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Abstrakt

Pellety drzewne są klasyfikowane jako biomasa stała. Stanowią jedno z najpopularniejszych w Europie paliw stosowanych do ekologicznego ogrzewania, szczególnie w sektorze małego ciepłownictwa, spalane są w domowych kotłach małej mocy. Popularność pelletu oraz automatycznych urządzeń grzewczych umożliwiających spalanie tego paliwa wzrosła ze względu na rosnący problem zanieczyszczenia powietrza atmosferycznego (smogu) oraz w związku z licznymi powstającymi programami ograniczenia niskiej emisji (PONE). Pellet drzewny powstaje w wyniku kompresji materiału pochodzącego z drzew iglastych (w główniej mierze) oraz liściastych i zaliczany jest do odnawialnych źródeł energii. Celem prezentowanych badań było porównanie jakości pelletów drzewnych pochodzących od różnych producentów, wykorzystywanych w domowych kotłowniach na paliwa stałe na podstawie jakościowej i ilościowej identyfikacji zanieczyszczeń obecnych w badanym paliwie uzyskanym z rynku krajowego. Innowacją w prezentowanej pracy jest zastosowanie analizy petrograficznej dla paliwa w postaci pelletu, która dotychczas stosowana była jedynie w odniesieniu do paliw kopalnych. Analizę mikroskopową przeprowadzono zarówno dla pelletów certyfikowanych (EN Plus/DIN Plus), jak i niecertyfikowanych dostępnych na rynku. Niestety, analiza wykazała obecność niebezpiecznych kontaminacji w obu typach pelletu. Niedopuszczalne wtrącenia organiczne w analizowanych próbkach to: węgle kopalne i ich pochodne oraz materiały polimerowe pochodzenia naturalnego. Niedozwolone inkluzje nieorganiczne wyznaczone w analizowanych próbkach to: rdza, kawałki metalu, tworzywa sztuczne i materiały polimerowe pochodzenia nieorganicznego.
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Słowa kluczowe SRF co-combustion fly ash CFB

Abstrakt

Due to the fact that the landfill deposition of municipal waste with the higher heating value (HHV) than 6 MJ/kg in Poland is prohibited, the application of waste derived fuels for energy production seems to be good option. There is a new combined-heat-and-power (CHP) plant in Zabrze, where varied solid fuels can be combusted. The formation of ashes originating from the combustion of alternative fuels causes a need to find ways for their practical application and demands the knowledge about their properties. Therefore, the present work is devoted to studying the co-combustion of solid recovered fuel (SRF) and coal, its impact on fly ash quality and the potential application of ashes to synthesis zeolites. The major objectives of this paper is to present the detail characteristics of ash generated during this process by using the advanced instrumental techniques (XRF, XRD, SEM, B ET, TGA). The co-combustion were carried out at 0.1 MWth fluidized bed combustor. The amount of SRF in fuel mixture was 1, 5, 10 and 20%, respectively. The focus is on the comparison the ashes depending on the fuel mixture composition. Generally, the ashes characterise high amounts of SiO2, Al2O3 and Fe2O3. It is well observed, that the chemical composition of ashes from co-combustion of blends reflects the amount of SRF addition. Considering the chemical composition of studied ashes, they can be utilize as a zeolites A. The main conclusions is that SRF can be successfully combusted with coal in CFB technology and the fly ashes obtained from coal + SRF fuel mixtures can be used to synthesis zeolites.
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Abstrakt

The aim of the study was to evaluate the effect of pre-sowing seed stimulation of Thuringian Mallow (Lavatera thuringiaca L.) with He-Ne laser light of different exposure times on the crop yield as well as on energetic parameters such as calorific value and combustion heat. Seeds were subjected to laser light with an exposition time of 0, 1, 5, 10, 15 and 30 minutes. Measurements were carried out independently on mature plants from the first and second vegetation year. The results varied between the samples, which indicated possible impact of laser radiation on the resultant weight and calorific value of various experimental combinations. For plants from the second vegetation year the statistical differences in calorific value, combustion heat and crop mass were found between samples characterized by different exposition times: between sample irradiated for 30 min (L30) and 1 min (L1) as well as between sample L30 and sample irradiated for 5 minutes (L5). For plants after the first vegetation year the statistically significant differences in calorific value and combustion heat were found for sample with exposition time of 15 minutes (L15) and control sample, for sample L15 and sample L5 as well as between samples L15 and L30. For all the samples from the second vegetation year the increase in combustion heat and calorific values were detected as compared to control. Thus, after the application of certain parameters of laser radiation to the processing of seeds, the plant can be more useful for energetic purposes through more efficient crop.
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Abstrakt

The work presents results of solution combustion method utilization for yttria (Y2O3) nanopowder fabrication. Experiments were carried out with four different reducing agents: urea, glycine, citric acid and malonic acid added in stoichiometric ratio. The reactions were investigated using simultaneous DSC/DTA thermal analysis. After synthesis the reaction products were calcined at temperature range of 800-1100°C and analyzed in terms of particle size, specific surface area and morphology. Best results were obtained for nanoyttria powder produced from glycine. After calcination at temperature of 1100°C the powder exhibits in a form of nanometric, globular particles of diameter <100 nm, according to SEM analysis. The dBET for thus obtained powder is 104 nm, however the powder is agglomerated as the particle size measured by dynamic light scattering analysis is 1190 nm (dV50).
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Abstrakt

Y2O3-MgO nanocomposites are one of the most promising materials for hypersonic infrared windows and domes due to their excellent optical transmittance and mechanical properties. In this study, influence of the calcination temperature of Y2O3-MgO nanopowders on the microstructure, IR transmittance, and hardness of Y2O3-MgO nanocomposites was investigated. It was found that the calcination temperature is related to the presence of residual intergranular pores and grain size after spark plasma sintering. The nanopowders calcined at 1000°C exhibits the highest infrared transmittance (82.3% at 5.3 μm) and hardness (9.99 GPa). These findings indicated that initial particle size and distribution of the nanopowders are important factors determining the optical and mechanical performances of Y2O3-MgO nanocomposites.
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