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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Estimativas da contaminação dos sedimentos dragados no porto de Rio Grande para disposição em solo

Burgueño, Luís Eduardo Torma January 2009 (has links)
Dissertação(mestrado) - Universidade Federal do Rio Grande, Programa de Pós-Graduação em Engenharia Oceânica, Escola de Engenharia, 2009. / Submitted by Lilian M. Silva (lilianmadeirasilva@hotmail.com) on 2013-04-20T17:59:41Z No. of bitstreams: 1 Estimativas da contaminação dos sedimentos dragados no porto de Rio Grande para disposição em solo..pdf: 1923559 bytes, checksum: 6f97d179c3f2dee35f932ef048833ef4 (MD5) / Approved for entry into archive by Bruna Vieira(bruninha_vieira@ibest.com.br) on 2013-06-09T00:57:11Z (GMT) No. of bitstreams: 1 Estimativas da contaminação dos sedimentos dragados no porto de Rio Grande para disposição em solo..pdf: 1923559 bytes, checksum: 6f97d179c3f2dee35f932ef048833ef4 (MD5) / Made available in DSpace on 2013-06-09T00:57:11Z (GMT). No. of bitstreams: 1 Estimativas da contaminação dos sedimentos dragados no porto de Rio Grande para disposição em solo..pdf: 1923559 bytes, checksum: 6f97d179c3f2dee35f932ef048833ef4 (MD5) Previous issue date: 2009 / Este trabalho objetivou avaliar os níveis de contaminação dos sedimentos do canal de acesso ao Porto de Rio Grande – RS, com vistas a sua disposição em terra. Foram analisados os seguintes elementos: As, Cr, Cu, Hg, Ni, Pb, Zn, COT, N-Total e P-Total. Os dados utilizados foram obtidos do Programa de Monitoramento elaborado pela FURG, em 2006, para a SUPRG, para o licenciamento de dragagem de manutenção. Em contraste a estes dados foram utilizados, também, àqueles gerados pela MRS, em 2007, para o licenciamento da obra de prolongamento dos molhes e aprofundamento do canal de acesso ao porto (de 40 para 60 pés). Os três níveis em que foram coletadas as amostras (Topo, Meio e Fundo) foram submetidos ao teste t, para diferenças entre médias, comparados dois a dois. Para cada elemento proposto, foram ajustadas as distribuições de probabilidade, Beta, Gama, Normal, Log-Normal e Weibull. A significância do ajuste das distribuições ao conjunto de dados foi verificada por meio do teste de Kolmogorov-Smirnov. A partir das distribuições que melhor ajustaram-se aos dados observados, foi calculado, para cada elemento o valor esperado para o nível de probabilidade de 0,99. Os valores estimados foram comparados àqueles estabelecidos pela legislação em vigor. Não existem diferenças significativas, ao nível d probabilidade α=0,05, entre os três diferentes níveis amostrados, nas duas séries analisadas. As distribuições que melhor modelaram os dados foram a Beta e a Normal. Os teores encontrados (P≤0,99) comparados aos limites estabelecidos na legislação pertinente denotam que os sedimentos dragados nos canais do porto de Rio Grande poderiam ser dispostos em terra sem impactos significativos ao ambiente. / This work estimates the levels of contamination of the sediments in the access channels to port of Rio Grande - RS, with views at land disposition. The following elements were analyzed: As, Cr, Cu, Hg, Ni, Pb, Zn, COT, total N and total P. The used data were obtained of the Monitoring Program developed by FURG, in 2006, for SUPRG, for the licensing of maintenance dredging. It is composed by a group of 12 sediment cores, with samples collected in three levels of depth. Opposing these datas, was also used the information generated by MRS, in 2007, for the licensing of thework jetties prolongation and deepening of the access channel to the port (from 40 ft to 60ft). This series is constituted of a group of 111 sample points of which 31 are cores in three depth levels. The different levels were submitted to the ttest, for differences among the averages, comparedtwo by two. For each proposed element, probability distributions were adjusted, searching the ones that best represented the series of the data. The tested distributions were: Beta, Gama, Normal, Log-normal and Weibull. The significance of the adjustment of the distributions to the dataset was verified through the test of Kolmogorov-Smirnov. Considering the best distributions adjusted to the observed data, calculations were made, for each element the expected value for the level of probability of 0,99. It doesn’t significant differences, at the probability level α=0,05, among the three different depth sampled, in the both series analyzed. The distributions that best modeled the data were the Beta and the Normal.The estimated values were compared to those established by the legislation. The results found demonstrate that these sediments could be disposed in land without significant impacts to the environment.
2

Traitement et valorisation de sédiments de dragage phosphatés en technique routière / Treatment and valorization of treated dredged sediments in civil engineering

Dia, Moussa 28 May 2013 (has links)
Le dragage des sédiments est nécessaire afin de maintenir le transport et les activités maritimes mais les sédiments extraits sont souvent pollués en métaux lourds et en composés organiques. Face à la nécessité du dragage et à la pollution, la société Solvay a mis au point un procédé permettant de traiter les sédiments dragués pour envisager une valorisation : le procédé Novosol®. Ce procédé a pour but de stabiliser les métaux présents dans les sédiments par phosphatation (ajout d’acide phosphorique H3PO4) et de dégrader la matière organique par calcination à 650°C. Un acide phosphorique pur est habituellement utilisé pour l’étape de phosphatation. Cependant, dans la présente étude plusieurs acides phosphoriques de nature et de sources différentes fournis par la société PRAYON ont été utilisés. Les principales caractéristiques de deux sédiments traités avec plusieurs types d’acides phosphoriques sont présentées dans cette thèse. D’un point de vu mécanique les formulations effectuées avec les sédiments traités sont conformes aux normes routières. L’étude environnementale a montré que les quantités de métaux lourds relarguées par les matériaux formulés à partir des sédiments traités sont inférieures aux seuils fixés par la législation en vigueur. Les résultats obtenus avec les différents types d’acides sont similaires. Cela permet d’envisager l’utilisation des sédiments de dragage traité Novosol® en technique routière. / Dredging of sediments is necessary in order to maintain maritime activities and for flood prevention. However increased industrial activities are causing accumulation of pollutants in the sediments. The main contaminants are heavy metals and organic compounds. Because of the cost of storage, treatment and valorization can be economically sound. This study focuses on the technology to treat heavy metals from dredged sediments using phosphoric acid (H3PO4) (the Novosol®process developed by Solvay company) with a goal to stabilize heavy metals by capturing them in a calcium phosphate matrix and to destroy organic matter by calcination at 650°C. Several studies have been conducted in this field. The stabilized materials obtained have been used in civil engineering. However these studies have never assessed the effect of the composition of the phosphoric acid on the treatment. In this thesis dissertations the effect of two types of phosphoric acids with various purities and origins provide by PRAYON company were compared. The investigation focuses on the effect of the phosphoric acids on the environmental behavior of metals and on the geotechnical properties of the dredged sediment. The environmental study has shown that the concentration of heavy metals released by materials made from treated sediments are below the regulation limits . The results obtained with the different types of acids are comparable. This allows to consider the use of treated dredged sediment by process Novosol® as road materials.

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