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Mineral oil has been used for many years in various electrical equipment, including transformers, as a cooling and insulation medium. However, its low biodegradability and poor performance in terms of fire protection have prompted the search for fluids to replace it, with vegetable oils being prominently considered. In this study, the dielectric, chemical, and physical properties of four vegetable oils obtained from different seeds (sunflower, rapeseed, soybean, and palm) and a biodegradable synthetic fluid are analysed throughout their lifespan in transformers. Their performances are compared with a traditional mineral oil to assess which one is more suitable for use in transformers employing this type of paper. To achieve this, the fluids were subjected to thermal ageing in combination with copper and a thermally upgraded kraft (TUK) paper, with its degradation controlled by measuring the degree of polymerisation. The results demonstrate that the origin of the vegetable oils affects their properties and degradation rates. It was found that most of the alternative fluids are suitable for use in transformers with the TUK paper and that they can increase their lifespan. [ABSTRACT FROM AUTHOR]

This paper describes the process used to produce thermoplastic building materials from non-recyclable mixed plastic–paper packaging waste. A first step was dedicated to an innovative and sustainable sterilization technology for non-recyclable waste, based on exposure to microwave radiation in closed air-circulation ovens. Further, composites with different cellulose contents and with two polymer matrices, respectively, were obtained using an injection process, and the samples were subjected to mechanical and physical tests. Due to their superior features, the products based on mixed polypropylene–paper packaging waste may successfully replace the classic polyvinylchloride-based wood–plastic composites. The environmental impact of mixed plastic–paper packaging waste was analyzed, and the sustainability of the thermoplastic technology was demonstrated from an economic and environmental point of view. [ABSTRACT FROM AUTHOR]

This article introduces the concept of ecological costs associated with the waste paper recycling system. The costs associated with this process include resource consumption, waste emissions, ecological damage, and production processes. To analyze the ecological costs of deviations from the baseline material flow in a waste paper recycling system, a benchmark material flow diagram is constructed using the material flow analysis method. The diagram illustrates a fully closed one-way material flow of the recycling system, which is highly abstracted and simplified. The study analyzed the ecological costs of the benchmark material flow and the impact of deviations from it. The results suggest that the circulation of materials within and between processes increases the ecological cost of the waste paper recycling system. Furthermore, the release of materials from a process into the environment also contributes to its ecological impact. However, the introduction of external materials into the recycling system can reduce its ecological impact, particularly if these materials are recycled resources. The study emphasizes the significance of considering ecological costs in waste paper recycling systems to minimize their environmental impact. [ABSTRACT FROM AUTHOR]

Labels are a crucial component of products, offering informational content and attractive visuals; therefore, the durability of the print is an important quality requirement. On the other hand, in accordance with eco-design, the recyclability of printed labels is vital. In our research, the focus was on the assessment of the durability, recyclability, and deinkability of printed label paper equipped with printed RFID tags. The determined color fastness of electrophotographic prints affected by various environmental factors showed good resistance to dry rubbing and, in most cases, light and moist–heat treatment, confirming the applicability of digital printing on self-adhesive biodegradable paper labels. In the second part of this study, recyclability was assessed, and a comparison between the deinkability of the offset and digital prints and two conductive functional inks was conducted. Good deinkability was observed for the printed RFID antennas on both the offset and electrographic prints, with only a small deterioration in optical properties, especially when nano-silver conductive ink was used. The study highlights the importance of the selection of materials and printing techniques when considering the environmental impact of printed electronics. The results showed that INGEDE 11 is a suitable deinking method for printed RFID antennas on offset and electrographic prints. [ABSTRACT FROM AUTHOR]

Packaging waste correct sorting hugely impacts fiber-based packaging circularity. Currently, this is more crucial than ever, also due to the increased market share of fiber-based packaging. This study evaluated the relationship between the aesthetic properties and user material sorting actions of lightweight dispersion-coated and uncoated paper substrates. Unlike previous literature, no labeling or graphics were involved in this study, focusing on the physical and aesthetic properties of both coatings and substrates. Untrained panelists participated in a multi-phase (descriptive and hedonic) analysis involving a questionnaire and antonym scales about samples' visual and tactile properties, which were also characterized. The results highlight a remarkable panelist's ability to assess the relative gloss and roughness. Perceived roughness and mattness statistically significantly correlated to cellulosic material identification. Moreover, material sorting into the paper recycling stream was statistically significantly regulated by sample mattness, followed by sample roughness. This work suggests that, without any graphic or textual information, the combination of substrate characteristics and coating formulation strongly impacts the packaging aesthetics, hence packaging perception as paper-based material. Consequently, the correct material identification and sorting can be encouraged by proper packaging materials selection and coating development. [ABSTRACT FROM AUTHOR]

The valorization of black liquor, a by-product produced in considerable quantities from the paper manufacturing processes, has demonstrated the effectiveness of thermal reconversion into pyrolysis gas, bio-oil, and bio-char, a sustainable approach placing the feedstock into a circular economy concept. The present study focused on developing disposal solutions through energy recovery via pyrolysis at 300 °C and 450 °C when lignite and nanomaterials (such as Cu-Zn-MCM-41, Ni-SBA-3, or Ni-SBA16) were used as catalysts. The results were compared to those of non-catalytic pyrolysis. The use of the Cu-Zn-MCM-41 catalyst proved to be efficient for pyrolysis gas production, reaching 55.22 vol% CH4. The increase in the calorific value of the pyrolysis gas was associated with the use of the Cu-Zn-MCM-41, showing a value of 42.23 MJ/m3 compared to that of the non-catalytic process, which yielded 39.56 MJ/m3. The bio-oil resulting from the pyrolysis with Cu-Zn-MCM-41 showed the highest energy value at 6457 kcal/kg compared to that obtained with the other two nanocatalysts, Ni-SBA-3 and Ni-SBA-16, as well as that of the raw material, which had a value of 3769 kcal/kg. The analysis of bio-char revealed no statistically significant differences when comparing the outcomes from using the various nanocatalysts, suggesting their minimal impact on the energy content. [ABSTRACT FROM AUTHOR]

Innovation in the circular economy (CE) and the deployment of effective circular business models (CBM) have attracted significant attention in times of growing natural resource scarcity. Despite this widespread interest, significant challenges remain between theoretical innovations and effective CBM implementation in any industrial sector where companies pursue cost-saving opportunities through waste valorisation strategies. Since current methods mislead in terms of the real limitations to designing feasible novel products and services under a circular economy, this study proposes exploring determinants underpinning the organisational resilience of CBMs under a resource efficiency strategy through three case studies. As a result of a co-creation process, the implementation of a CBM framework was built upon empirical data and, thence, a phase-based implementation guide was laid out to assist companies in designing and implementing innovative CBM dealing with the complexity of innovative waste valorisation strategies between the PPI and construction sectors. Relevant findings on managerial and policy recommendations encountered along the demo stage are provided in this paper favouring an effective implementation of CE strategies: the role of technological and non-technological aspects within the CBM, the perspective of the ecosystem and its value proposition, and specific guidelines for the different phases of CBM life cycle. [ABSTRACT FROM AUTHOR]

To reduce the pollution caused by paper sludge in the environment and overcome issues of poor water resistance and brittleness in Magnesium Oxychloride Cement (MOC), the MOC was modified by adding different dosages of paper sludge. The mechanical properties and damage modes of composite MOC materials containing paper sludge were studied by uniaxial compression tests. Under cyclic loading conditions, the damage progression of MOC composites was characterised using the tensile-shear conversion factor (Tsc) and by monitoring the energy parameters (elastic strain energy, plastic strain energy and dissipation energy). The results show that the average peak stress drop of MOC composites gradually increases with the increase in paper sludge dosage. Under uniaxial compression conditions, the Tsc of the MOC composites decreases from 0.99 to 0.44, and the damage mode is transitioned from brittle tensile damage to tensile-shear damage, X-shaped conjugate surface shear damage and finally to pure shear damage with an increase in doping. During cyclic loading conditions, the brittleness of MOC composites gradually decreases with an increase in paper sludge doping, which verifies the effect of paper sludge on the mechanical properties of MOC materials and the change in damage modes from the perspective of energy dissipation. [ABSTRACT FROM AUTHOR]

Some wastes from the paper pulp production process are still sent to a controlled waste landfill. These materials can constitute alternative resources for constructing road pavements. The study aimed to characterize and explore the sustainable application of two inorganic wastes resulting from the paper pulp process, the dregs (green liquor wastes) and the grits (slaker wastes), in the production of bituminous mixtures by the analysis of samples prepared with 5 and 10% of dregs and 5 and 10% of grits on the baseline reference bituminous mixture AC 14 surf 35/50. Some relevant mechanical properties of the blends were assessed based on Marshall compression, sensitivity to water and wheel-tracking tests. Additionally, water poured on the loose asphalt and compacted slabs' surface was analysed to determine the portion of harmful chemical compounds leached from the asphalt material. The results show that using dregs presented some technical limitations related to mechanical performance and that the incorporation of grits has an acceptable mechanical behaviour. Moreover, the study shows that the measured leachate resulting from water flow in a reference asphalt mixture and the blends with grits are insignificant. It can be concluded that using grits in asphalt mixtures is a promising technique regarding mechanical behaviour and environmental impacts that need further studies. [ABSTRACT FROM AUTHOR]

Melamine-impregnated paper waste (MIPW) is an unavoidable byproduct of the melamine-impregnated paper production process, and it must be urgently disposed. In this paper, due to its high N content, MIPW was used as a N source to co-pyrolyze with camellia oleifera shell (COS). By changing the proportion of MIPW in the raw materials, the migration path of the N was studied during the co-pyrolysis process. X-ray photoelectron spectroscopy (XPS), elemental analysis (EA), total nitrogen analysis (TN) and ultraviolet spectrophotometry were used to determine the content and the types of N-containing components in raw materials and products. The results showed that during the co-pyrolysis process, the N in MIPW and COS would be converted into different types of N-containing components, and the proportion of MIPW in raw materials directly impacts the product distribution and the N migration path. With the increase in the proportion of MIPW from 10 to 50 wt.% (daf, mass ratio), the proportion of N in raw materials that migrated into the solid phase decreased from 27.58 to 16.31 wt.%, while that which migrated to the gas and liquid phases increased from 24.92 and 47.50 wt.% to 25.97 and 57.72 wt.%, respectively. The proportions of N in the raw materials that changed into pyridinic-N, pyrrolic-N and graphitic-N in the solid phase and N2-N in the gas phase were decreased. The proportions of NH3-N and HCN-N in the gas phase and NH3-N and organic-N in the liquid phase were increased. Moreover, synergies were observed during the co-pyrolysis process, which affected the N migration path in the raw material. This study will provide policy directions and theoretical support for the comprehensive utilization of MIPW and COS. [ABSTRACT FROM AUTHOR]