Evaluation of the operational status of an extended aeration activated sludge reactor through measurement of COD and nitrogen fractionation

  • Jumara del Carmen Males Álvarez Universidad Politécnica Salesiana - Ecuador
  • Jorge Eduardo Guerrero Aguirre Universidad Politécnica Salesiana - Ecuador
  • Renato Gabriel Sánchez Proaño Universidad Politécnica Salesiana - Ecuador
Keywords: Activated sludge age; Quitumbe WWTP; nitrification-denitrification.


The rapid population growth in the southern part of Quito, driven by the pursuit of material prosperity, has increased the production of wastewater, leading to discharges into water bodies and impacting water quality. In this context, characterizing wastewater is crucial for reliable operational decisions. This research evaluates the Quitumbe Wastewater Treatment Plant's bioreactor in relation to the fractionation of COD and nitrogen, considering the sludge age as a controlled variable. Wastewater samples were collected in March at the inlet and outlet points of the bioreactor, and a physicochemical method was used for COD fractionation. The results indicate a predominance of slowly biodegradable COD (XS) and removal rates of 95% for biodegradable COD and 93% for ammonia nitrogen, demonstrating biodegradation capacity. Incomplete nitrification was confirmed, along with a cellular retention time of 20 days. This study provides a solid foundation for improving the operational management of the Quitumbe Wastewater Treatment Plant.


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Author Biographies

Jumara del Carmen Males Álvarez, Universidad Politécnica Salesiana - Ecuador

Environmental Engineer from Salesian Polytechnic University.

Jorge Eduardo Guerrero Aguirre, Universidad Politécnica Salesiana - Ecuador

Environmental Engineer from Salesian Polytechnic University.

Renato Gabriel Sánchez Proaño, Universidad Politécnica Salesiana - Ecuador

Ph.D. in Collective Health, Environment, and Society from Simon Bolivar Andean University (UASB). Master's degree in Ecological Economics from the Latin American Faculty of Social Sciences (FLACSO). Environmental Engineer from National Polytechnic School of Ecuador (EPN) and a professor of Wastewater Treatment and Environmental Economics at the Salesian Polytechnic University.


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How to Cite
Males Álvarez, J. del C., Guerrero Aguirre, J. E., & Sánchez Proaño, R. G. (2023). Evaluation of the operational status of an extended aeration activated sludge reactor through measurement of COD and nitrogen fractionation. Religación, 8(37), e2301090. https://doi.org/10.46652/rgn.v8i37.1090