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ISEP – DEQ – Comunicações em eventos científicos

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http://hdl.handle.net/10400.22/270

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Browsing ISEP – DEQ – Comunicações em eventos científicos by Author "Direito, D."

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  • Pyrolysis of leather wastes from the footwear industry –preliminary results
    Publication . Direito, D.; Pilão, Rosa Maria; Crispim, Alfredo; Ribeiro, A.M.
    Most of the leather used by the footwear industry (more than 70%) is produced from skins and hides tanned with chromium sulphate [1]. The production of leather goods, especially shoes, gives rise to wastes that amount to 15 – 20% of the entry leather [2]. As an example, the European footwear industry generates between 1x105 to 2x105 tons per year of leather wastes [1]. In the last few years, various investigations have been carried out in order to find alternatives to the disposal of these residues in landfills. Several processes have been developed to treat the leather residues that include, among others, combustion, pyrolysis, chemical treatment (oxidation and hydrolysis) or direct application of the wastes [2]. Pyrolysis is the thermal degradation of wastes, in the presence of an inert atmosphere, producing a solid phase (biochar), a liquid phase (bio-oil) and a gas phase composed mainly of CO2, CO, CH4 and H2 [3]. Several authors have reported work on the pyrolysis of chromium tanned leather wastes [4, 5, 6]. [...]
    2019Conference object Open access Show more
  • Slow pyrolysis of oil palm mesocarp fibres: Effect of operating temperature
    Publication . Almeida, A. F.; Direito, D.; Pilão, Rosa Maria; Mayer, B.
    This study investigated the effect of temperature on the slow pyrolysis of oil palm mesocarp fibres. The biomass was characterized in terms of proximate and ultimate analysis, and its higher heating value (HHV) was 18.51 MJ/kg. For pyrolysis temperatures from 469 to 783°C, at a heating rate of 20°C/min, bio-char yield varied between 32.7% and 25.8%. Gas and liquid phases were analysed by gas chromatography and Fourier-Transform Infrared Spectrometry (FTIR), respectively. CO2 was the major gas produced for all temperatures (6.9 to 10.0mol/kg of biomass) and H2 concentration increased rapidly as the temperature rose (0.6 to 8.0 mol/kg of biomass). FTIR measurements show that the bio-oils contained alcohols, phenols, alkanes, alkenes, carboxylic acids, aldehydes and aromatic compounds. The HHV of both bio-chars (27.50 to 28.86 MJ/kg) and bio-oils (25.95 to 28.50 MJ/kg) were measured. Thermal decomposition of the fibres was also studied using thermogravimetric analysis.
    2019Conference object Restricted access Show more