Banca de DEFESA: JOSIVALDO RODRIGUES SÁTIRO

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
STUDENT : JOSIVALDO RODRIGUES SÁTIRO
DATE: 30/07/2021
TIME: 09:00
LOCAL: Auditório Pós-Graduação Engenharia Civil - CTG - UFPE
TITLE:

FACTORS THAT INFLUENCE MICROALGAE BIOFLOCULATION IN HIGH RATE PONDS WITH SANITARY SEWAGE

KEY WORDS:

Microalgae-bacteria consortium; Lipids; Removal of nutrients; Sedimentability; Sewage treatment.

PAGES: 100
BIG AREA: Engenharias
AREA: Engenharia Civil
SUMMARY:

The deterioration of water bodies resulting from the release of untreated sewage can be mitigated with the use of biological treatment processes and, thus, reduce the concentration of organic matter, nutrients, among other pollutants. Among the available processes, systems that use microalgae-bacteria are considered promising and sustainable alternatives, as they do not require artificial aeration and because of the possibility of producing products with added value, such as lipids, which can be used for the production of biofuels. However, the separation of dispersed biomass can be a limiting factor for the application of these systems and the formation of a dense biomass becomes an important requirement. In this context, the main objective of this work was to investigate the effect of activated sludge inoculation on the formation and stability of microalgae-bacterial aggregate on sedimentability, lipid production and sewage treatment in high rate lagoons in pilot scale. As a starting strategy, three lagoons were operated: LAT 1, LAT 2 and LAT 3, with heights of 0.30 m, 0.30 m and 0.50 m, respectively. LAT 1 was used as a control without inoculation of activated sludge, while LAT 2 and LAT 3 were inoculated with activated sludge with a concentration of 0.5 g/L of SSV. These were operated in two consecutive batches to obtain the aggregate and were sequentially operated in a continuous regime, with a hydraulic detention time of 4 days. Regarding the results, it was observed the stabilization of the biomass and stationary phase of the system after 20 days of operation in the continuous phase, mainly in lakes LAT 2 and LAT 3. LAT 1, LAT 2 and LAT 3 achieved total nitrogen removal from 82.2%, 76.6% and 53.4% and organic matter removal evaluated in COD of 90.33%, 85.22% and 97.33%, respectively. Regarding the sedimentability of biomass, in LAT 2 and LAT 3, an increase in SSV and flocculation efficiency was observed as the microalgae-bacteria aggregate system stabilized, that is, from day 20 of operation with continuous feeding, as mentioned above, thus obtaining SSV values in mg/L of 170.0 and 157.5, in that order. The LAT 1 biomass characteristics varied throughout the operational phase, being related to the seasonality and dilution of the effluent during the operation period. Assessing the flocculation efficiency, it was found that the lakes that were inoculated with activated sludge, being LAT 2 and LAT 3, obtained higher values of 90.6% and 93.4%, indicating good biomass sedimentation and relevance in the use of inoculum and two sequential batches at the start of the lagoons. In this perspective, this study with microalgae-bacteria aggregate showed results for the removal of organic matter and high nutrients, especially in LAT 2, with a water depth of 0.30 m, demonstrating the relevance of starting the systems through batches sequential use of the inoculum and water depth for the stability of the systems, as well as in the formation and harvesting of biomass to generate value-added products.

BANKING MEMBERS:
Externo à Instituição - ANTONIO JOÃO CARVALHO DE ALBUQUERQUE
Interna - 3133998 - BRUNA SCANDOLARA MAGNUS
Presidente - 2130916 - MARIA DE LOURDES FLORENCIO DOS SANTOS