Novas formulações de fluidos de corte: otimização, propriedades e recuperação do óleo usado
Cutting fluids are lubricants used in metal-mechanical industries. Their complex composition varies according to the type of operation carried out, also depending on the metals under treatment or investigation. Due to the high amount of mineral oil produced in Northeastern Brazil, we have detected...
Sábháilte in:
Príomhchruthaitheoir: | |
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Rannpháirtithe: | |
Formáid: | doctoralThesis |
Teanga: | por |
Foilsithe / Cruthaithe: |
Universidade Federal do Rio Grande do Norte
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Ábhair: | |
Rochtain ar líne: | https://repositorio.ufrn.br/jspui/handle/123456789/17688 |
Clibeanna: |
Cuir clib leis
Níl clibeanna ann, Bí ar an gcéad duine le clib a chur leis an taifead seo!
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Achoimre: | Cutting fluids are lubricants used in metal-mechanical industries. Their complex composition varies according to the type of operation carried out, also depending on the metals under treatment or investigation. Due to the high amount of mineral oil produced in Northeastern Brazil, we have detected the need to better use this class of material. In this work, two novel formulations have been tested, both based on naphthenic mineral oil and additives, such as: an emulsifying agent (A), an anticorrosion agent (B), a biocide (C) and an antifoam agent (D). Each formulation was prepared by mixing the additives in the mineral oil at a 700-rpm stirring velocity for 10 min, at 25°C, employing a 24 factorial planning. The formulations were characterized by means of density, total acid number (TAN), viscosity, flash point and anticorrosion activity. In a subsequent study, oil-in-water
emulsions were prepared from these novel formulations. The emulsions were analyzed in terms of stability, corrosion degree, percentage of foam formation,
conductivity, accelerated stability and particle size. The samples were appropriately labeled, and, in special, two of them were selected for featuring emulsion properties which were closer to those of the standards chosen as
references (commercial cutting oils). Investigations were undertaken on the ability of NaCl and CaCl2 to destabilize the emulsions, at concentrations of 2%, 5% and
10%, at an 800-rpm stirring velocity for 5 min and temperatures of 25º, 40º, 50º and 60ºC. The recovered oils were chemically altered by reincorporating the same
additives used in the original formulations, followed by preparation of emulsions with the same concentrations as those of the initial ones. The purpose was to
assess the possibility of reusing the recovered oil. The effluents generated during the emulsion destabilization step were characterized via turbidity index, contents
of oil and grease, pH, and contents of anions and cations, observing compliance with the parameters established by the current environmental legislation (Brazil s CONAMA 357/05 resolution). It could be concluded that the formulations presented excellent physicochemical properties as compared to commercial cutting fluids, showing that the quality of the newly-prepared fluids is superior to that of the formulations available in the market, enabling technically and environmentally-safe applications |
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