroxide oxidant is converted to hydroxyl radicals in presence of microwave heating. Hydroxyl radical is a much stronger oxidant than hydrogen peroxide. MWAOP oxidizes organic waste to final products such as volatile fatty acids (VFA) and carbon dioxide (CO₂) (Liao et al. 2007). This process disintegrates solids and helps to release nutrients from organic waste (Saha, M. 2018). In this study, MWAOP has been applied to treat anaerobic digested effluent. Anaerobic digestion is extensively used for renewable energy production from organic wastes. The anaerobic digested effluent is rich in nutrients and can be used as a potential source for nutrient recovery. This study was focused on investigating the effectiveness of MWAOP to treat anaerobic digested effluent to produce more suitable substrate for the subsequent nutrient recovery. The digested effluent was collected from a dairy farm. All experiments were performed in a batch scale microwave system of 2450 MHz. The digested effluent was treated at two different temperatures (90°C and 110°C) using MWAOP. The results showed that settleability of MWAOP treated digested effluent was improved and soluble COD was increased after the treatment. Hence, MWAOP treated digested effluent might improve the subsequent nutrient recovery process.

References

[1] Liao, P. H., Lo, K. V., Chan, W. I., & Wong, W. T. (2007). Sludge reduction and volatile fatty acid recovery using microwave advanced oxidation process. Journal of Environmental Science and Health Part A, 42(5), 633-639.

[2] Saha, M. (2018). Microwave enhanced advanced oxidation treatment of organic slurries (Master’s dissertation, University of British Columbia).