Repositório Colecção: Livros e Capítulos de LivrosLivros e Capítulos de Livroshttps://hdl.handle.net/1822/11962024-03-28T20:21:04Z2024-03-28T20:21:04ZPotential of exhausted olive pomace for gasificationCastro, CarlosMota, AndréRibeiro, AndréSoares, MargaridaAraujo, JorgeCarvalho, JoanaVilarinho, Cândidahttps://hdl.handle.net/1822/534672021-02-19T16:05:11ZTítulo: Potential of exhausted olive pomace for gasification
Autor: Castro, Carlos; Mota, André; Ribeiro, André; Soares, Margarida; Araujo, Jorge; Carvalho, Joana; Vilarinho, Cândida
Resumo: The exhausted olive pomace was fully characterized for the application as combustible in gasification. Nowadays, this waste is sold as an animal feed or fertilizer, losing its potential as a combustible for energy production. To analyse the potential as a fuel, a full physic-chemical and energetic characterization were performed. With the results was possible to conclude that: the waste was not dangerous, it is a potential combustible, releases 100.65 W g-1 at 496°C and have a full burning at 600°C. Considering all the results, was conducted a theoretical study, varying the amount of oxygen injected, in a range of 0.21 – 0.39 kmol kmol-1 of waste, allowing the selection of the best work point in terms of net energy. From the theoretical analysis, it was possible to obtain the syngas composition for all the points of the study. The results and directives for the gasification are presented in this paper
<b>Tipo</b>: conferencePaperEffect of temperature in RDF pyrolysisRibeiro, AndréCarvalho, Joana Maria FreitasVilarinho, Cândidahttps://hdl.handle.net/1822/534592021-02-16T19:31:13ZTítulo: Effect of temperature in RDF pyrolysis
Autor: Ribeiro, André; Carvalho, Joana Maria Freitas; Vilarinho, Cândida
Resumo: Refuse Derived Fuel (RDF) is a solid fuel made after basic processing steps or techniques that increase the calorific value of municipal solid waste (MSW). Therefore, energy production from RDF can provide economic and environmental benefits, as reduces the amount of wastes sent to landfill and allows the energy recovery from a renewable source. In this work, it was studied the effect of temperature in RDF pyrolysis collected in a Portuguese company in gas production, gas composition and mass conversion. The effect of reaction temperature was studied at 450, 600 and 750°C. Results showed that, for the same operational conditions, pyrolysis was more efficient at 750ºC. At this temperature, it was obtained a syngas of 11.2 MJ/m3 and a specific gas production of 0.43 m3syngas/kg RDF. Results also proved that the increasing of temperature in pyrolysis reaction enhanced methane production and decreased carbon dioxide concentration in syngas.
<b>Tipo</b>: conferencePaperSuitability of agroindustrial residues for cellulose-based materials productionAraújo, D. J. C.Vilarinho, CândidaMachado, A. V.https://hdl.handle.net/1822/534572019-02-06T16:22:37ZTítulo: Suitability of agroindustrial residues for cellulose-based materials production
Autor: Araújo, D. J. C.; Vilarinho, Cândida; Machado, A. V.
Resumo: The depletion of fossil resources and negative environmental impact related to conventional polymeric materials life cycle have fostered the search for renewable raw materials suitable for their manufacturing. This work aims to present a methodology for the selection of agroindustrial residues with potential to be used as feedstock in cellulose-based materials production. The suitability of main residues identified was calculated taking into consideration their intrinsic characteristics, namely the cellulose content, cellulose-to-lignin ratio and availability. The selection and generation estimates of residues were based on the reality of Portugal’s agriculture sector. The results indicate a range of residues with potential to be used as raw materials. In addition to residues generated in harvest fields, the processing industries can also be considered a potential source of byproducts suitable for the application concerned
<b>Tipo</b>: conferencePaperIncorporation of metallurgical wastes as inorganic fillers in resinsOliveira, AnaMartins, Carla I.Castro, Fernandohttps://hdl.handle.net/1822/531402019-02-06T16:27:00ZTítulo: Incorporation of metallurgical wastes as inorganic fillers in resins
Autor: Oliveira, Ana; Martins, Carla I.; Castro, Fernando
Resumo: This work aims at incorporating industrial wastes arising from the metallurgical sector, as fillers into polymeric resins. The waste materials that were investigated are: brass foundry sand, ferrous slag, inert steel aggregate for construction, white slag from steelmaking ladle secondary treatment, electric arc furnace dusts and aluminum anodizing wastewaters treatment sludge. Two different types of resins were used: a thermoset phenolic resin normally used for the manufacture of foundry molds and a thermoplastic aqueous dispersion vinyl-based resin generally used for soils stabilization and retaining dust. The selection of the most suitable resin for each residue depends on the characteristics of the resins and the waste particle size: for powder residues, it was used a vinyl-based resin, whereas for larger particle size residues a phe- nolic resin has been employed. The goal was to maximize the use of residues; therefore 5 to 15% of phenolic resin or vinyl-based aqueous water dispersion in different concentrations from 10 to 400ml/l was used in the composite preparation and compared to composites made of undi- luted resin. Test samples were prepared by compression molding of parts at room temperature and characterized by mechanical testing (compression and flexion), water absorption test and water leachate analyses (pH determination, soluble salts, and determination of the content of leached elements). After analysis of the main characteristics of these composites it was found that industrial waste incorporation in polymeric resins is a viable way to give value to these presently discarded materials.
<b>Tipo</b>: conferencePaperStudy, design, development and construction of a linear tribometer for testing human skinSeabra, EuricoSilva, Luís F.Martins, JoséLima, Máriohttps://hdl.handle.net/1822/513152021-03-29T09:22:31Z2018-03-01T11:12:19ZTítulo: Study, design, development and construction of a linear tribometer for testing human skin
Autor: Seabra, Eurico; Silva, Luís F.; Martins, José; Lima, Mário
Resumo: The study of the tribological properties of the skin is a very important research field for medical
investigation, development of dermatological products and the analysis of the interactions between textile
products and the skin. To obtain these properties it is necessary to perform tests using tribological
equipments which can simulate the conditions to obtain reliable values that will allow the measurement of
skin wrinkling. The skin aggressions are usually analyzed using special equipments, known as tribometers,
that enable the performance of the tribological characterization of a pair of materials, in order to obtain
parameters such as friction coefficient and wear; for this purpose, the control of test variables, such as
normal applied load, displacement speed, environmental conditions and other relevant circumstances
which influence the interaction of surfaces in contact is required. The most important objective is the
evaluation of a concept commonly known as touch, difficult to define and measure (which is related to the
quantification of the level of comfort provided by the contact with the skin), with the requirement of
studying soft materials, namely the skin. For that purpose it became necessary to design and manufacture a
tribological equipment capable of responding to the demands of the required tests.
<b>Tipo</b>: conferencePaper2018-03-01T11:12:19Z