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Abstract: Biomass as an energy source has a lot of advantages over fossil residues, but it presents an important drawback: in local environments, such as homes, people are exposed to some harmful gases evolved during the biomass degradation process. Thus, many efforts have been made in order to dismiss these pollutants, being the blending with less pollutant biomass materials (that is, dilution), the optimization of the energy obtaining process and the use of catalysts and adsorbents the most popular ways to achieve this goal. The aim of this research was to assess the effectiveness of dilution over grape pomace, a quite abundant residue in Extremadura (Spain), blending it with Pyrenean oak. During the combustion of these blends, some parameters were measured by a coupled TG-MS technique, which allowed us to obtain much information about kinetics and evolved gases emissions. It is shown how the dilution effect affects both the amount of evolved gases (reducing them) and the combustion mechanism. [Copyright &y& Elsevier]

Abstract: As a result of agroindustrial activities in southwestern Europe, a great amount of residues are generated; among them, olive pomace stands out as one of the most abundant. One interesting alternative to increase its potential as biofuel can be its densification. However, in order to achieve high quality pellets, it is necessary to blend this material with other feedstocks. In this work, the properties of blends of pelletized residues from olive pomace and pyrenean oak were analyzed with a view to find the best option. In order to compare the characteristics of the obtained pellets, such as moisture content, mechanical durability, ash content and calorific value, these parameters were determined according to the Technical Specifications for Solid Biofuels CEN/TS. Moreover, the pellets produced were subjected to a combustion test in a pellet stove to analyze the emissions associated to each sample. The results show that not all residues pelletize satisfactorily, which is due to the different conditions of the precursors. Adding pyrenean oak residues to the olive pomace samples guarantees a more effective compression of the pellet, improving its manipulation and transport, without significantly modifying its thermal properties. Concerning the pellet combustion, emissions are slightly worse with olive pomace pellet, concluding that it is not recommendable to use blends with more than 50% of this product. [Copyright &y& Elsevier]

Abstract: One possibility for the elimination of the by-products generated in the viticulture industry can be their densification for subsequent use as a solid biofuel. In this work, washed grape pomace has been considered due to its thermal characteristics. Since it could show problems in the densification process, other by-products such as pyrenean oak residues, with good pelleting properties and available in this region, are also used. So that, samples of different concentrations from both residues were densified by means of a flat die pelletizer, obtaining pellets of 6mm diameter. The densified samples were characterized in terms of the proximate and ultimate analyses, heating value and physical characteristics such as durability or bulk density. Also, the combustion profile of the pellets was studied by thermogravimetry and inorganic emissions such as sulphur dioxide and nitric oxide were considered, by means of coupled mass spectrometry (TG-MS). The results obtained showed that both residues show good characteristics for their densification and manufacture in pellets. Also, they show good physical and thermal properties for its use as biofuel, as well as its different blends. Therefore, it is possible to give a more efficient energetic use to both residues. [ABSTRACT FROM AUTHOR]

Abstract: The thermal decomposition of pellets made from pyrenean oak (PK) and olive waste pomace (OP) mixed under different proportions (0–100wt.% of OP) was studied. Mass spectra measurements were accomplished simultaneously in order to elucidate the emissions generated during the weight loss of the lignocellulosic materials. The coupled TG–MS study allowed the monitoring of the emissions of CO2, SO2, NO, C6H6 and C7H8, and the differences found were related to the chemical composition of the precursors and also to the features of their thermal degradation. It was found that in general a high content of OP favors the release of these emissions at lower temperatures. On the other hand, the effect of OP content on the ion intensity height of the emissions is more marked in the range 25–75wt.% of OP. The analysis of the emission profiles for each case allows a proper design of the experimental conditions in order to get a better control of the process. [ABSTRACT FROM AUTHOR]