Digested blackwater treatment in a partial nitritation-anammox reactor under repeated starvation and reactivation periods. (20th January 2020)

• Record Type: Journal Article
• Authors: Pedrouso, Alba; Tocco, Giaime; Val del Río, Angeles; Carucci, Alessandra; Morales, Nicolás; Campos, Jose Luis; Milia, Stefano; Mosquera-Corral, Anuska
• Is Part Of: Journal of cleaner production. Volume 244(2020)
• Publication Date: 2020-01-20
• Subjects: Anammox -- Blackwater -- Decentralized systems -- Nitritation -- Starvation -- Wastewater source separation; Factory and trade waste -- Management -- Periodicals; Manufactures -- Environmental aspects -- Periodicals; Déchets industriels -- Gestion -- Périodiques; Usines -- Aspect de l'environnement -- Périodiques; 628.5
• DOI: 10.1016/j.jclepro.2019.118733
• Languages: English
• ISSNs: 0959-6526

Abstract

Abstract: Wastewater source-separation and on-site treatment systems face severe problems in wastewater availability. Therefore, the effect of repeated short-term starvation and reactivation periods on a partial nitritation-anammox (PN/AMX) based processes were assessed treating digested blackwater at room temperature. Two sequencing batch reactors (SBR) were operated, one of them during 24 h/day the whole week (SBR-C, which served as control) and the other with repeated starvation/reactivation periods during the nights and the weekends (SBR-D), using simulated blackwater (300 mg N/L and 200 mg COD/L) as substrate. Results showed no remarkable differences in overall processes performance between both reactors, achieving total nitrogen removal efficiencies (NRE) around 90%. Furthermore, no significant variations were measured in specific activities, except for the aerobic heterotrophic one that was lower in SBR-D, presumably due to the exposure to anoxic conditions. Then, the technical feasibility of applying the PN/AMX system to treat real blackwater produced in an office building during working hours was successfully proved in a third reactor (SBR-R), with the same starvation/reactivation periods tested in SBR-D. Despite the low temperature, ranging from 14 to 21 °C, total NRE up to 95% and total nitrogen concentration in the effluent lower than 10 mg N/L were achieved. Moreover, the PN/AMX process performance was immediately recovered after a long starvation period of 15 days (simulating holidays). Results proved for the first time the feasibility and long-term stability (100 days) of applying the PN/AMX processes for the treatment (and potential reuse) of blackwater in a decentralized system where wastewater is not always available. Graphical abstract: Image 1 Highlights: Blackwater treated by partial nitritation/anammox process with night/weekends stops. Stable nitrogen removal of 95% was maintained at low temperature (14–21 °C). The stops no affected the ammonium oxidizing and anammox bacterial activities. The starvation periods significantly decreased the aerobic heterotrophic activity. Achieved effluent concentration <10 mg N/L allows the water discharge or reuse.