EM - Escola de Minas

URI permanente desta comunidadehttp://www.hml.repositorio.ufop.br/handle/123456789/6

Notícias

A Escola de Minas de Ouro Preto foi fundada pelo cientista Claude Henri Gorceix e inaugurada em 12 de outubro de 1876.

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Resultados da Pesquisa

Agora exibindo 1 - 2 de 2
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    Nutrient recovery in wastewater treatment plants: comparative assessment of different technological options for the metropolitan region of Buenos Aires.
    (2021) Sánchez, Antonio Santos; Martins, Gesaína
    In the metropolitan region of Buenos Aires, the load of nutrients discharged to urban rivers and shores is producing a severe eutrophication problem in the estuary of La Plata River. That problem could be alleviated by recovering nitrogen (N) and phosphorus (P) through the production of fertilizer products in the existing activated sludge treatment plants. Four nutrient recovery options were considered: struvite precipitation in the centrate line; acidic leaching of the sludge followed by struvite precipitation of the centrate; Ion Exchange in the centrate line; and a combination of struvite precipitation in the centrate line plus an Ion Exchange unit to further polish the secondary effluent. Those options were compared with basis on their economic sustainability and their capacity to reduce the load of N and P discharged to the coastal waters and rivers. The economic assessment indicated that producing fertilizer products in the existing facilities, using the four considered options, would be unprofitable. In the best case, which is struvite precipitation in the centrate line, the potential revenues would only cover 38.5 % of the operational expenses. Environmental benefits could justify that cost, as in some urban rivers the load of P could be reduced by 42.5 % by struvite precipitation. Regarding the load of nutrients that is discharged to the estuary, the impact of the considered nutrient recovery options ranges from a decrease in 0.5 % N and 3.7 % P (struvite precipitation) to a decrease in 8.2 % N and 4.4 % P (combination of struvite precipitation + Ion Exchange).
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    Producing electrical energy in microbial fuel cells based on sulphate reduction : a review.
    (2020) Rodrigues, Isabel Cristina Braga; Leão, Versiane Albis
    Combination of the treatment of effluents with high organic loads and the production of electricity is the driving forces stimulating the development of microbial fuel cells (MFC). The increase in electricity production in MFCs requires not only the optimization of the operational parameters but also the inhibition of the metabolic pathways, which compete with electricity production, such as methanogenesis. The presence of both sulphate and sulphide ions in conventional anaerobic reactors hampers the growth of methanogenic archaea and justifies the use of sulphate and therefore sulphate-reducing bacteria (SRB) in the anodic half-cell of MFC. Most importantly, the literature on the subject reveals that SRB are able to directly transfer electrons to solid electrodes, enabling the production of electrical energy. This technology is versatile because it associates the removal of both sulphate and the chemical oxygen demand (COD) with the production of electricity. Therefore, the current work revises the main aspects related to the inoculation of MFC with SRB focusing on (i) the microbial interactions in the anodic chamber, (ii) the electron transfer pathways to the solid anode, and also (iii) the sulphate and COD removal yields along with the electricity production efficiencies.