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Author (up) Pedrouso, A.; Correa-Galeote, D.; Maza-Marquez, P.; Juarez-Jimenez, B.; Gonzalez-Lopez, J.; Rodelas, B.; Campos, J.L.; Mosquera-Corral, A.; del Rio, A.V..
Title Understanding the microbial trends in a nitritation reactor fed with primary settled municipal wastewater Type
Year 2021 Publication Separation And Purification Technology Abbreviated Journal Sep. Purif. Technol.
Volume 256 Issue Pages 117828
Keywords Autotrophic nitrogen removal; Free nitrous acid; Low temperature; Mainstream; Nitrite oxidation inhibition
Abstract Partial nitritation was pointed out as the key step to implement the autotrophic nitrogen removal processes at low temperature. This study investigated the initiation and maintenance of a nitritation process with simultaneous COD removal in a sequencing batch reactor (SBR) run at 15 degrees C and fed with primary settled urban wastewater characterized by 42 +/- 10 mg TOC/L and 45 +/- 4 mg NH4+-N/L. A nitrite accumulation ratio of nearly 100% was observed and the long-term (354 days) process stability was successfully maintained despite the municipal wastewater composition fluctuations. The absence of nitrite oxidizing bacteria (NOB) activity was attributed to the free nitrous acid (FNA) in-situ accumulated at high levels (0.02-0.20 mg HNO2-N/L). Despite nitrate production was not observed, the quantification of bacterial groups indicated that NOB were present in the SBR sludge throughout the entire operational period. Ammonium oxidizing bacteria (AOB) abundance and community structure were significantly influenced by the organic matter present in the feeding. Average organic matter removal efficiencies of 80% were obtained without observing any detrimental effect over the nitritation process performance, due to the functional redundancy within both the chemoheterotrophic and AOB communities.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1383-5866 ISBN Medium
Area Expedition Conference
Notes WOS:000675460300011 Approved
Call Number UAI @ alexi.delcanto @ Serial 1441
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Author (up) Pedrouso, A.; Morales, N.; Rodelas, B.; Correa-Galeote, D.; del Rio, A.V.; Campos, J.L.; Vazquez-Padin, J.; Mosquera-Corral, A.
Title Rapid start-up and stable maintenance of the mainstream nitritation process based on the accumulation of free nitrous acid in a pilot-scale two-stage nitritation-anammox system Type
Year 2023 Publication Separation And Purification Technology Abbreviated Journal Sep. Purif. Technol.
Volume 317 Issue Pages 123851
Keywords Ammonium oxidising bacteria (AOB); Anammox; Municipal wastewater treatment; Nitrite oxidising bacteria (NOB) suppression; PN; AMX pilot plant
Abstract Two-stage partial nitritation (PN) and anammox (AMX) systems showed promising results for applying auto-trophic nitrogen removal under mainstream conditions. In this study, a pilot-scale (600 L per reactor) two-stage PN/AMX system was installed in a municipal wastewater treatment plant (WWTP) provided with a high-rate activated sludge (HRAS) system for organic carbon removal. The PN/AMX system was operated without tem-perature control (ranging from 11 to 28 degrees C) and was subjected to the same variations in wastewater charac-teristics as the WWTP (22 to 63 mg NH4+- N/L). The developed strategy is simple, does not require the addition of chemicals and is characterised by short start-up periods. The PN process was established by applying a high hydraulic load and maintained by in situ accumulated free nitrous acid (FNA) of 0.015-0.2 mg HNO2-N/L. Based on pH value, a controlled aeration strategy was applied to achieve the target nitrite to ammonium ratio in the effluent (1.1 g NO2--N/g NH4+-N) to feed the AMX reactor. Although NOB were not fully washed out from the system, nitrite accumulation remained (>99 %) stable with no evidence of NOB activity. In the AMX reactor, an overall nitrogen removal efficiency of 80 % was achieved. Regarding effluent quality, 12 +/- 3 mg TN/L was obtained, but 5 mg NO3--N/L was already in the HRAS effluent. The relative abundance of NOB showed a strong negative correlation with the FNA concentration, providing a good strategy for establishing PN under main-stream conditions.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1383-5866 ISBN Medium
Area Expedition Conference
Notes WOS:001007409900001 Approved
Call Number UAI @ alexi.delcanto @ Serial 1821
Permanent link to this record