Name: Laiza Cristina Ricatto da Silva
Type: MSc dissertation
Publication date: 04/03/2020
Advisor:

Name	Role
Valéria de Oliveira Fernandes	Advisor *

Examining board:

Name	Role
Maria do Carmo Pimentel Batitucci	Internal Alternate *
Paola Alfonsa Vieira Lo Monaco	External Examiner *
Paulo Wagnner Pereira Antunes	External Alternate *
Stéfano Zorzal de Almeida	Internal Examiner *
Valéria de Oliveira Fernandes	Advisor *

Summary: Swine is an important activity for the economy, being Brazil one of the largest pork producers in the world. However, such activity requires excessive use of freshwater to clean the nurseries, generating a large amount of wastewater, if without proper treatment, pollutes water bodies due to a large amount of nutrients, such as nitrogen (N) and phosphorus (P) that can be used by microalgae. Thus, the objective of this work was to cultivate the microalgae species Scenedesmus obliquus in swine wastewater (SW) as an alternative for the production of biofuels. The experiments were carried out on a laboratory scale, in the cultivation room of the Laboratory of Taxonomy and Ecology of Continental Algae of the Federal University of Espírito Santo. Three concentrations of SW (2.5%; 5%; 7.5%) diluted in deionized water were used. Several analyzes were carried out to monitor the growth of the strain during cultivation, in addition to physical-chemical analyzes of wastewater, characterization of biomass (proteins and lipids) and analysis of fatty acid methyl esters (FAME). In relation to growth, it was found that the best concentration of culture was observed in the treatments of 2.5%. Regarding biomass analyzes, the protein and lipid content decreased as the concentration of wastewater increased. However, the protein content found in the treatments was higher in relation to the lipid content. Despite this, in the FAME analysis several fatty acids that could be used in the production of biodiesel were found. The cultivation of S. obliquus demonstrated high efficiency in removing nutrients from wastewater, mitigating environmental impacts. In view of the results obtained, the cultivation of S. obliquus can be linked to the treatment of residues (bioremediation) and its biomass can be applied to the biofuel market.

Keywords: cultivation • biodiesel • microalgae • effluents • bioremediation