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This paper presents analysis of pine and sunflower husk pellet combustion and their co-combustion with oats in a domestic biomass boiler. Selected physical and chemical properties of the studied biomass pellets were determined. Thermal analysis (TGA) of the analyzed biomass in air atmosphere was carried out. The concentrations of CO, CO 2 , NO and NO 2 in the exhaust gases were also examined. The obtained experiment results were compared with the numerical calculations using CHEMKIN-PRO. The best convergence of the experiment results with the calculations was obtained for a residence time of 2 s and temperature of 650 °C. The experiment and calculated results show that the co-combustion of pellets with oats contributes to reducing the CO and CO 2 concentrations in the flue gas. • Pine and sunflower husk pellets were combusted and co-combusted with oat in a domestic biomass boiler. • Selected physical and chemical properties, of the studied biomass pellets were determined. • Thermal analysis (TGA) of the analyzed biomass in air atmosphere was carried out. • The concentrations of CO, CO 2 , NO and NO 2 were examined and compared with the numerical calculations. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pyrolysis technology can be successfully applied into RDF conversion. • Heating value of pyrolytic gas was estimated at the level about 24 MJ/m3. • Residence time significantly influences the pyrolytic gas composition. • Computer simulations predicted the chemical composition of pyrolytic gas. The current COVID-19 pandemic situation and the associated restrictions have increased the amount of generated waste. It results from the necessity to wear personal protective equipment. Thus, the disposal of masks and gloves is a topical issue and requires immediate investigation. The main aims of this work are management and environmental studies of municipal solid wastes (MSW), which have been generated during the COVID-19 pandemic time. Effective waste management in relation to a circular economy is presented. A sample of refuse derived fuel (RDF) with a high content of plastics was used for the experimental and calculation studies. Pyrolysis was selected as the best thermal decomposition process for this kind of wastes. Proximate and ultimate analyses were performed for RDF and its products. Pyrolysis was carried out using a pilot-scale reactor with a continuous flow of 250 kg/h at 900 °C. Thermogravimetric analysis was applied during the pyrolysis investigation and showed that the main decomposition of RDF took place in the temperature range of 250–500 °C. The pyrolysis gas contained combustible compounds like CO (19.8%), H 2 (13.2%), CH 4 (18.9%) and C 2 H 4 (7.1%), giving a high calorific value – 24.4 MJ/m3. The experimental results were implemented for numerical calculations. Chemkin-Pro software was applied to predict the chemical composition of the pyrolysis gas. The performed computer simulations demonstrated very good agreement with the results obtained during the experiments. They also indicated that there is a strong relationship between the chemical composition of the pyrolysis gas, the process temperature and residence time in the reactor. [ABSTRACT FROM AUTHOR]

The paper evaluates the possibility of efficiently processing waste generated in the process of biomass torrefaction into a non-toxic material, suitable for practical reuse. The water was evaporated from the liquid fraction resulting from the torrefaction of Virginia mallow, after which the resulting sludge was subjected to vitrification. The vitrification process was carried out at 1450 °C using tempered glass cullet, which constituted 85% by weight of the total processed material. The obtained product was subjected to the following analyses: microstructural characterization, X-ray diffraction, energy dispersive spectroscopy, spectroscopic tests, as well as measurements of hardness and ion leachability in an aqueous medium. It was found that vitrification of the sludge obtained from the waste liquid fraction leads to incorporation of the inorganic components of the waste into the glass structure, and in the case of organic components, causes their thermal decomposition. As a result of vitrification, a product was obtained that has no toxic properties and is characterized by favorable utility properties, i.e. low ion leachability and high hardness, higher than the hardness of the glass used in the vitrification process. The conducted research showed that vitrification is an effective method to recycle waste generated in the production process of treated biomass, and the product of the vitrification process can be used, for example, in the production of glassy building materials. • Wastes generated during biomass torrefaction can be effectively vitrified. • Vitrification process converts biomass torrefaction waste into a harmless product. • Vitrificat is amorphous and characterised by high hardness and low ion leachability. • Vitrification may be an alternative to other waste disposal techniques. [ABSTRACT FROM AUTHOR]

The possibility of utilizing calumite (BSF) in the glass-ceramic industry was analyzed in this study. The properties of melaphyre glasses modified with 25 % and 50 % of calumite were determined after the post-melting and directional crystallization process. The produced glasses were subjected to microstructural analysis using light LM and scanning electron microscopy SEM. Their chemical composition was determined using XRF spectroscopy. After melting and directional crystallization, the glasses' structural tests were performed using FTIR spectroscopy and XRD phase analysis. The characteristic temperatures and the thermal stability of the glasses were determined with thermal analysis (DTA/TG) and dilatometric tests, which analysis was also valuable to determine the parameters of the directional crystallization process of melaphyre glasses. The results showed that unmodified melaphyre glasses demonstrate a low crystallization ability and do not crystallize even at 900 °C, while incorporating calumite into their composition increases their crystallization ability. The study showed that calumite significantly influences the chemical and structural characteristics of melaphyre glasses, which gives it the chance to be successfully used as a raw material for producing glass crystalline materials or mineral fibres. Notably, the findings underscore the potential utility of calumite as a proficient raw material for fabricating glass crystalline fibrous or insulating materials. [ABSTRACT FROM AUTHOR]

Sida hermaphrodita is one of the energy crops with high potential for energy conversion technologies. In this study the torrefaction of Sida hermaphrodita was carried out at the specially constructed test bench simulating industrial like process operating conditions. The torrefaction temperature was in the range from 250 to 350 °C. The obtained solid products (biochars) were characterized in terms of its proximate and ultimate properties. The chemical analysis of liquid phase was also performed. The combustion process of obtained biochars was examined by Simultaneous Thermal Analysis (STA) through dynamic runs at 10 °C/min heating rate from RT to 700 °C. The structural changes during the torrefaction were studied using scanning electron microscope technique. The fibre analysis was performed to determine structural composition (the content of hemicellulose, cellulose and lignin). Results from analyses significantly contributed to extending databases in the field of plant torrefaction. The results confirmed positive features of obtained biochars comparing to raw biomass material. It was concluded, that the optimal process temperature for Sida hermaphrodita should not exceed 400 °C. Additionally, the mineral matter was investigated using X-ray Fluorescence (XRF) to study the influence of torrefaction on chemical composition of the ash. Only some differences in ash compounds were observed. • Sida Hermaphrodita torrefaction process were conducted at specified temperatures. • Increasing process temperature leads to enhance energy properties of obtained biochar. • The fibre and structural analyses confirmed the changes in morphology structure. • Condensates of torrefaction contained high amount of organics. [ABSTRACT FROM AUTHOR]

Abstract The main problem and also challenge was to find a satisfactory effective tool for real-time control the torrefaction/pyrolysis process of biomass and to evaluate (also in real-time conditions) biochar quality. This paper presents results from investigation on a new method for both evaluating biochar quality and control biomass thermal processing at temperatures of 300, 350 and 400 ◦ C. Thermal processing of biomass in this temperature range is torrefaction and pyrolysis. Investigation was focused on processing Virginia Mallow (Sida Hermaphrodita) energetic crops. Several strong correlations were observed as follows: carbon and hydrogen content in biochar (charcoal), oxygen content, ash and volatile matter from biochar, calorific value and temperature of the process and finally, acetic acid in condensate and carbon content in the biochar. The results show that the content of acetic acid, being one of the major compounds present in the condensate (black liquor, biooil), is in satisfactory linear correlation with the process temperature and furthermore, with carbon content in biochar. The mathematical description for this polynomial function was proposed as follows: Carbon (%) = 0.6e-3 x Acetic Acid (ppm)+49.5. The correlation between acetic acid in black liquor and carbon in biochar was used to introduce a new method which can be considered as a diagnostic tool for determining biochar quality in real-time conditions during biomass thermal processing. Hence, carbon content in biochar as well as its calorific value can be determined by measuring percentage of acetic acid in the condensate. This correlation was considered as the main novelty presented here. This method provides relatively fast evaluation of quality of biochar produced in industrial scale torrefaction systems, what makes it possible to optimize process parameters (temperature, retention time) in real time conditions and improve biochar production process in this way. Highlights • C H tradeoff for biochar is in strong linear negative correlation. • Acetic acid in biooil increased from 5 to 25% with process temperature increase. • Acetic acid in biooil is verifiable correlated with carbon content in biochar. • Acetic acid vs. carbon correlation can be used to control biochar quality. [ABSTRACT FROM AUTHOR]

The article presents the results of RDF (Refuse Derived Fuel) examination in order to use it for energy purpose. RDF material was subjected to thermogravimetric analysis. The TGA analysis confirmed the multi-component nature of tested material. It also indicated that the mixture consists of a minimum of 2 types of materials: biomass and thermoplastic polymers. The pyrolysis was conducted as a batch process with the use of a processing furnace supplied by the IZO Company. RDF sample was pyrolysed under 900 °C in a nitrogen atmosphere. Obtained char and gaseous sample, as well as raw material, were subjected to elemental and gas chromatographic analysis. Furthermore, using ANSYS CHEMKIN-PRO software, numerical simulations of these samples were conducted. Based on the results of composition of pyrolysis gas, the numerical model was validated. Next, modelling of chemical composition of gas from RDF pyrolysis for a pilot installation working in Poland was performed. In addition, the evaluation of the investment costs for the exemplary installation for the thermal conversion of RDF using pyrolysis was made. For this purpose, dynamic methods of investment project assessment were used, which take into account the distribution of anticipated revenues and expenses related to a given investment project over time. • Refuse Derived Fuel (RDF) can be a valuable energy source. • Thermal conversion of RDF by pyrolysis can contribute to limiting waste landfilling. • Calculations with the use of the ANSYS CHEMKIN-PRO software were conducted. • Economic analysis confirmed the legitimacy of the analysed investment. [ABSTRACT FROM AUTHOR]

There can be observed global interest in waste pyrolysis technology due to low costs and availability of raw materials. At the same time, there is a literature gap in forecasting environmental effects of thermal waste treatment installations. In the article was modelled the chemical composition of pyrolysis gas with main focus on the problem in terms of environmental hazards. Not only RDF fuel was analysed, but also selected waste fractions included in its composition. This approach provided comprehensive knowledge about the chemical composition of gaseous pyrolysis products, which is important from the point of view of the heterogeneity of RDF fuel. The main goal of this article was to focus on the utilitarian aspect of the obtained calculation results. Final results can be the basis for estimating ecological effects, both for existing and newly designed installations. Pyrolysis process was modelled using Ansys Chemkin-Pro software. The investigation of the process were carried out for five different temperatures (700, 750, 800, 850 and 900 °C). As an output the mole fraction of H 2 , H 2 O, CH 4 , C 2 H 2 ,C 2 H 4 , C 3 H 6 , C 3 H 8 , CO, CO 2 , HCl and H 2 S were presented. Additionally the reaction pathways for selected material were presented. Based on obtained results, it was established that the residence time did not influenced on the concentration of products, contrary to temperature. The chemical composition of pyrolytic gas is closely related to wastes origin. The application of Chemkin-Pro allowed the calculation of formation for each products at different temperatures and formulation of hypotheses on the reaction pathways involved during pyrolysis process. Further, based on the obtained results confirmed the possibilities of using pyrolysis gas from RDF as a substitute for natural gas in energy consumption sectors. Optimization of the process can be conducted with low financial outlays and reliable results by using calculation tools. Moreover it can be predicted negative impact of obtained products on the future installation. [ABSTRACT FROM AUTHOR]

This paper concerns the flame extinguishing with the use of acoustic waves. A small laboratory stand allowing to generate acoustic waves in the horizontal direction was used for that purpose. The speaker extinction power and the acoustic extinction pressure were selected to quantify the process. Varying frequencies (30–50 Hz) burner powers (3.45-11.72 kW) and distances between the acoustic source and the flame (0.02–0.06 m) were investigated. It was shown that the lower the frequency is it is easier to extinguish the flame. It was also found that the fuel load has a minor impact on the extinction pressure. The results are supplemented with the visualisation of the flame behaviour under the influence of acoustic waves performed with the use of Schlieren apparatus. It was shown that the extinction is a result of cumulative effect of acoustic mean flow and oscillatory perturbations. [ABSTRACT FROM AUTHOR]

A novel approach, linking both experiments and modelling, was applied to obtain a better understanding of combustion characteristics of torrefied biomass. Therefore, Pine, Acacia and Miscanthus giganteus have been investigated under 260 °C, 1 h residence time and argon atmosphere. A higher heating value and carbon content corresponding to a higher fixed carbon, lower volatile matter, moisture content, and ratio O/C were obtained for all torrefied biomass. TGA analysis was used in order to proceed with the kinetics study and Chemkin calculations. The kinetics analysis demonstrated that the torrefaction process led to a decrease in Ea compared to raw biomass. The average Ea of pine using the KAS method changed from 169.42 to 122.88 kJ/mol. The changes in gaseous products of combustion were calculated by Chemkin, which corresponded with the TGA results. The general conclusion based on these investigations is that torrefaction improves the physical and chemical properties of biomass. [ABSTRACT FROM AUTHOR]

The study assessed the possibility of using waste glass cullet from the screen part of CRTs (cathode ray tube) in the vitrification of asbestos-cement materials (ACM). The composition consisting of 50% by mass ACM and 50% by mass cullet was subjected to vitrification. The research material before and after vitrification was subjected to comparative analysis. As a result of vitrification, a transparent amorphous material was produced with a hardness about 7% higher than that of CRT glass and lower ion leachability in an aqueous environment compared to ACM. X-ray and spectroscopic examinations did not reveal the presence of chrysotile, i.e. a type of asbestos found in ACM. This fact proves that during vitrification the asbestos decomposed and formed a lattice of glass composed of the products of this decomposition. Moreover, the presence of heavy metals in the vitrified product was found, including Ba and Sr, the source of which was the CRT cullet. The obtained research results prove that ACM vitrification with CRT cullet leads to the effective utilization of both types of waste during one technological process. Therefore, the vitrification of ACM can be successfully carried out using waste CRT glass, and the harmless product obtained in the vitrification process can be used in practice. The use of CRT cullet in the vitrification of asbestos-cement materials will also have a positive impact on the environment as it will reduce the amount of electronic waste deposited in landfills. [Display omitted] • The vitrification of ACM can be successfully carried out using CRT glass cullet. • It is possible to simultaneously dispose of ACM and CRT cullet in one process. • The vitrification process transforms the hazardous wastes into a harmless product. • Vitrification is an effective method of neutralizing asbestos-cement materials. • The vitrification process leads to the complete decomposition of chrysotile. [ABSTRACT FROM AUTHOR]

[Display omitted] • A study of oat straw pyrolysis was performed at various temperatures. • Multifaceted analysis of gas, liquid and solid phases was carried out. • Pyrolytic gas quality increased with temperature. • Chemkin modelling of pyrolysis allowed to predict chemical composition of syngas. Biomass wastes are sustainable, renewable, and promising energy sources. In this study, the pyrolysis of agricultural biomass was investigated to determine the most promising process parameters for pyrolytic gas production. The pyrolysis investigations were carried out under nitrogen atmosphere at 300, 400, 500, and 600 °C on the microscale using simultaneous thermal analysis and a laboratory-scale semi-batch vertical reactor. The solid, liquid, and gaseous products were characterised in detail, including the elemental and chemical composition. The gas and liquid products analyses were provided. It was found that the quality of the pyrolytic gas increased with temperature, both in terms of the pyrolytic gas yield and concentration of gaseous components (hydrogen and methane), whereas the carbon dioxide concentration decreased with temperature. The condensed vapours were rich in phenolic and aromatic compounds, and it was noted that the acetic acid concentration increased with temperature. The chemical functional groups in the char were determined using infrared spectroscopy. The carbon content increased with temperature, whereas the hydrogen content decreased. Further decomposition of the organic matrix was observed with increasing temperature. Additionally, chemical modelling of pyrolytic gas was performed using Ansys Chemkin-Pro software and compared with the experimental results. The computational results showed a good correlation with the measured pyrolytic gas composition, especially in the case of the major gas components. [ABSTRACT FROM AUTHOR]