Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-04-19T13:12:37Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Tese de Doutorado - João Nunes - Recuperação de Pb de Escória Metalúrgica por Flotação.pdf: 3142676 bytes, checksum: 24077634f2b469c913c04a7ae58a9678 (MD5) / Made available in DSpace on 2016-04-19T13:12:37Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Tese de Doutorado - João Nunes - Recuperação de Pb de Escória Metalúrgica por Flotação.pdf: 3142676 bytes, checksum: 24077634f2b469c913c04a7ae58a9678 (MD5) Previous issue date: 2015-10-07 / As empresas produtoras de baterias chumbo-ácido são obrigadas, por lei, a reciclar as sucatas de baterias usadas. Em Pernambuco, a reciclagem é feita por processo pirometalúrgico que gera um resíduo denominado de escória, tendo como principais elementos o chumbo e o ferro. Assim, o presente trabalho teve como objetivo estudar a possibilidade de reaproveitar o chumbo contido nesta escória, através do método de flotação. Este reaproveitamento trará um ganho ambiental e econômico a empresa, devido a redução do seu passivo e o alto valor agregado do chumbo no mercado internacional, respectivamente. A fim de caracterização minerológica e química da escória, foram realizadas análises por difração de raios X (DRX), fluorescência de raios X (FRX) e microscopia eletrônica de varredura (MEV), o que possibilitou a escolha de uma rota ideal de tratamento deste resíduo. Os testes de flotação foram realizados em uma célula mecânica de bancada, estudando-se a influência do tipo de coletor, concentração do coletor, tempo de condicionamento, pH da polpa, tempo de flotação, tipos de espumantes de flotação (o metil-isobutil-carbinol - MIBIC e eter-poliglicólico - F650) e ação de agentes modificadores (amido, o sulfeto de sódio e o querosene) com diferentes funções, tais como depressores de ferro, ativadores de chumbo e extensor de cadeia carbônica para aumentar a recuperação do chumbo, respectivamente. Os resultados mostraram que é possível uma recuperação de 54,4 % do chumbo da escória com as partículas na faixa granulométrica de 150 – 400 mesh, com o coletor mercaptobenzotiazol, a uma dosagem de 1.000 g/t, pH 9,0 e tempo de flotação de 20 min. As análises de MEV detectaram a presença de chumbo no interior de partículas de ferro, o que limita a possibilidade de melhorar a sua recuperação. Por sua vez, o xantato etílico de sódio foi bastante seletivo, proporcionando um concentrado com apenas 0,4 % do ferro contido na alimentação, com teor de chumbo de 22,9 %. O teor de chumbo apresentou um valor inferior a 40,0 %, meta proposta pela empresa, devido a presença de carbono no concentrado de flotação, o que não foi considerado um problema, pois os testes piloto mostraram que é possível a sua reutilização na metalurgia do chumbo. / Factories of lead-acid batteries are required by law to recycle battery waste. In Pernambuco, the waste is recycled by a pyrometallurgical process, which produces a residue called slag, that has as main elements lead and iron. Therefore, this work had as a target to study the possibility of reusing the lead of the slag of battery scrap, through the flotation method. This waste recycling will give the company an environmental and economic value, due to the reduction of the quantity of slag and due to a greater recuperation of the lead, especially since its price has been increasing in the international market. For the purpose of minerológica and chemical characterization of the slag, it was performed an analysis by X-ray diffraction (XRD), X-ray fluorescence (XRF) and scanning electron microscopy (SEM), which allowed the choice of an ideal treating for this residue. Flotation tests were carried out in a laboratory cell to study the influence of the type of reactants, the reactant concentration, the adaptation time of the reactants, pH of the pulp, the flotation time, sparkling types of flotation (methyl-isobutyl- carbinol - MIBIC and ether polyglycol - F650) and types of modifying agents (starch, sodium sulfide and kerosene) with different functions, such as iron depressants, carbon chain extender to increase the lead recovery respectively. The results showed that it is possible to arrive at a recovery of 54.4% of the lead with the particles in the size range of 150 - 400 mesh, when we use mercaptobenzothiazole as reactants of flotation, at a dosage of 1000 g/ton, pH 9.0 and flotation time of 20 min. The SEM analysis detected the presence of lead inside the iron particles, which limits the possibility of improving and increasing its recovery. In turn, the sodium ethyl xanthate was quite selective, providing a concentrate with only 0.4% of the iron contained, in relation to the initial mass, and with lead concentration of 22.9%. The lead content showed a value less than 40.0%, of the target proposed by the company, due to the presence of carbon in the form of coke on flotation concentrate, which was not considered a problem since pilot tests showed that it is possible to reuse it in the metallurgical process.

Generation of wastes in the form of liquid, solid or gas is inevitable in any industry.Industrial Solid Waste is the waste that is generated from an industrial or manufacturing process and includes the waste generated from non-manufacturing activities as well.Most of these wastes fall under the category of Ashes, Slagsor Sludges. For the present work, three types of secondary lead slag, two types of granulated blast furnace slag (GBS) or iron slag and four types of steel slags were procured and studied.An elaborate study on various characteristics of the slags has been performed. Based on the results, all the possible applications for the individual slags are considered. The performance of the secondary lead slag as an embankment material was analyzed. The slope stability for various conditionswas analyzed using Geo5 and experimentally determined strength parameters. It was found that the material can be used safely for embankment constructions.The CBR values were very good in the range for both GBS and steel slag,thus repeated load triaxial test are done to determine the resilient modulus. k1-k3model was adopted and the regression coefficients were determined. Based on the results the pavement design is done using KENPAVE software. An exercise has been performed to determine the quantity of the conventional material that could be saved, considering the type and size of the pavement. For the aggregate sized steel slag, the tests were done to find the suitability of the material for various applications like, as railway ballast, concrete aggregate, gabion and rip rap stones. And the tests result shows the material to be suitable for these applications and is expected to perform well. Study on morphological parameters reveals that the size and gradation of any material plays an important role in its mechanical behavior, however in the case of slags, this could be tailor made by using appropriate crushers, as per the requirements.