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High energy prices and an established awareness of the anthropogenic origin of global warming are stimulating markets and policymakers to move toward a much higher utilization of biomass fuels for energy conversion. In order to develop efficient processes, though, much research is still needed to characterize the behavior of such alternative fuels. In this paper the pyrolysis of some agro-residues, abundant in Europe, was studied in a TG-FTIR setup. In order to remove from the samples the alkali metals and Cl which are detrimental for process operation, causing slagging, fouling, and loss of fluidization, a water leaching pretreatment was applied to all the samples. The thermogravimetric curve of wheat straw showed a singular peak at 324 °C and a residue of 21.6 wt % ar. The leaching pretreatment increased the temperature of reaction up to 355 °C and the weight loss to 83.3 wt % ar. The olive residue sample also showed an increase in reacting temperature and volatile release. The peach sample, probably due to its different composition, reacted over two very distinct peaks at 287 and 359 °C. The leaching procedure did not affect this sample on the temperatures of reaction, while it slightly increased the amount of volatiles released. A distributed activation energy method (DAEM) was used to retrieve kinetic parameters from the measurements. When using a discrete distribution with a fixed pre-exponential factor of 2.2 × 1013 [s−1], the main reaction path for wheat straw and olive residue appeared to be at 176 kJ/mol, while for the leached samples and for the peach stones sample it appeared at 184 kJ/mol. The leaching pretreatment removed a high percentage of mineral inclusions in the samples, mostly in the forms of KCl and NaCl. This increased the temperature at which the samples decomposed, increased the released volatiles, and slightly increased the reaction rate.

The European Union (EU) relies largely on bioenergy to achieve its climate and energy targets for 2020\ud and beyond. Special focus is placed on utilization of biomass residues, which are considered to cause low\ud environmental impacts.\ud We used the dataset from the latest European Commission document on the sustainability of solid and\ud gaseous biomass (SWD2014 259), complementing those results by: i) designing three pathways for\ud domestic-heat production using forest logging residues, with different combustion technologies; ii)\ud expanding the analysis to include forest carbon stock development with and without bioenergy; iii)\ud using absolute climate metrics to assess the surface temperature response by the end of the century to a\ud bioenergy and a reference fossil system; iv) including multiple climate forcers (well-mixed GHG, near\ud term climate forcers and surface albedo change); iv) quantifying life cycle impacts on acidification,\ud particulate matter emissions and photochemical ozone formation; v) reviewing potential risks for forest\ud ecosystem degradation due to increased removal of residues.\ud Supply-chain GHG savings of the three pathways analysed ranged between 80% and 96% compared to a\ud natural gas system, above the 70% threshold suggested by the EU. However, the climate impact of bioenergy\ud should be assessed by considering also the non-bioenergy uses of the biomass and by including\ud all climate forcers.\ud We calculate the Surface Temperature Response to bioenergy and fossil systems by means of Absolute\ud Global surface Temperature Potential (AGTP) metric. Domestic heating from logging residues is generally\ud beneficial to mitigate the surface temperature increase by 2100 compared to the use of natural gas and\ud other fossil sources. As long as residues with a decay rate in the forest higher than 2.7%*yr1 are\ud considered as feedstock, investing now in the mobilization of residues for heat production can reduce the\ud temperature increase by 2100 compared to all the fossil sources analysed, both in case of bioenergy as a\ud systemic change or in case of bioenergy as a transitory option.\ud Furthermore, several environmental risks are associated with the removal and use of forest logging\ud residues for bioenergy. These issues concern mostly local air pollution, biodiversity loss and, mainly for\ud stumps removal, physical damage to forest soils.\ud Forest logging residues are not free of environmental risks. Actions promoting their use should\ud consider: (i) that climate change mitigation depends mainly on the decay rate of biomass under natural\ud decomposition and time and rate of technology deployment, (ii) whether management guidelines aimed\ud at protecting long-term forest productivity are in place and (iii) whether proper actions for the management\ud of adverse effects on local air pollution are in place