Digested sewage treatment using membrane-based process at different hydraulic retention times

Performance and Microbial Diversity in a Low-Energy ANF-WDSRBC System for the Post-Treatment of Decentralized Domestic Wastewater

“…The nitrite concentration was not accumulated, indicating that autotrophic denitrification might occur in the inner biofilm of the WDSRBC system [34,35]. The average TN removal efficiency in the ANF-WDSRBC system was 54.5% ± 3.9% (Table 2), which was similar to previous reports for AT-MBR system treating digested domestic wastewater [7]. The reduction of TN might be attributed to the denitrifier in the ANF.…”

“…Remarkably, different system configurations entailed variations of system performance. Gao et al [7] used the AT-MBR system to treat digested domestic wastewater with a total HRT of 8 h, reaching 87% of COD removal, 91% of NH 4 + -N removal, and 58% of TN removal. Even though the AT-MBR system found to have the best performance among these systems, the energy consumption of the AT-MBR system was significantly higher than others.…”

“…The wool-felt carriers were suitable for deploying high biomass and reducing washout of biomass. Without mechanical aeration devices in the oxic unit for improving oxygen transfer capacity and nitrification, the WDSRBC units are more energy-efficient than traditional RBC, MBR [7], and aeration filter [10] due to water-dropping gravity rotation.…”

“…It was reported that aerated filters [10], water-dropping aeration submerged biofilm reactor (WDABR) [4], aerobic membrane bioreactor (MBR) [6,7], stabilization ponds [11], and constructed wetlands (CW) [12,13] had been applied in decentralized domestic wastewater treatment. Nevertheless, there still have many challenges, such as high energy consumption in aerobic systems, low organic load rate, flow clogging of constructed wetlands and high land footprint of stabilization ponds existed during the whole process.…”

“…That may be attributed to the energy recovery and low sludge production in anaerobic bioreactors [1][2][3]. Despite of these advantages, anaerobic techniques are not widely adopted due to the lack of nitrogen removal capability [4][5][6][7]. Even though nitrogen is one of the important nutrients for agriculture and landscaping irrigation reuse [8], nitrogen also plays a major role in oxygen depletion and eutrophication in the receiving water bodies [9].…”