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Development of Sulfidogenic Sludge from Marine Sediments and Trichloroethylene Reduction in an Upflow Anaerobic Sludge Blanket Reactor
Published on: October 15, 2015
Microbial and functional resilience of a flocculent sludge-based partial denitrification-anammox system against cold
Ben Dai1, Jingzhou Zhou1, Zuobin Wang2
1State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.
Abstract:
The anammox process offers low-carbon, cost-effective solution for municipal wastewater treatment but faces challenges in non-tropical regions due to temperature sensitivity. This study investigated the nitrogen removal performance, microbial dynamics, and functional gene responses of an integrated partial denitrification-anammox (PDA) system using flocculent sludge under gradual and sudden temperature declines. The PDA process maintained stable nitrogen removal under gradual cooling, with effluent total nitrogen (TN) <1.5 mg/L, supported by stable NO2--supply despite a decreased NO3--to-NO2- conversion rate. Anammox activity progressively declined with temperature dropped, resulting in higher TN-concentration (reactor-concentration at 2 h, <2 mg/L at >20°C, ∼19 mg/L at 15 °C and ∼26 mg/L at 10 °C). Notably, anammox bacteria (AnAOB) remained functional despite reduced abundance. However, sudden cooling caused irreversible damage to AnAOB (cell may rupture), leading to NH4+-accumulation and system failure. Overall, these findings provide important insights into extending anammox technology to non-tropical wastewater treatment, enhancing its sustainable application.
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