Banca de QUALIFICAÇÃO: ANA RACHEL MELO NASCIMENTO

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : ANA RACHEL MELO NASCIMENTO
DATE: 20/03/2020
TIME: 10:00
LOCAL: Auditório do Centro de Tecnologia
TITLE:

EVALUATION OF OXYGEN PRODUCTION AND CONSUMPTION RATES AND ITS INFLUENCE ON NUTRIENTS REMOVAL IN POLISHING PONDS

KEY WORDS:

UASB reactor. Polishing pond. Oxygen production rate. Nutrients Removal.

PAGES: 26
BIG AREA: Engenharias
AREA: Engenharia Sanitária
SUMMARY:

Wastewater treatment is a fundamental process for maintaining public health and promoting environmental health, constituting one of the pillars of basic sanitation. Among the wastewater treatment systems, the association of Upflow Anaerobic Sludge Blanket (UASB) and polishing ponds stands out. In this system, the polishing ponds, receiving the effluent already clarified by the reactor, have intense photosynthetic activity which results in high consumption of carbon dioxide (CO2) and high pH levels of the water, favoring the removal of ammoniacal nitrogen by desorption and allowing the precipitation of phosphorus salts. In polishing ponds (LP), the main responsible for the production of oxygen is the photosynthesis process carried out by the algae; while the main responsible for oxygen consumption is the process of oxidation of organic material by bacterias. The rate of oxygen production in LP has great importance for two reasons: the rate of production must be sufficient to supply the oxygen consumption in the pond to oxidize organic material and must also contribute to the increase of pH, enabling removal of nutrients from the wastewater. In this context, this research aims to investigate the influence of the rate of oxygen production and consumption in polishing ponds fed by effluent from UASB reactor in a sequential batch regime on nutrient removal processes. For this purpose, an experimental system will be developed, it will be composed by two UASB reactors with a useful volume of 25L operating with a hydraulic retention time of 6 hours and two polishing ponds with volume of 70L with variable hydraulic retention time (HDT). The efficiency evaluation of nutrients removal will be made for five different phases (HDT of 3,5,710 and 15 days) based on physical-chemical analyzes of Chemical Oxygen Demand (mg / L), ammoniacal nitrogen (mg / L), orthophosphates (mg / L), chlorophyll a (µg / L), alkalinity (mgCaCO3 / L) and turbidity (NTU) in raw sewage and in the effluent of the reactor and of the ponds. Additionally, the polishing ponds will have the dissolved oxygen (DO), pH and temperature parameters monitored continuously in the field through the use of portable equipment. Oxygen production rates of the pond will also be calculated from the DO readings in the material collected of the pond. To support the discussion of the results, when applicable, the data obtained will be systematized with descriptive statistics and analized by correlation tests (Pearson). To support the discussion of the results, when applicable, the data obtained will be systematized with descriptive statistics resources and analyzed using correlation tests (Pearson). At the end of the work, it is expected to observe algae proliferation in the lagoon, followed by a significant increase in the pH of the wastewater and a significant removal of nitrogen and reasonable phosphorus. In this way, it will be possible to detect a direct relationship between variations in OD, pH and nutrient removal rates.

BANKING MEMBERS:
Externa à Instituição - DAYANA MELO TORRES - IFRN
Interno - 1759924 - HELIO RODRIGUES DOS SANTOS
Presidente - 3057847 - SILVÂNIA LUCAS DOS SANTOS