Banca de DEFESA: MARCIO LUCIANO FERREIRA DE SA FILHO

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : MARCIO LUCIANO FERREIRA DE SA FILHO
DATE: 24/01/2022
TIME: 14:00
LOCAL: Online – Plataforma Google Meet (https://meet.google.com/xhr-rmgo-kwr)
TITLE:

USE OF MICROALGAE IN NITRATE REMOVAL IN WATER CONTAMINATED UNDERGROUND

KEY WORDS:

Biological denitrification, Nitrate-contaminated water, Scenedesmus sp., Nutrient removal.

PAGES: 68
BIG AREA: Engenharias
AREA: Engenharia Química
SUMMARY:

Nitrate is the most frequent contaminant in aquifers around the world. Anthropogenic activity
is the factor that most contributes to the contamination of water by the compost. Among the
sources of contamination, the inappropriate discharge of domestic wastewater is one of the most
relevant. In Brazil, there is an absence of sewage collection networks and the widespread use
of the septic tank and sink as an alternative is an aggravating factor in terms of groundwater
contamination. In this context, the present research aimed to evaluate the potential of using the
microalgae Scenedesmus sp. in the remediation of groundwater contaminated by nitrate, nitrite
and ammonia, considering the influence of nutritional and environmental factors in the process.
The experiments were set up in batch and semi-continuous mode, with surface and forced
aeration (0.5vvm), light intensities between 50 and 200 μmol m-2
s
-1
, pH range 8.0 - 8.5, nitrate
initial 50 - 400 mg/L, initial nitrite 0 - 16.8 mg/L, initial ammonia 0.0 - 9.0 mg/L, total
phosphate concentration 0 - 60 mg/L and cultivation time between 3 and 15 days. In batch
experiments, either with modified BG-11 culture medium or with real effluent, nitrate removals
reached up to 100% and total phosphate removal up to 94%, when carried out under forced
aeration. On the other hand, when the experiment was carried out in a semi-continuous way,
until the third cycle, an average of 87% of nitrate removal was obtained for a 20% of
bioreactor’s renewal, 79% of removal when the renewal was 40%, 57% removal for 60%
reactor refresh and 50% of the nitrate was removed when the bioreactor refresh was 80%. In
this manner, the volumetric replacement rates of 40 - 60% were those that showed greater
stability in the production of biomass, in the removal of nitrate and phosphate, also
demonstrating that low or very high replacement rates do not meet the required stability of the
system for the time adopted for each cycle. Thus, the results show the potential of Scenedesmus
sp. for remediation and adequacy of contaminated groundwater to current potability standards.

BANKING MEMBERS:
Presidente - 3081569 - CARLOS EDUARDO DE FARIAS SILVA
Externa ao Programa - 1272239 - DANIELE VITAL VICH
Interna - 1456420 - RENATA MARIA ROSAS GARCIA ALMEIDA