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The emissions from transport and residential sectors have significant shares in total emissions of Europe. In this study, we identified key priorities in support to the EU Macro-regional Strategies implementation based on an ex-ante assessment focusing on two EU macro-regions: Adriatic-Ionian (AIR) and Alpine (ALP). Firstly, we analysed how different sectors contribute to air pollution in the ALP and AIR regions and to predict future pollution levels under different emission scenarios such as Current Legislation (CLE), Maximum Technically Feasible Reduction (MTFR), and Climate Mitigation (CLIM) by using the TM5-FASST air quality and impact model. It was found that the residential sector is the main contributor to anthropogenic PM2.5 emissions and it will remain so also beyond 2050 under the CLE scenario while the transport sector remains the major contributor to NOx emissions until 2030, with a significant and growing contribution from shipping in the AIR region. Primary PM2.5 has almost reached its technical reduction limit but secondary PM2.5 still has a large reduction potential. MTFR measures on road transport and shipping emissions can generate an annual health benefit from PM2.5 and ozone of 750 (ALP) + 2950 (AIR) avoided premature mortalities in 2050 of which 64% from shipping emission reductions. The potential health benefits from all sectors under MTFR (ALP + AIR) amounts to 16, 800 avoided premature deaths annually in 2030 (3250 + 13550). The potential health benefits from Climate mitigation (ALP + AIR) amounts to 2200 avoided premature deaths annually in 2050 (620 + 1580), however CLIM policies due to fuel switch to biomass also cause air quality trade-off in the domestic sector leading to an estimated number of 360 extra premature deaths annually in 2050 in AIR. Secondly, the experts in the transport sector from these regions have pointed several areas of improvement. Increased intermodality, combining road, rail and maritime ship transport can have important benefits in both regions. In the ALP, moving from trucks to rail could considerably reduce the environmental impacts of transport by reducing emissions of CO2 and air pollutants and could help to solve traffic congestion problems. In the AIR, many countries use outdated technologies for on-road freight transport, causing large environmental impacts. A modal shift e.g. to electric rail or maritime shipping can thus give particularly large positive environmental benefits for this region. The potential drawbacks of a modal strengthening the role of railway and ship transport are primarily related to the increased complexity, the costs of the necessary infrastructures and the risk of increased air pollution in some port cities due to ship emissions. For traffic on roads, infrastructure development is a key element to move towards more sustainable transport. Electrification of road transport generates emissions reductions when the electricity generation is also clean and attention should be given to the charging infrastructure development. Fleet renewal of trucks and ships and use of cleaner fuels will contribute to clean growth in transport. However, fleet renewal is a costly measure and difficult to implement in poor countries ; consequently, the measures that proved to be effective in other countries may not be beneficial or even applicable in these countries. One important obstacle in implementing the provisions of EU macro-regional strategies is the disparity between countries within the macro-regions. Further, some countries in ALP and AIR are not part of EU and may present limitations in international trade and security agreements. Finally, the experts in the field highlighted the fact that bioenergy is an important opportunity for ALP and AIR regions. Because of potential environmental threats, its clean deployment is an issue to be carefully addressed through appropriate policies and regulatory acts. An example is the impact on regional air pollution of small and medium scale traditional appliances and domestic boilers. Improved efficiency and best available technologies need to be strongly supported with both market strategies and effective controls. On the other side of the supply chain, sustainable collection of feedstock has to be assured through the appropriate management of the forest stocks and accounting for the actual climate mitigation benefits, without forgetting the increasing demand of biomass from other industrial sectors in a bio-economy framework.

According to the EU Renewable Energy Directive (2009/28/EC), no direct impacts from residue removal and no GHG emissions should be attributed to cereal residues (straws) when they are removed from agricultural land for the purpose of bioenergy utilization. Crop residues, on the other side, play a critical role in sustaining soil organic matter and preserving soil fertility. How to optimize the trade­off between natural resource preservation and energy resource generation? The application of an “expanded” LCA analysis was assumed and a comparison of three different cropping systems based on wheat cultivation was performed. A crop simulation model (CropSyst) and a Geographical Information System (GIS) were coupled to LCA in order to obtain explicitly spatial distributed results at regional scale. Homogeneous agricultural zones were mapped, thus indicating the area where the best/worst performances were obtained. Our analysis showed that cropping management is a key factor in greenhouse gas emission savings. Sustainable cropping management practices (no­tillage plus cover crops) significantly reduce the total energy demand of the system and save GHG emissions. Therefore, energy from cereal residues can be optimally coupled with grain productions, without detrimental effects on environment, on condition that improved and specifically tailored cropping systems are designed., Proceedings of the 22nd European Biomass Conference and Exhibition, 23-26 June 2014, Hamburg, Germany, pp. 1431-1440

The anaerobic digestion of manure to biogas and its combustion in a Combined Heat and Power engine (CHP) is an option to mitigate GHG emission because, besides reducing the direct emissions of methane and nitrous oxide from manure during its storage, it reduces also carbon dioxide emissions by substituting the fossil fuel needed to produce electricity. We used actual data to analyse a typical dairy farm in Northern Italy. Without biogas plant, the GHG emissions result to be equal to 1.11 kg CO2 eq.kg-1 yr-1 FPCM without allocation of the environmental burden to the by-product meat. With mass allocation, the GHG emissions associated to the milk are reduced to 1.08 kg CO2 eq. kg-1 yr-1 FPCM. Using an economic allocation approach the GHG emissions allocated to the milk are 1.02 kg CO2 eq. kg-1 yr-1 FPCM. The analysis performed shows that the deployment of manure digestion in biogas plants reduces GHG emissions by 31.6 % if the digestate is stored in an open tank. If the digestate storage tank is gas tight and the additional biogas from the storage tank is captured and used in the CHP, the GHG emissions associated to milk production are reduced by 47.3 %., Proceedings of the 21st European Biomass Conference and Exhibition, 3-7 June 2013, Copenhagen, Denmark, pp. 1275-1281

Biogas production is starting to be regarded as a very sustainable practice that can guarantee high GHG savings when upgraded to biomethane. However, sustainability is strongly influenced by many factors, such as the choice of feedstock and operational practices. This paper analyses the impact of several criticalities on the GHG emissions of biomethane production. The system analysed includes the production of biogas and the upgrading to biomethane, which is burnt in a domestic boiler to produce heat. The first critical point is the choice of feedstock. Two substrates are analysed individually: maize and manure. In the case of manure, the residues of digestion and the avoided emissions from manure storage and field application are taken into account. This results in high GHG savings compared to the reference system of producing heat with a natural gas boiler. When maize is used as a substrate, all emissions from cultivation have to be accounted for. A second criticality analysed is the technique used for the upgrading. Four widely used upgrading techniques are considered and the environmental impact analysis shows that the savings depend strongly on which is used. In general the use of biomethane for heat can lead to substantial reduction of GHG emissions. The biomethane pathways, though, have worse environmental performances in eutrophication and in the case of particulate matter the manure pathways have savings while the maize pathways have higher potential than the reference system., Proceedings of the 21st European Biomass Conference and Exhibition, 3-7 June 2013, Copenhagen, Denmark, pp. 1894-1899

This study presents a life cycle analysis of the production of electricity using straw bales and straw pellets. Straw is the most abundant residue in Europe and its use for energy purposes is promoted at every level. However, while studies on the sustainability of the production of liquid biofuels from straw, no literature exists regarding the use of this material for the production of power and heat. Moreover, while straw is nowadays mostly used in bales and traded locally, the production of agri-pellets could create great opportunities to promote and develop international trade markets for biomass fuels. This study uses data from specific literature and emissions inventories in order to model the considered straw pathways. The plant modeled is a medium-scale straw-fired power plant of 50 MWth input capacity. The straw is supplied by trucks from a range of 70 km distance (for the base case). The results indicate that electricity from straw-fired power plants can guarantee high GHG savings in the range of 65 – 80%. The highest emissions are recorded for the case of straw from Spain due to the very small yields, while cultivation processes in UK and The Netherlands show high emissions due to the large level of fertilization used. Other environmental impacts are analyzed, such as acidification potential, eutrophication, respiratory effects and terrestricecotoxicity. The bioenergy system scores largely worse than the reference system for all these categories. Important to notice the impact that heavy metal emissions from biomass combustion could have on terrestricecotoxicity. Finally, the study investigated the "break-eve" distance at which the higher emissions due to the pellets production are paid off by the saved emissions in road transport. The results show that with the assumptions made, actually no reasonable break-even distance exist and even up to 800 km of feedstock transport it would still be better to use straw bales., Proceedings of the 20th European Biomass Conference and Exhibition, 18-22 June 2012, Milan, Italy, pp. 2080-2091

Chemical composition data are being collected for different biomass varieties to investigate the variation in composition. This variation could be important when formulating new standards for biomass quality and certification e.g. for new applications as feedstock in bio­refineries. It is also investigated how this variation can be used in certification of origin and sustainable production of the biomass. The work includes a critical review of literature data combined with experimental studies to determine the chemical composition of biomass varieties and their ashes. Finally, X­ray fluorescence (XRF) spectroscopy on pressed biomass pellets is investigated as a fast analysis technique to quantify enrionmentally problematic and ash­forming elements in a production facility or in the biomass trade market. Some preliminary results are reported here., Proceedings of the 19th European Biomass Conference and Exhibition, 6-10 June 2011, Berlin, Germany, pp. 1958-1961

This dissertation deals with the characterization of several biomass materials under thermal conversion conditions using small--scale equipment. The fuels are tested under the conditions of slow and fast heating rate pyrolysis and combustion, with the main goal of investigating the chemistry of fuel--bound nitrogen. New energy policies put forward in almost every country in the world, and especially in the European Union, are strongly promoting the use of renewable energy sources. Decreasing the use of imported fossil fuels in favour of locally available renewables is the answer to many energy--related problems of the 21st century: global warming, security of supply and high energy prices among some. Among renewable sources, biomass materials hold a special position because they can, in the short term, substitute or integrate fossil fuels in all of their applications applying comparatively few changes to the existing equipment. Biomass wastes, from agriculture or other processes, are convenient in more respects since their use would not only substitute fossil fuels but it would also valorize waste streams. These materials, however, present several issues that are highly delaying their deployment on a large scale. Three of the most important problems are dealt with in this thesis: the heterogeneous nature of the materials, high amount of ash forming matter containing troublesome compounds such as K, Cl and P, and finally, high content of nitrogen. First of all, many biomass residues contain a higher amount of nitrogen compared with woody biomass or even coal. This high content of fuel--N could directly translate into high NOx emissions in combustion conditions or into a high content of nitrogen containing gases such as NH3 and HCN in the syngas from gasification. Primary measures, such as air staging, can be applied directly in the reactor in order to promote the reduction of NOx and NOx--precursors to molecular nitrogen. However, in order to apply such measures and optimize the syngas composition or minimize emissions without relying on expensive catalysts, a detailed knowledge of the mechanisms of fuel--N conversion is required. This thesis has as its main purpose to study the release of volatile nitrogen compounds under pyrolysis conditions and the analysis of the emissions of NO under combustion conditions from high--N fuels. Secondly, as explained in the first two chapters of this dissertation, the definition of biomass is very broad and it includes materials with extremely different composition and characteristics. Additionally, the interest in exploiting some of these materials, such as manures, for energy conversion has never been high enough to trigger substantial research. As a consequence, fundamental data such as reactivity and products distribution are almost completely lacking for many biowastes. One of the purposes of this thesis is, therefore, to gather extensive fundamental data for potential fuels, which have not yet fully characterized. Finally, some elements such as K, Cl, P and S, contained in biomass materials, are known to cause several problems during boiler operation. At high temperatures alkali silicates with melting temperatures lower than the operating one are formed; these partly molten particles can then create issues like slagging, fouling, loss of fluidization and, when Cl is present, corrosion of the boiler surfaces. Together with specific research on boiler materials and optimization of operating conditions, possible pre--treatments used to remove these compounds from the fuel before entering the reactor could greatly enhance the overall process. In this thesis, the effects of a water--leaching pre--treatment on the fuels' reactivity and product yields during pyrolysis are explored. After a general introduction, Chapter 2 has the purpose of providing the reader with an overview of definitions and concepts that are used in the rest of the dissertation. The main components of biomass are listed as well as their behavior under thermal conversion conditions. A special focus is given to nitrogen structures, such as proteins and heterocyclic compounds, and the mechanisms of their decomposition under pyrolysis conditions as reported in available literature studies. Finally, an overview of NOx formation mechanisms is given. The materials studied in this work and the setups used are introduced in Chapter 3. The materials are divided into two main categories: agricultural residues, including wheat straw, olive residues and peach stones, and biomass waste streams, including dry distiller's grains, palm kernel cake and chicken manure. All these materials have a high nitrogen content and are not yet fully exploited because of the issues mentioned above. Several different small--scale setups have been used in this work depending on the conditions that needed to be study. Chapter 4, then, presents the results of measurements performed on agricultural residues under slow pyrolysis conditions. The measurements were carried out using a thermogravimetric analyzer (TGA) connected with a Fourier Transform InfraRed spectrometer (FTIR). All the fuels presented peaks of reactivity at approximately 330 - 360°C associated with the decomposition of cellulose. A shoulder was also found at lower temperatures, approximately 290 - 310°C, and was associated with the pyrolysis of hemicellulose. The main volatile species released resulted to be CO2 for all the fuels followed by CO and methane. No nitrogen compounds were detected because of too little concentrations in the pyrolysis gases which could not be accurately detected by the FTIR. The kinetic parameters for the pyrolysis reactions were found using a Distributed Activation Energy Model (DAEM). This analysis revealed a common reaction path for the main structures (cellulose and hemicellulose) among the various fuels. The water--leaching pre--treatment seemed very effective in removing the troublesome inorganic elements from these fuels. The removed elements, furthermore, had a catalytic effect on the pyrolysis of the fuels; once removed, the samples reacted at higher temperatures and with less reaction paths. Only the peach stones sample, which already had a very low ash content, did not seem to be affected by the treatment. Chapter 5 reports the results of a similar analysis to the previous one, that was performed on different biomass residues: dry distiller's grains with solubles (DDGS) and chicken manure. Also these fuels were found to react with two main peaks at about 280°C and 330°C. Accordingly, also the kinetic parameters resulted very similar to the ones of the agricultural residues, clearly indicating a similar decomposition path for common structures. For DDGS and chicken manure, an additional component was found to react at approximately 400 - 430°C and it was assigned to proteinic structures decomposing. The main volatile nitrogen compounds were found to be NH3 and HCN for DDGS with traces of HNCO. The manure released more of its fuel--bound nitrogen in volatile form and the main compound was found to be HNCO, followed by HCN and ammonia. The water leaching pre--treatment, similarly to what was found for the peach stones sample, did not seem to affect substantially the reactivity of the fuels nor their ash composition. The share of fuel--N released as light volatiles, however, increased for the washed fuels. Building up on the results of the previous two chapters, Chapter 6 describes the results of fast pyrolysis measurements of DDGS and palm kernel cake. These tests were carried out on a heated foil reactor integrated with an FTIR using much higher heating rates, closer to industrial applications. A numerical model of the reactor has been developed in order to have a better insight into the temperature and velocity profiles in the reactor chamber. The simulations, in combination with non--contact temperature measurements, have indicated a significant difference between the expected foil temperature and the actual one. This has been corrected in the experimental campaign, granting a more precise knowledge of the actual conditions. The fast pyrolysis measurements have shown an increased weight loss compared to slow heating rates. CO2 resulted to be still the main light volatile at temperatures below 900°C while CO became more relevant at high temperatures due to tar cracking in the hot area around the foil. Compared to low heating rates measurements of the DDGS sample, HCN was the main volatile nitrogen compound while the yield of NH3 was much lower. The palm kernel cake sample only released detectable yields of HCN, nor ammonia nor HNCO were found. Even at high temperatures, approximately 10% of the initial N was retained in the char of DDGS. The water leaching pre--treatment again did not affect the weight loss behaviour neither the main gaseous product distribution but the yields of light volatile nitrogen compounds increased for the washed samples. After the pyrolysis behaviour of different nitrogen compounds has been analyzed, Chapter 7 presents the results of measurements under combustion conditions for several biomass residues. It is shown that the devolatilization profiles for carbon to CO + CO2 and fuel--N to NO are very similar among very different fuels, implying that a common approach could be taken for their modeling and it could very well be acceptable as a first approximation. Moreover, the conversion of fuel--N to NO appeared to follow a decaying trend where the fuels with lower initial N content presented a higher conversion than fuels with higher nitrogen content. Fuels with high nitrogen content, in fact, are likely to release a larger amount of it in volatile form with a consequent larger amount of NHi radicals available for thermal De--NOx reactions. Finally, the release of carbon as CO2 and nitrogen as NO during devolatilization was found to be proportional for temperatures around 800°C while at 1000°C almost all of the NO was released during devolatilization. Finally, in Chapter 8 the main conclusions of the work described in thesis are drawn and recommendations for future research are expressed.

Increasing needs for lowering carbon emissions and diversifying energy supply make biomass residues an important resource for the production of power and heat. In this paper two residues of liquid biofuels production were tested: dry distiller’s grains & solubles (DDGS) and palm kernel cake (PKC). Both these materials present high nitrogen and inorganic content, which could cause issues such as high NOx emissions, slagging and fouling. The fuels were tested in a heated grid reactor in fast pyrolysis conditions: the setup allowed the study of the fuels under different heating rates (600-1000°C/s) and final temperatures (500°C ÷ 1300°C). Weight loss and yields of main N volatile compounds were measured. The speed of the phenomena involved does not allow for detailed measurement of process conditions in the reactor, therefore, a numerical model was implemented and validated against a non­contact temperature measurement. The model allowed detection of possible zones of high temperature in the reactor volume, the presence of gradients on the grid surface and in the biomass pill. Finally, additional temperature measurements carried out with an infrared pyrometer on the grid indicated a significant difference between the actual temperature and the thermocouple reading., Proceedings of the 18th European Biomass Conference and Exhibition, 3-7 May 2010, Lyon, France, pp. 931-939

We evaluated phagocytic and lytic activities of peripheral blood monocytes (PBMo) from patients with thalassemia major (ThP) using C pseudotropicalis as the target. PBMo from ThP showed decreased lytic activity (P less than .001), whereas the phagocytic activity did not differ from that of the controls. Significant inverse correlations were found between lytic activity of PBMo and age of patients (r2 = .47; P less than .01) and also between lytic activity and serum ferritin levels (r2 = .65; P less than .001). No association was found between lytic activity and other variables (blood transfusion regimens, therapy with desferrioxamine, liver damage, and the presence of sHBAg). Splenectomy showed no positive effect on PBMo functions from ThP. Our results suggest that PBMo from ThP have an intracellular defect in their microbicidal mechanisms associated with iron overload. This cell dysfunction could be responsible, at least in part, for the increased susceptibility to infections reported in ThP.

Purpose: We hypothesize that the current heated scientific debate on bioenergy sustainability is fuelled by flaws in the interpretation phase of bioenergy LCA studies rather than by the lack of studies or shared methodologies. The interpretation phase is the key step in LCA studies, which guarantees their quality and consistency and gives meaning to the work carried out by delivering results that are consistent with the defined goal and scope, which reach conclusions, and explain limitations. Methods: To test our hypothesis, we selected the 100 most cited articles found in Scopus utilizing a query to include most of the relevant works on LCA of bioenergy. The rationale underpinning the choice of the most cited articles is that these are presumably the most influential. A further screening identified off-topic articles, reviews, and methodological papers, which were discarded. We have also checked whether the articles analysed referred to the ISO standards. The study is organized as a reasoned and parametrized review in which we assess the methodological approach of the studies, rather than the results obtained. Results and discussion: We find that overlooking some of the fundamental steps in the interpretation phase in bioenergy LCA is a rather common practice. Although most of the studies referred to the ISO standards, the identification of issues, their framing with sensitivity analyses, and the identification and reporting of limitations, which are all needed to comply with ISO14044 standards, are often neglected by practitioners. The most problematic part of the interpretation phase is the consistency check. In most cases, the assessment framework built is not apt at answering the question set in the goal. Limitations are properly identified and reported only in few studies. Conclusions: We conclude that in many studies either the conclusions and recommendations drawn are not robust because the inventory and the impact assessment phases are not consistent with the goal of the study, or the conclusions and recommendations go well beyond what the limitations of the study would allow. In our opinion, these flaws in the interpretation phase of influential LCA studies are among the responsible factors that continue to fuel the debate around the sustainability of bioenergy. We report a set of recommendations both for LCA practitioners and for users to guide the LCA practitioners in properly organizing and reporting their work, and to facilitate the readers in understanding and evaluating the significance and applicability of the results presented.

The Government of Canada aims at reducing overall greenhouse gas emissions by 30% by 2030 (compared to 2005) and reaching net-zero GHG emissions by 2050. Several of the climate actions under development would incentivize an increased use of forest biomass for energy. However, lessons learned from bioenergy policies worldwide have shown that increasing the use of bioenergy can impact the forest sector as a whole and that the carbon impacts of bioenergy should be assessed holistically to limit unintended negative consequences. This study aims to summarize and present existing data in a manner that enables the Canadian government and stakeholders to identify bioenergy pathways that can contribute to Canada's decarbonization targets. Firstly, we synthetize existing statistical datasets on wood removals and uses into a holistic picture of wood flows across Canada's economy. We find that, in 2017, a minimum of 77.7 Mm3 of wood were used for energy in Canada, and that reported quantities of wood used exceeded the amount of wood removals by 14–33 Mm3 annually. Thus, while 72% of wood used for energy in 2017 derived from secondary industry residues, the origin of 26% of wood for energy cannot be identified, seriously hindering any consideration on the sustainability of the current forest bioenergy use in Canada. Secondly, we assess that the amount of wood used for energy might increase by 5.5–20.4 Mm3 by 2030. In order to identify the potential impacts of this extra bioenergy demand on GHG emissions, we reviewed relevant literature based on our qualitative analysis of the system dynamics of the forest sector in response to such an increased demand. Our results show that unless targeted measures are defined to stimulate the use of residues, it is possible that direct and indirect biogenic GHG emissions from increased use of forest bioenergy will undermine Canada's decarbonization goals. We recommend several measures to avoid this, including: discouraging the dedicated harvest of logs for bioenergy, prioritizing the collection and use of logging residues which are usually burned at roadside, and favoring the recovery and use of post-consumer wood. In addition, we recommend improving the consistency among statistical datasets on Canada's forestry sector.

The demand for wood-based energy is foreseen to grow as energy and climate policies around the world promote the use of bioenergy for climate change mitigation. However, the carbon impacts of forest bioenergy range widely in the literature. The value-choices made on the response of forest management to bioenergy demand have a major influence on the results obtained from modeling exercises and may actually change the contribution of forest bioenergy from climate worsening to climate change mitigation. Despite their relevance, there is very little information, or transparency, as to the empirical basis by which these assumptions are chosen and evaluated against. This study aims to fill in this crucial knowledge gap through a mix of critical review, analysis of historical statistical data, and expert judgement. Several prominent studies reporting climate change mitigation from forest bioenergy in three countries are reviewed: Canada, Sweden, and Southeast USA. This analysis shows that the studies rely on assumptions that bioenergy demand will spur supply responses aimed at more efficient forest management and/or relative increases in forest area. Confronting literature assumptions with trends in historical data, we present the most extensive reality-check of bioenergy literature assumptions to date. We find that studies projecting a large role of forest bioenergy in climate change mitigation rely on assumptions that are too optimistic, at times outright unrealistic. We believe scientists could avoid the misinterpretation of their results and improve the policy relevance of their work by more transparent reporting of: i) value-laden assumptions, ii) their influence on the results, iii) the process and rationale behind such assumptions, especially distinguishing between assumptions that reflect incremental changes in management from assumptions requiring transformational change in several industrial sectors.