Master's Dissertation
DOI
https://doi.org/10.11606/D.3.2019.tde-28112019-155818
Document
Author
Full name
Nara Alonso Salles
E-mail
Institute/School/College
Knowledge Area
Date of Defense
Published
São Paulo, 2019
Supervisor
Committee
Souza, Theo Syrto Octavio de (President)
Alem Sobrinho, Pedro
Moura, Rafael Brito de
Title in Portuguese
Cotratamento de esgoto sanitário e lixiviado de aterro sanitário em sistemas de lagoas aeradas e de lodos ativados: abordagem utilizando o ASM.
Keywords in Portuguese
ASM
ASM1. ASM3
Aterros sanitários
Esgotos sanitários
Lagoas aeróbias
Modelação matemática
Abstract in Portuguese
Title in English
Co-treatment of landfill leachate and sanitary sewage in aerated lagoon and activated sludge systems: under a mathematical modelling approach using ASM.
Keywords in English
ASM
ASM1
ASM3
Co-treatment
Landfill leachate
Mathematical modeling
Abstract in English
Due to environmental reasons, the treatment of leachate from landfills is necessary and the co-treatment of leachate with sanitary sewage is attractive, since the wastewater treatment system has operational amplitude, besides being a practical measure, since it allows the use of the existing wastewater treatment plant (WWTP) structure. However, due to the presence of inhibitory organic compounds, toxic substances and high concentrations of ammoniacal nitrogen in leachate, the efficiency of the wastewater treatment can be reduced. Therefore, the aim of this work was to evaluate the co-treatment of leachate and sanitary sewage under a mathematical modeling approach, to study scenarios and to predict situations to determine the best operational conditions and practices in the WWTP. Thus, the applicability of Activated Sludge Model No. 1 (ASM1) and No 3 (ASM 3) to aerated lagoons and activated sludge promoting the co-treatment was studied. The simulated scenarios consisted of leachate addition to the systems, in different concentrations, varying from 0 to 10% of leachate, and for each scenario were evaluated the heterotrophic and autotrophic biomass concentrations, COD consumption in different fractions, nitrification, oxygen and alkalinity consumption. Bench scale experiments using activated sludge were carried out to obtain kinetic parameters of nitrification, studying the co-treatment of leachate and sewage in proportions of 0 to 3% leachate to the sewage. The results showed that there was no limitation of nitrification in any of the applied scenarios and the results were used to support ASM1 calibration. The simulations results indicated that, before and after the model calibration of ASM1, both models were optimistic regarding the growth and time used by the biomass to adapt to the progressively aggressive scenarios offered by the greater presence of leachate. However, the models adequately represented the problems related to the maintenance of nitrification, due to the increased aeration requirement and alkalinity demand, and also predicted the damage to the treated effluent due to recalcitrant organic matter and, in the case of ASM3, also due to biodegradable organic matter that did not suffer hydrolysis. The models presented good applicability as a tool to qualitatively evaluate the behavior of WWTP when co-treating leachate; however, requires adjustments for optimization of real systems.