Microalgas biorremediadoras: tratamentos biológicos e viabilidade de fermentação na produção de bioetanol

• Autor(a) principal: Pereira, Ádson Bruno Costa
• Data de Publicação: 2019
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UFPB
• Texto Completo: https://repositorio.ufpb.br/jspui/handle/123456789/16568
• topic: Biocombustíveis; Biomassa; Microalgas; Bioetanol; Biofuels; Biomass; Microalgae; Bioethanol; Microalgas - Cultivo; Biomassa microalgal; CNPQ::ENGENHARIAS

Considered as one of the most promising biofuels, bioethanol is an alternative and attractive energy source for the future. The high prices of oil and its derivatives, high energy demand and intense environmental debates have a decisive influence in stimulating research on alternative sources of energy. In addition, there is an intense demand for studies that evaluate the influence of the residues of the composition of the various effluents on the biomass productivity. Biofuels produced from microalgae can be an attractive option due to their rapid growth rate, high biomass content, low utilization of arable land and high rate of carbon dioxide absorption, and a good acceptance in the current scenario. Therefore, the objective was to produce bioethanol from microalgal biomass grown in domestic effluents and to analyze the efficiency in bioremediation during cultivation. It was possible to observe that the D467WC strain showed a more pronounced growth curve in the 25% and 50% dilutions of domestic effluent (ED) in relation to the other species studied, however, the growth shown to be more promising in the 25% dilution of ED. The reduction of effluent parameters is observed when comparing the analyzes done before the cultivation, at a 25% dilution, and after the cultivation, attesting that the microalga reduces the levels of ED nutrients, which would contribute to the treatment before water bodies. Cell counting resulted in a cell density equivalent to 43 x 105 cells mL-1, a larger number of cells in the shortest time in the culture in domestic effluent at 25% dilution when compared to the number obtained in the culture in the medium of synthetic WC culture. The dry weight of the obtained biomass was 0.200 g.L-1 and the total sugar content was 35.04%, which when extracted by the acid hydrolysis method yielded 55.6% glucose. From the results obtained in the cultivation and analysis of sugars of the microalgal biomass it is possible to produce bioethanol from the fermentation of the hydrolyzate with the yeast Saccharomyces cerevisiae.