Banca de DEFESA: CARLA GISLAINE DE BARROS SCARP DOS REIS

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : CARLA GISLAINE DE BARROS SCARP DOS REIS
DATE: 12/07/2023
TIME: 14:00
LOCAL: Ambiente Virtual
TITLE:

EVALUATION OF NITROUS OXIDE EMISSION IN BIOLOGICAL REACTORS FOR THE COMBINED TREATMENT OF LANDFILL LEACHATE AND SANITARY SEWAGE

KEY WORDS:

Biological treatment, support media, MBBR (Moving Bed Biofilm Reactor), bioclastic granules.

PAGES: 98
BIG AREA: Ciências Agrárias
AREA: Engenharia Agrícola
SUMMARY:

Combined treatment is an alternative that has been implemented in some Wastewater Treatment Plants (WWTPs) in Brazil, aiming to treat landfill leachate along with sanitary sewage in existing treatment units. The combined treatment of leachate and sanitary sewage has proven to be a viable alternative, considering the minimization of adverse effects on the environment. Activated sludge treatment is a well-established technology that has been continuously improved to achieve better performance. To enhance biological processes' efficiency, new alternatives have been employed, such as the introduction of support media in the biological reactor. These support media can be granulated bioclastic materials, plastic biomedia, granular activated carbon, powdered activated carbon, among others. The biological removal of nutrients through nitrification and denitrification processes may result in the generation and emission of nitrous oxide (N2O). Thus, the present study aims to evaluate N2O emission in bench-scale biological reactors treating landfill leachate and sanitary sewage in a combined manner. Three reactors were operated in continuous mode, named: activated sludge reactor (ASR), moving bed biofilm reactor (MBBR), and activated sludge reactor with addition of bioclastic granulates (ASR-BG). Three leachate/sewage mixtures were evaluated volumetrically (0%, 0.5%, and 1%). For each condition, N2O emission and reactor performance were monitored. The experiment was divided according to the reactor feeding phases, initially fed only with synthetic sewage, and subsequently with the addition of leachate in proportions of 0.5% and 1.0% (v/v) in the feeding mixture. The removal efficiencies of organic matter, phosphorus, color, and turbidity were evaluated in the different analyzed phases. The addition of leachate in the feeding mixture did not cause significant impacts on the process, although it slightly reduced the removal efficiency of the parameters, it did not compromise the quality of the treated effluent. Regarding N2O emission, the reactors showed higher average concentrations when 1.0% (v/v) of leachate was added, with MBBR presenting the highest averages (3.19 mg N2O.d-1). ASR-BG exhibited slightly lower N2O emissions compared to the control (ASR), with values of 1.55 and 1.97 mg N2O.d-1, respectively, and it was not possible to conclude that the bioclastic granulates was decisive in reducing gas emissions.

COMMITTEE MEMBERS:
Presidente - 1759225 - ALEXANDRE LIOI NASCENTES
Interno - 2353141 - LEONARDO DUARTE BATISTA DA SILVA
Externo à Instituição - DIEGO MACEDO VENEU - UVA