Performance of a two-stage partial nitritation-anammox system treating the supernatant of a sludge anaerobic digester pretreated by a thermal hydrolysis process

Autor: Yves Lesty, Oscar Franchi, José Luis Campos, Jacques Dumais, José Ramón Vázquez-Padín, Anuska Mosquera-Corral, Marisol Belmonte, Daniel Valenzuela-Heredia, Camila Panatt, Ángeles Val del Río, Alba Pedrouso, Dafne Crutchik
Přispěvatelé: Universidade de Santiago de Compostela. Departamento de Enxeñaría Química, Universidade de Santiago de Compostela. Instituto Interdisciplinar de Tecnoloxías Ambientais (CRETUS)
Rok vydání: 2022
Předmět:
Zdroj: Minerva. Repositorio Institucional de la Universidad de Santiago de Compostela
instname
ISSN: 1385-8947
Popis: A two-stage system (partial nitritation (PN) and anammox processes) was used to remove nitrogen from the dewatering liquor originating from the thermal hydrolysis/anaerobic digestion (THP/AD) of municipal WWTP sludge. Two strategies were tested to start up the PN reactor: 1) maintaining a fixed hydraulic retention time (HRT) and increasing the ammonium loading rate (ALR) by decreasing the feeding dilution ratio and 2) feeding undiluted dewatering liquor and gradually decreasing the HRT. With diluted feeding, the reactor performance had destabilization episodes that were statistically correlated with the application of high specific ammonium (> 0.6 g NH4+-N/(g TSS·d)) and organic (> 0.7 g COD/(g TSS·d)) loading rates. The second strategy allowed stable PN reactor operation while treating ALR up to 4.8 g NH4+-N/(L·d) and demonstrating that dilution of THP/AD effluents is not required. The operating conditions promoted the presence of free nitrous acid levels (> 0.14 mg HNO2-N/L) inside the PN reactor that inhibited the proliferation of nitrite oxidizing bacteria. Batch activity tests showed that the inhibitory effects of organic compounds present in the THP/AD dewatering liquor on the ammonia oxidizing bacteria activity can be removed in the PN reactor. Thus, aerobic pretreatment would not be necessary when two-stage systems are used. The PN reactor effluent was successfully treated by an anammox reactor. An economic analysis showed that using two-stage systems is advantageous for treating THP/AD dewatering liquor. The implementation of an aerobic pre-treatment unit is recommended for WWTPs capacities higher than 5·105 inhabitants equivalent when one-stage systems are used This research was funded by the Chilean Government through the Projects ANID/FONDECYT/1200850 and CRHIAM Centre grant number ANID/FONDAP/15130015, by the Spanish Government through TREASURE [CTQ2017-83225-C2-1-R] and by the European Commission LIFE ZERO WASTE WATER [LIFE19ENV/ES/000631] projects. The authors from Universidade de Santiago de Compostela belong to CRETUS Strategic Partnership [ED431E 2018/01] and the Galician Competitive Research Group [GRC ED431C 2017/29]. All the Spanish programs are co-funded by FEDER (EU) 2023-07-15 SI
Databáze: OpenAIRE