Browsing by Author "Cerda, Ambar"

Now showing 1 - 2 of 2
  • No Thumbnail Available
    Item
    Coupling of the Feammox - Anammox pathways by using a sequential discontinuous bioreactor
    (2024) Gonzalez, Macarena; Cerda, Ambar; Rodriguez, Carolina; Serrano, Jennyfer; Leiva, Eduardo
    Treating nitrogenous compounds in wastewater is a contemporary challenge, prompting novel approaches for ammonium (NH4+) conversion to molecular nitrogen (N2). This study explores the classic anaerobic ammonium oxidation process (Anammox) coupled to the iron-dependent anaerobic ammonium oxidation process (Feammox) in a sequential discontinuous bioreactor (SBR) for NH4+ removal. Feammox and Anammox cultures were individually enriched and combined, optimizing the coupling, and identifying key variables influencing the enrichment process. Adding sodium acetate as a carbon source significantly reduces Fe3+ to Fe2+, indicating Feammox activity. Both Anammox and Feammox processes were successfully operated in SBRs, achieving efficient NH4+ removal (Anammox: 64.6 %; Feammox: 43.4 %). Combining these pathways in a single SBR enhances the NH4+ removal capacity of 50.8 %, improving Feammox efficiency. The Feammox process coupled with Anammox may generate the nitrite (NO2-) needed for Anammox. This research contributes to biotechnological advancements for sustainable nitrogenous compound treatment in SBRs.
  • No Thumbnail Available
    Item
    Feammox Bacterial Biofilms as an Alternative Biological Process for the Removal of Nitrogen from Agricultural Wastewater
    (2023) Cerda, Ambar; Gonzalez, Macarena; Rodriguez, Carolina; Serrano, Jennyfer; Leiva, Eduardo
    The excessive deposition of ammonium (reactive nitrogen) in the environment has led to losses of biodiversity and the eutrophication of ecosystems. Anthropogenic sources contribute twice the natural rate of terrestrial reactive nitrogen and provide about 45% of the total amount of it produced annually on Earth. Recently, a biological process that anaerobically metabolizes ammonium and facilitates iron reduction, termed Feammox, was discovered. The use of Feammox activity together with hollow fiber membrane bioreactors (HFMB), for which the latter are based on the formation of biofilms of bacterial communities, constitutes an efficient and sustainable method for the removal of ammonium from agriculturally derived wastewater. To implement the use of HFMB with Feammox activity, the formation of Feammox bacterial biofilms from wastewater sludge samples from a brewery was evaluated. The cultures were enriched with two different carbon sources, namely, sodium acetate and sodium bicarbonate; then, ferrous iron and ammonium concentrations, which were used as indicators of reactive nitrogen removal, were measured. The measurements revealed that the ammonium removal level reaches 20.4% when sodium acetate is used as carbon source. Moreover, an increase in the ferrous iron concentration of +Delta 84.6 mg/L was observed, indicating that Feammox activity had been generated. Biofilm formation was observed under Feammox conditions on the hollow fibers. These results showed that Feammox bacteria can form biofilms and efficiently remove ammonium from wastewater, constituting an essential feature with which to scale up the process to HFMBs. Overall, these results contribute to a better understanding of the Feammox process that can be used to implement these processes in agriculture and thus progress towards a more sustainable industry.