COD fraction analysis of anaerobic digester supernatant and piggery wastewater, using respirometric method

When operating an activated sludge model (ASM), organic matters among input data criteria including pH, temperature, sludge retention time, and many more, can be categorized to its own characteristics. Such category includes chemical oxygen demand (COD) and biochemical oxygen demand. However, these are not likely to represent benchmark criteria meeting the conditions required by ASM. In this study, experimenting piggery wastewater and an anaerobic digester supernatant from municipal wastewater treatment plants (MWTPs) with the use of the microbial respirometric method, the true categories for organic matters were implemented and assessed for the requirements of ASM. It was found that piggery wastewater was categorized with biodegradable organic matters with high content of slowly biodegradable COD, while anaerobic digester supernatant was mostly composed of non-biodegradable organic matters in high content of inert COD. When the COD fraction ratio discovered in this study is applied to an ASM for an accurate monitoring of a treating process of piggery wastewater and anaerobic digester supernatant, the findings could make a useful database in designing a biological treatment process and operating it in MWTP.