Made available in DSpace on 2017-07-24T19:37:54Z (GMT). No. of bitstreams: 1 Tanna Fiuza.pdf: 3748455 bytes, checksum: d93bc838fb106338baeda5d66a782405 (MD5) Previous issue date: 2016-02-17 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Due of search for lower cost inorganic pigments, aiming enable their application in large scale, the utilization of residues containing elements of interest in synthesis was viewed as an interesting alternative. Thus, the main aim of this research was find an application for scum generated from reactor of anaerobic treatment of domestic effluents, since this residue has no application until now. Therefore, ashes of scum generated from anaerobic treatment of domestic effluents were submitted to acid and thermal treatments, aiming pigments with more intense color. All the samples obtained are composed by Al2O3, Fe2O3 e Ca9Al(PO4)7. The samples treated thermally to 950 and 1000 °C presented excellent results for enamel ceramic pieces, for coloration of polymethylmethacrylate (PMMA) and as pigment for water-based paints. The samples obtained to 1100 °C and the synthetic samples presented good results for enamel ceramic pieces, but not for PMMA and paint, in this case milling is necessary. The residue of acid treatment is rich in Si and Ca, therefore, this sample presents potential to future researches. / Diante da busca por pigmentos inorgânicos de menor custo, visando viabilizar sua aplicação em larga escala, a utilização de resíduos contendo elementos de interesse nas sínteses se mostrou uma alternativa interessante. Assim, o objetivo principal deste trabalho foi buscar uma aplicação para a escuma gerada em reator anaeróbico de tratamento de efluentes domésticos, resíduo este sem utilização até o momento. Para tanto, cinzas da escuma gerada em reator anaeróbico de tratamento de efluentes domésticos foram submetidas a tratamento ácido e térmico, visando a purificação e obtenção de um material com coloração mais intensa e mais apropriada para a utilização como pigmentos. A partir das análises realizadas foi verificado que o tratamento adotado foi eficaz, obtendo-se amostras com coloração laranja/vermelha intensa, compostas por Al2O3, Fe2O3 e Ca9Al(PO4)7. As amostras tratadas a 950 e 1000 °C apresentaram bons resultados na esmaltação de peças cerâmicas, na coloração de poli(metacrilato de metila) (PMMA) e como pigmento para tinta à base de água. As amostras obtidas a 1100 °C e a amostra sintética (preparada com composição similar às amostras obtidas a partir da escuma), apresentaram bons resultados na esmaltação de peças cerâmicas, mas necessitam de moagem para a aplicação no PMMA e na tinta. O resíduo do tratamento ácido é rico em cálcio e silício, apresentando potencial para futuras pesquisas.

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En raison de leur importante capacité de réponse aux changements environnementaux, les producteurs primaires sont depuis longtemps utilisés comme indicateurs biologiques de la qualité des milieux aquatiques. La Directive Cadre Européenne sur l’Eau (2000/60/CE) préconise ainsi l’utilisation du phytoplancton, du phytobenthos et des macrophytes afin de mesurer l’état écologique des écosystèmes lacustres. Dans cette étude, ces trois compartiments ont été utilisés pour déterminer l’état écologique de cinq lacs localisés dans la région Aquitaine (Sud-Ouest de la France), lacs ayant la particularité de présenter des niveaux trophiques différents. Les résultats ont montré qu’au niveau intra-lac la composition floristique dépend fortement des variables physiques dans la plupart des systèmes tandis qu’au niveau inter-lac celle-ci dépend du niveau trophique. Le phytoplancton s’est révélé être l’indicateur de qualité le plus performant et le seul utilisable dans les eaux ouvertes, et le plus précis dans les systèmes où les macrophytes submergés étaient absents. Cependant, dans les lacs humiques, les assemblages phytoplanctoniques semblent répondre davantage à la turbidité et aux brassages fréquents de la colonne d’eau qu’aux nutriments. Dans de telles conditions, afin de mieux caractériser la qualité de l’eau, l’utilisation complémentaire du phytobenthos et des macrophytes se révèle plus pertinente. En conclusion, considérant les trois compartiments biologiques, la présente étude permet une approche complémentaire de l’état écologique des systèmes lacustres. Certaines des méthodes appliquées ici représentent un outil potentiel de détermination de la qualité de l’eau selon les exigences de la DCE, mais elles nécessitent d’être affinées pour une meilleure évaluation de l’état écologique des lacs français. Une attention particulière a été portée aux taxa exotiques observés dans ces lacs tempérés, et cet aspect doit être pris en considération lors de l’évaluation écologique. En effet, ces espèces sensiblement avantagées par les conséquences du changement climatique, peuvent altérer la structure et le fonctionnement des écosystèmes aquatiques en place, et aboutir à une perte de diversité. / Due to their important ability to respond to environmental changes, primary producers have been used for a long time as biological indicators of water quality. The Water Framework Directive (2000/60/EC) recommends the use of the phytoplankton, phytobenthos (diatoms) and macrophytes in the ecological status assessment of lakes. In this study, these three compartments have been used to determine the ecological status of five lakes located in the Aquitaine region (southwest of France) with different trophic status. The results showed that within lakes, the floristic composition in most of the systems strongly depends on physical parameters whereas among lakes it depends on the trophic status. The phytoplankton proved to be the most powerful indicator of quality in open-water areas as well as in systems where submerged macrophytes are absent. However, in the humic lakes, the phytoplankton assemblages seem to respond more to turbidity and mixing than to nutrient load. Under such conditions, water quality could be underestimated and the complementary use of phytobenthos and macrophytes appears more appropriated. In conclusion, considering the three biological elements, the present study allows a complementary approach of the ecological status of the lakes. Some of the methods applied here represent a potential tool for the assessment of the ecological status in the context of WFD, but they need to be refined to assess more properly the ecological status of French lakes. A special attention was paid to exotic taxa observed in these temperate lakes, and this aspect must be taken into account in the ecological assessment. Indeed, these species favoured by the consequences of the climate change, can modify the structure and functioning of the aquatic ecosystems, and lead to a loss of diversity.

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