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Fluorine is of increasing concern in waste combustion since materials containing fluorinated compounds constitute an increasing share of waste fractions entering combined heat and power plants (CHP). Alkali fluorides could potentially cause similar problems as are well known for the corresponding chlorides. However, there are some fundamental differences in thermodynamic stabilities. Available literature essentially lacks the experimental evidence needed to draw any further conclusions on the extent of any fluorine related problems, but recently a municipal solid waste (MSW)-fired CHP-plant reported alarming deposit growth rates, possibly related to a delivery of fluorine containing fuels. The objective of the present study was to experimentally evaluate some of the thermodynamic considerations mentioned. Fuels were prepared by adding NaCl, NaF and S to softwood pellets. Deposits and aerosol samples were analysed with SEM-EDS and XRD, and evaluated together with fundamental thermodynamic phase equilibrium considerations to provide new and important information on the ash forming reactions and their implications. The results from the combustion experiments showed that the fluorine found on the deposit probe was in form of NaF and Na3F(SO4) in qualitative agreement with thermodynamic equilibrium calculations., Proceedings of the 27th European Biomass Conference and Exhibition, 27-30 May 2019, Lisbon, Portugal, pp. 152-158

Over 640 million people in Africa are expected to rely on solid-fuels for cooking by 2040. In Western Kenya, cooking inefficiently persists as a major cause of burden disease due to household air pollution. The Long-Range Energy Alternatives Planning (LEAP) system and the Life-Cycle Assessment tool Simapro 8.5 were applied for analyzing biomass strategies for the region. The calculation of the residential energy consumption and emissions was based on scientific reviews and original data from experimental studies. The research shows the effect of four biomass strategies on the reduction of wood fuel use and short-lived climate pollutant emissions. A Business As Usual scenario (BAU) considered the trends in energy use until 2035. Transition scenarios to Improved Cookstoves (ICS), Pellet-fired Gasifier Stoves (PGS) and Biogas Stoves (BGS) considered the transition to wood-logs, biomass pellets and biogas, respectively. An Integrated (INT) scenario evaluated a mix of the ICS, PGS and BGS. The study shows that, energy use will increase by 8% (BGS), 20% (INT), 26% (PGS), 42% (ICS) and 56% (BAU). The BGS has the lowest impact on global warming, particle formation, terrestrial acidification, fossil resource scarcity, water consumption, as well as on eutrophication followed by the PGS and INT., Proceedings of the 27th European Biomass Conference and Exhibition, 27-30 May 2019, Lisbon, Portugal, pp. 1536-1542

Pellet boilers are widely used for heat production. In most cases only wood pellets with low ash content are suitable for these appliances due to the increased risk of slagging. The ash fusion test (AFT) is the only standardized method currently available for the prediction of slagging but it frequently failed when solid biofuels were investigated. Therefore different laboratory methods for the prediction of slagging were applied in order to identify the most suitable method for reliable prediction of slagging tendencies. Three laboratory test methods were considered in this investigation: a rapid slag test (1), the so-called "CIEMAT method" (2) and the "slag analyser" (3). The suitability of the obtained results was validated by practical combustion tests in up to nine different pellet boilers. As the most promising method the slag analyser was identified. It will be further developed with the aim to be proposing as an additional standard method for determination of slag related problems in fixed bed combustion systems., Proceedings of the 22nd European Biomass Conference and Exhibition, 23-26 June 2014, Hamburg, Germany, pp. 368-372

Godkänd; 2011; 20111022 (esbpet)

Godkänd; 2011; 20111022 (esbpet)

Availability of traditional biomass fuels such as woody sources for the heating market is restricted to economic considerations (e.g. consumption in paper industries) and locations of these raw materials for pellets production. In Spain, non-traditional biomass sources such as Mediterranean energy crops are starting to be seen as potential future biomass fuels. However, due to their complex chemical composition, they might require specific combustion technologies adapted to their combustion behaviour. Focused on this goal, the main objective of this work was the assessment of combustion operation conditions on bottom ashes transformation behaviour and fractionation of two Mediterranean energy crops (Brassica carinata and Populus ssp.). Two different sizes appliances, a small and a medium grate biomass pellet boiler with a nominal heat output of 25 kWth and 250 kWth respectively, were used to perform the combustions experiments of this work. Evaluation of the fuels in the combustion tests included the collection of samples of slag and bottom ashes, as well as measurements of gaseous compounds (O2, CO, NO/NOx,). All the samples were analysed by means of scanning electron microscope (SEM-EDS) for elemental composition and the X-Ray diffraction for crystalline phase composition. The experimental results revealed that the combustion behaviour of these fuels regarding ash-related problems were due to both their high ash content and proportion of major ash-forming elements (Ca-K-Si-S-P-Mg). However, the melting and sintering behaviour of their ashes were also influenced by means of factors like changes in the combustion conditions due to parameters such as bed movement on the grate, bed temperature, concentration of inorganic gaseous species and air distribution., Proceedings of the 18th European Biomass Conference and Exhibition, 3-7 May 2010, Lyon, France, pp. 1316-1320

Pulmonary cells exposed to diesel exhaust (DE) particles in vitro respond in a hierarchical fashion with protective antioxidant responses predominating at low doses and inflammation and injury only occurring at higher concentrations. In the present study, the authors examined whether similar responses occurred in vivo, specifically whether antioxidants were upregulated following a low-dose DE challenge and investigated how these responses related to the development of airway inflammation at different levels of the respiratory tract where particle dose varies markedly. A total of 15 volunteers were exposed to DE (100 microg x m(-3) airborne particulate matter with a diameter of

Godkänd; 2007; 20080101 (ohmmar)

Upprättat; 2007; 20080101 (ohmmar)

Upprättat; 2006; 20080101 (ohmmar)

Godkänd; 2001; Bibliografisk uppgift: Sider: 1-3; 20080107 (ohmmar)