High-rate anaerobic treatment system for solid/lipid-rich wastewater using anaerobic baffled reactor with scum recovery

• Published in: Bioresource technology Vol. 263; pp. 145 - 152
• Main Authors: Fujihira, Takuya, Seo, Shogo, Yamaguchi, Takashi, Hatamoto, Masashi, Tanikawa, Daisuke
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.09.2018
• Subjects: Anaerobic baffled reactor; Down-flow hanging sponge reactor; High-rate anaerobic treatment system; Scum recovery; Solid/lipid-rich wastewater; Solid/lipid-rich wastewater; Scum recovery; Down-flow hanging sponge reactor; Anaerobic baffled reactor; High-rate anaerobic treatment system
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2018.04.091

[Display omitted] •In the ABR, >90% of the inlet COD was removed and >70% of the inlet COD converted to energy.•ABR-DHS system achieved high-rate wastewater treatment system.•Biogas contributes to the scum formation.•Scum recovery contributes to achieving high-rate anaerobic treatment. A laboratory scale experiment was conducted to investigate the treatment of solid/lipid-rich wastewater with an anaerobic baffled reactor (ABR) and a down-flow hanging sponge (DHS) reactor. In this study, experimental periods were divided into three phases to explore efficient treatment of solids and lipids in wastewater. In ABR, >90% of the influent chemical oxygen demand (COD) was removed and >70% of the removed COD was converted to methane under steady-state conditions during each phase. During this period, >4.5 kg COD m−3 d−1 was achieved on an average in Phases 1 and 3. Biogas contributed to scum formation, and the scum was categorized into lipid-rich and sludge-containing types, which have energy potentials of 53.4 and 212 kcal/kg-wet weight, respectively. Therefore, by recovering solids and lipids, which formed persistent scum, ABR can be applied as a high-rate treatment for solid/lipid-rich wastewater.