In this study, 12 organic waste materials were subjected to TG/DTG thermogravimetric analysis and DSC calorimetric analysis. These analyses provided basic information about thermochemical transformations and degradation rates during organic waste pyrolysis. Organic waste materials were divided into six basic groups as follows: paper, cardboard, textiles, plastics, hygiene waste, and biodegradable waste. For each group, two waste materials were selected to be studied. Research materials were (i) paper (receipts, cotton wool); (ii) cardboard (cardboard, egg carton); (iii) textiles (cotton, leather); (iv) plastics (polyethylene (PET), polyurethane (PU)); (v) hygiene waste (diapers, leno); and (vi) biodegradable waste (chicken meat, potato peel). Waste materials were chosen to represent the most abundant waste that can be found in the municipal solid waste stream. Based on TG results, kinetic parameters according to the Coats–Redfern method were determined. The pyrolysis activation energy was the highest for cotton, 134.5 kJ × (mol∙K)⁻¹, and the lowest for leather, 25.2 kJ × (mol∙K)⁻¹. The DSC analysis showed that a number of transformations occurred during pyrolysis for each material. For each transformation, the normalized energy required for transformation, or released during transformation, was determined, and then summarized to present the energy balance. The study found that the energy balance was negative for only three waste materials—PET (−220.1 J × g⁻¹), leather (−66.8 J × g⁻¹), and chicken meat (−130.3 J × g⁻¹)—whereas the highest positive balance value was found for potato peelings (367.8 J × g⁻¹). The obtained results may be applied for the modelling of energy and mass balance of municipal solid waste pyrolysis.

Economic development and population growth lead to the increased production of chicken manure, which is a problematic organic waste in terms of its amount, environmental threats, and moisture content. In this study, hydrothermal carbonization, an emerging way of waste disposal, was performed on chicken manure to produce an energy-rich material called hydrochar. The effects of hydrothermal carbonization temperature (180, 240, 300 °C) and process time (30, 90, 180 min) were summarized. Proximate and ultimate analysis, as well as low and high heating values were applied both on raw material and derived hydrochars. Additionally, the performance of the process was examined. The obtained results show that hydrothermal carbonization is a feasible method for chicken manure disposal and valorization. Although the process time did not influence the fuel properties of chicken manure considerably, a higher temperature led to a significantly higher heating value, reaching 23,880.67 ± 34.56 J × g⁻¹ at 300 °C and 180 min with an improvement of ~8329 J × g⁻¹ compared with raw chicken manure (15,551.67 J × g⁻¹). Considering the energy gain value, the hydrochar derived at 240 °C in 30 min had the best result. Moreover, the energy consumption for this process was relatively low (124.34 ± 8.29 kJ × g⁻¹). With its still feasible fuel properties and high heating value of 20,267.00 ± 617.83 kJ × g⁻¹, it was concluded that these parameters of chicken manure hydrochar are the most beneficial and present a potential alternative for conventional fuel.

Intellectual capital is an overarching concept that includes the intangible, human-related factors that are relevant to the innovation process, such as human capital and social capital. In the present study, intellectual capital was assessed by indicators measuring different aspects of human and social capital. Factor analysis demonstrated the existence of three underlying factors, with all variables of the model having important contributions to them. A linear regression analysis indicated that 8 out of the 12 variables of intellectual capital used have a statistically significant impact on the measure of innovation output. These findings were discussed and their implications for policy were considered. The paper provides research evidence on the importance of intellectual capital for innovation output and discusses potential ways to achieve smart, sustainable and inclusive growth in the context of the next generation of sustainable smart specialisation strategies.

In the wake of economic and population growth, increased wastewater production poses a challenge related to sewage sludge treatment, which is problematic given its high moisture content, amount, and hazardous characteristics. This study focuses on the hydrothermal carbonization of sewage sludge to produce carbonous material–hydrochar, which may be an alternative to fossil fuels. The effect of process parameters, namely, temperature (180, 240, 300 °C) and duration time (30, 90, 180 min), on hydrochar properties (proximate and ultimate analysis, heating values) and process performance were studied. Obtained results indicate and confirm that hydrothermal carbonization, especially temperature increase, improves the fuel properties of carbonized sewage sludge. The highest low heating value was obtained for hydrochar derived at 300 °C in 180 min (~23 MJ × kg⁻¹). The highest energy gain was noted for hydrochar derived at 240 °C in 180 min (~23%). As well as relatively high mass and energy yield in comparison to other hydrochars, these parameters are considered the most favorable for sewage sludge hydrothermal carbonization. However, high energy consumption (over 1300 kJ × g⁻¹) suggests that more research on the process’s economical efficacy is required.

With the global population surpassing 8 billion in 2022 and projected to exceed 10 billion by 2058, municipal solid waste (MSW) generation presents a formidable challenge. One approach to manage MSW is Waste-to-Energy. This includes the conversion of MSW into carbonized solid fuel (CSF) through thermochemical processes. However, concerns regarding volatile organic compounds (VOCs) release from CSF during storage and use have arisen. Such release can pose potential health and environmental risks, yet the issue remains underexplored. This review critically evaluates VOC release from waste-derived CSF, namely carbonized refuse-derived fuel. It focuses on gaps in existing research, inconsistencies in VOC quantification methods, and regulatory challenges. Unlike existing studies that primarily examine process emissions, this review emphasizes the release of VOCs during storage and handling. A framework to integrate process-condition modeling and post-production release assessment was proposed to provide insights into mitigation strategies for VOC release reduction during storage and handling. Our findings highlight critical research gaps in VOC characterization, predictive modeling, and long-term exposure risks. This review emphasizes the need for standardized methodologies and stricter regulatory oversight in the management of waste-derived solid fuels.

Economic development and population growth lead to increased production of chicken manure (CM), which is a problematic organic waste for its amount, environmental threats, and moisture content. There are different ways of CM, namely anaerobic digestion, composting, combustion, and direct land spreading. Hydrothermal carbonization (HTC) is another emerging way, however. In this study, the HTC of CM was performed to produce energy-rich material called hydrochar (HC). The effects of HTC temperature (180, 240, 300 C) and process time (30, 90, 180 min) were summarized. Proximate and ultimate analysis, as well as heating values (HHV, LHV), have been performed both on raw CM and derived HC. Additionally, the process performance has been examined. The obtained results show that HTC is a feasible method for CM disposal and valorization. Although process time did not influence considerably fuel properties of CM, higher temperature led to significantly higher HHV, reaching 23,880.6734.56 Jg-1 at 300 C and 180 min with an improvement of 8,329 Jg-1 compared with raw CM (15,551.67 Jg-1). The process conducted at 240 C in 30 min has been specified as the most favorable, due to the highest energy gain of HC and relatively low energy consumption.