Search Results (166)

Grape stems are undervalued winemaking by-products that constitute a promising source of bioactive phenolics with notable antioxidant potential and diverse industrial applications, including food preservation, cosmetics, and pharmaceuticals. Effective valorisation of this resource requires not only efficient extraction strategies, but also the strategic selection of grape stem varieties to tailor phenolic profiles for specific high-value uses. In this study, a comparative assessment of three extraction techniques, pressurized liquid extraction (PLE), ultrasound-assisted extraction (UAE), and conventional solid–liquid extraction (SLE), across six grape stem varieties was conducted. By integrating spectrophotometric analyses of total phenolics and antioxidant capacity with HPLC-DAD profiling of individual phenolic compounds, the combined influence of extraction method and varietal composition on phenolic recovery was demonstrated. PLE and UAE significantly enhanced both yield and antioxidant capacity relative to SLE, with PLE providing the broadest spectrum of phenolic compounds. Varietal differences were also pronounced; e.g., Cabernet Sauvignon stems yielded higher antioxidant phenolic compound content, particularly under UAE, reinforcing the importance of aligning extraction technique and stem variety with the intended functional application. Full article

The construction sector faces pressure to decarbonise while addressing rising resource demands and agricultural waste. Ordinary Portland cement (OPC) is a major CO₂ emitter, yet biomass residues are often open-burned or landfilled. This study explores corncob ash (CCA) as a sustainable supplementary cementitious material (SCM), examining how calcination conditions influence pozzolanic potential and support circular economy and climate goals, which have not been adequately explored in literature. Ten CCA samples were produced via open-air burning (2–3.5 h) and electric-furnace calcination (400–1000 °C, 2 h), alongside a reference OPC. Mass yield, colour, XRD, XRF, LOI, and LOD were analysed within a process–structure–property–performance–sustainability framework. CCA produced in a 400–700 °C furnace window consistently achieved high amorphous contents (typically ≥80%) and combined pozzolanic oxides (SiO₂ + Al₂O₃ + Fe₂O₃) above the 70% ASTM C618 threshold, with 700 °C for 2 h emerging as an optimal condition. At 1000 °C, extensive crystallisation reduced the expected reactivity despite high total silica. Extended open-air burning (3–3.5 h) yielded chemically acceptable but more variable ashes, with lower amorphous content and higher alkalis than furnace-processed CCA. Simple industrial ecology calculations indicate that valorising a fraction of global CC residues and deploying optimally processed CCA at only 20% OPC replacement could displace 180 million tonnes CC waste and clinker avoidance on the order of 5–6 Mt CO₂ per year, while reducing uncontrolled residue burning and primary raw material extraction. The study provides an experimentally validated calcination window and quality indicators for producing reactive CCA, alongside a clear link from laboratory processing to clinker substitution, circular resource use, and alignment with SDGs 9, 12, and 13. The findings establish a materials science foundation for standardised CCA production protocols and future life cycle and performance evaluations of low-carbon CCA binders. Full article

Heritage tourism is increasingly positioned as a strategy for revitalising rural communities, particularly in areas where structural transformations have changed traditional ways of life. However, its outcomes reveal a paradox. The same processes that preserve cultural landscapes often commodify them, converting living traditions into marketable symbols. This paper investigates this heritage paradox through a complex study of Viscri, a UNESCO-listed village in Transylvania, Romania. Combining demographic and occupational data (2002–2022) with 51 questionnaires, 7 semi-structured interviews, field observations, and local records, the study examines how tourism-driven heritage valorisation reshapes socio-economic structures and identity narratives. The results show a profound restructuring of livelihoods, with a marked decline in subsistence agriculture and the emergence of micro-entrepreneurial activities related to accommodation, crafts, and gastronomy. These changes, while improving local incomes and infrastructures, have also increased external ownership and redefined authenticity as a performative resource negotiated among residents, entrepreneurs, and visitors. Local voices oscillate between pride and fatigue, between preservation and loss. By conceptualising the heritage paradox as a dynamic interplay between conservation and commodification, this study contributes to global debates on authenticity, sustainable rural transformation, and community resilience, offering an empirically grounded model of heritage tourism’s ambivalent consequences through an original analytical lens for post-socialist rural contexts. Full article

The global production of electronic waste (e-waste) has increased due to the quick turnover of electronic devices, creating urgent problems for resource management and environmental sustainability. As a result, e-waste-derived materials (EWDMs) are being explored in pavement engineering research as sustainable substitutes in line with Sustainable Development Goals (SDGs), specifically SDG 9 (Industry, Innovation, and Infrastructure), 11 (Sustainable Cities and Communities), 12 (Responsible Consumption and Production), and 13 (Climate Action). Therefore, to assess global research production and the effectiveness of EWDMs in asphalt applications, this review combines scientometric mapping and systematic evidence synthesis. A total of 276 relevant publications were identified via a thorough search of Web of Science, Scopus, and ScienceDirect (2010–2025). These were examined via coauthorship structures, keyword networks, and contributions at the national level. The review revealed that China, India, and the United States are prominent research hubs. Additionally, experimental studies have shown that EWDMs, such as printed circuit board powder, fluorescent lamp waste glass, high-impact polystyrene, and acrylonitrile–butadiene–styrene, improve the fatigue life, Marshall stability, rutting resistance (up to 35%), and stiffness (up to 28%). However, issues with long-term field durability, microplastic release, heavy metal leaching, and chemical compatibility still exist. These restrictions highlight the necessity for standardised toxicity testing, harmonised mixed-design frameworks, and performance standards unique to EWDMs. Overall, the review shows that e-waste valorisation can lower carbon emissions, landfill build-up, and virgin material extraction, highlighting its potential in the circular pavement industry and promoting sustainable paving practices in accordance with SDGs 9, 11, 12, and 13. This review suggests that further studies on large-scale field trials, life cycles, and technoeconomic assessments are needed to guarantee the safe, long-lasting integration of EWDMs in pavements. It also advocates for coordinated research, supportive policies, and standardised methods. Full article

Coastal ecosystems represent a complex and dynamic interface for renewable energy development, combining solar radiation, coastal winds, and marine biomass. In regions such as La Guajira (Colombia), these resources create a unique opportunity to design hybrid systems that integrate solar, wind, and bio-based energy generation. This study applied a multicriteria assessment encompassing technical, economic, environmental, and social dimensions to evaluate the feasibility of this integration. The study adopts a narrative review approach supported by peer-reviewed literature, satellite-derived environmental datasets, and regional technical reports. Three criteria were used to assess the potential of these bioresources: (i) availability and spatiotemporal variability, (ii) physicochemical and energetic characteristics, and (iii) suitability for thermochemical and biochemical valorisation routes. Reported data indicate that pelagic Sargassum reaching the wider Caribbean contains 20–30% ash, 25–35% carbohydrates, and lower heating values between 8 and 12 MJ kg⁻¹, while cactus biomass in arid environments can reach LHV of 13–16 MJ kg⁻¹ and moisture contents below 15%. The coastal region of La Guajira also receives solar irradiation levels exceeding 6 kWh m⁻² day⁻¹ and wind speeds above 8 m s⁻¹, creating favourable conditions for hybrid bioenergy–renewable systems. Finally, the multicriteria analysis reveals that integrating coastal renewable resources could drive the transition towards a circular, inclusive, and low-carbon bioeconomy in coastal territories such as La Guajira. Full article

This study investigates the valorisation of piscindustrial by-products, specifically fishbones from mackerel, horse-mackerel, and sardines, as sustainable sources of multi-mineral ingredients (MMIs) for future dietary supplementation. Ground fishbone powders were first analysed for moisture content and total ash to establish baseline composition. Following these preliminary assessments, the samples underwent mineral profiling using microwave plasma atomic emission spectroscopy (MP-AES), enabling quantification of calcium, phosphorus, magnesium, iron, zinc, sodium, potassium, copper, lead, cadmium, selenium, chromium, tin, manganese, and mercury. All three species yielded high concentrations of essential minerals, supporting their relevance as upcycled nutritional resources. A sardine-based capsule formulation was developed and compared with a commercial calcium supplement through 240 min dissolution testing. While calcium release values differed significantly from 75 min onward, both formulations exhibited similar dissolution profile shapes, despite differing dosage forms. Statistical analysis confirmed time- and formulation-dependent effects, with the sardine capsule demonstrating enhanced calcium bioaccessibility in later phases (95.26 ± 10.11 vs. 78.79 ± 5.39 mg). This work contributes to the advancement of the United Nations Sustainable Development Goals (SDGs), particularly SDG 3, SDG 12, and SDG 14. By transforming marine waste into health-promoting ingredients, and enabling revenue streams for ocean-cleaning charities, this initiative exemplifies circular innovation at the interface of nutrition, sustainability, and marine stewardship. Full article

The agricultural sector faces significant challenges related to climate change and population growth, which intensify pressure on natural resources and food security. Sustainable resource-efficient systems, alongside wastewater valorisation, are a promising solution. This study evaluated the reuse potential of aquaculture, urban, and swine farm wastewater in hydroponic cultivation. Trials with leafy vegetables and fruit crops were conducted in aquaponic systems containing two fish species (Koi carp and African catfish) and two small-scale hydroponic systems. Water quality, plant development, and environmental parameters were monitored. Results for the best performance scenarios within each cultivation system showed that in urban wastewater, strawberries yielded 183 ± 74 g/plant, exceeding yields in aquaponics (125 ± 60 g/plant). Lettuce performed better in swine farm wastewater (180 ± 39 g/plant) than in urban (65 ± 6 g/plant), with corresponding water-use efficiencies of 117 and 65 g/L. Aquaponics also supported stable yields, up to 108 ± 1 g/plant for lamb’s lettuce and 10,047 ± 8791 g of papaya fruit per plant. Nutrient recovery in hydroponic systems supplied with urban and swine farm wastewater reached up to 95% for N, P, and K. Overall, these systems demonstrated substantially lower water consumption compared with values commonly reported for conventional agriculture, underscoring their strong sustainability advantages. Full article

The universal need for sustainable and renewable energy sources has accelerated the shift towards bioenergy as a valuable option to fossil fuels. However, a significant challenge remains in the underutilisation of biomass resources and the environmental pollution caused by improper biomass disposal methods. Biochar, a by-product of biomass pyrolysis rich with carbon, serves as a means to convert underused biomass into valuable energy and a tool for environmental remediation. Biochar can be integrated into a biorefinery for improved bioelectricity and biogas production, but there are challenges with regard to its production scalability, quality control, and standardisation. This article provides a comprehensive review of the prospective processes useful in the valorisation of biomass into biochar for bioenergy, co-firing potential with fossil fuels, and in waste biomass transformation. This article also provides insight into business development and policy-making by bioentrepreneurs, bioengineers, and the government, as it identifies grey opportunities for bioenergy production and improvement. The prospect of AI technology in improving the production, quality, and yield of biochar, by identifying the most efficient parameters and conditions, as well as optimising the application of biochar in various industries, is also highlighted. The transition to biofuels in aviation, a step towards a future in the industry that is more sustainable, is also suggested in this review. Full article

Mining activities have caused widespread land degradation and contamination, affecting millions of hectares worldwide and posing persistent ecological risks. However, reclamation substrates are constrained by limited availability and compromised quality, which restricts their ability to fully support mine ecological restoration. Among various amendment materials, biomass-based amendments have been widely applied due to their broad availability, renewability, biodegradability, and low cost. In recent years, their role has expanded beyond simple nutrient supplementation to encompass multiple functions, including structural optimization, pollutant stabilization, and microbial regulation. This review highlights the valorisation of biomass-derived solid wastes as multifunctional amendments for mine ecological restoration. By converting agricultural and industrial wastes into green materials, these amendments improve substrate structure, stabilize heavy metals and organic pollutants, enhance nutrient cycling, and stimulate microbial activity. Potential risks, including nutrient leaching, secondary pollution, and greenhouse gas emissions, are critically assessed, with emphasis on their variability under different environmental conditions. By integrating functional benefits with ecological risks, this work underscores the critical role of biomass-based amendments as waste-to-resource strategies in advancing sustainable mine reclamation, contributing to circular economy goals, and supporting environmental engineering practices. Full article

Expansive clay soils present major challenges for infrastructure due to their high swelling potential and low bearing capacity. While conventional stabilisers, such as lime and Ordinary Portland Cement (OPC), are effective, they are environmentally unsustainable due to their high carbon footprint. This study examines the potential of shredded recycled polyethene terephthalate (PET) fibres as a low-carbon alternative for stabilising high-plasticity clays. PET fibres were incorporated at dosages ranging from 0% to 1.2% by dry weight, and their influence on compaction characteristics, unconfined compressive strength (UCS), California Bearing Ratio (CBR), swelling behaviour, and microstructure was evaluated through laboratory testing and Scanning Electron Microscopy (SEM). Among the tested mixes, the 1.0% PET content exhibited the highest measured performance, resulting in a 37% increase in UCS, a 125% enhancement in unsoaked CBR, more than a two-fold increase in soaked CBR, and a 15% reduction in the Differential Free Swell Index (DFSI). SEM analysis indicated the formation of a three-dimensional fibre matrix, which improved particle interlock and reduced microcrack propagation. However, higher fibre dosages caused agglomeration and macrovoid formation, which adversely affected performance. Overall, the findings suggest that the inclusion of PET fibres can enhance both geotechnical and environmental performance, providing a sustainable stabilisation strategy that utilises plastic waste while reducing reliance on OPC. Full article

This work presents a preliminary “Strengths, Weaknesses, Opportunities, and Threats” (SWOT) analysis followed by a “Correct, Adapt, Maintain, and Explore” (CAME) analysis on wood sawdust biofuel. New designs of sawdust biofuels boilers and reactors require gathering relevant information on the main characteristics of sawdust biofuels. Optimisation algorithms require not only the numerical parameters needed to find optimal solutions but also the consideration of scenarios related to the use of this type of biofuel. This work provides complementary information to create a comprehensive framework for assessing the viability and sustainability of integrating wood sawdust into diverse energy production systems. This includes an examination of the current state of sawdust utilisation, its environmental implications, and the potential of valorising this abundant biomass resource. This review further delves into the technical aspects of converting sawdust into biofuel pellets, examining various technical processes involved in its physical analysis. The intended audience of this review encompasses researchers, mechanical designers, policymakers, and industry strategists and stakeholders interested in sustainable energy solutions and waste management strategies, providing a holistic perspective on the opportunities presented by wood sawdust as a renewable energy source. Full article

Intangible Cultural Heritage (ICH) is increasingly recognised as a potential factor that can strengthen social cohesion and societal resilience. Yet, existing scholarship often valorises ICH without fully examining the challenges, exclusions, and political tensions it can produce. This article addresses that gap by critically reviewing UNESCO frameworks, case studies, and academic literature to evaluate both the opportunities and the limitations of ICH in contemporary societies. Our analysis highlights how ICH can contribute to shared identity, intergenerational transmission, and adaptive ecological knowledge, while also noting the risks of standardisation, misappropriation, and nationalistic appropriation. Using a comparative and critical literature review approach, we synthesise examples from diverse contexts to illustrate the dual role of ICH as both a community resource and a contested political tool. The findings do not suggest that ICH universally or inevitably generates resilience or cohesion. Rather, they map the paradigms in which ICH has been mobilised for these purposes, showing both the potential benefits and the risks. On this basis, the article offers policy recommendations that emphasise community-led safeguarding, integration of traditional knowledge into resilience frameworks, and vigilance against exclusionary or exploitative uses of ICH. Full article

This paper investigates the design potential of post-consumer plastic waste through the Waste Driven Design (WDD) method, developed at IUAV University of Venice and implemented in both experimental and semi-industrial contexts. WDD proposes a situated and transdisciplinary approach, where waste is no longer regarded as a material to be discarded, but as a resource to be explored, transformed, and valorised. Using the Marble CAP case study—a new material derived from non-recyclable food packaging—the paper presents an iterative and scalable design process that combines technical experimentation, material storytelling, and application potential. The stages of the process are examined, from waste collection and cataloguing to the production of pressed sheets, which are tested under various conditions and finishes. The results demonstrate how, in design, material can become a catalyst for new aesthetics, languages, and production chains. Rather than concluding with the formal outcome, the project opens up spaces for critical and operational interventions along the supply chain, highlighting how design can contribute to imagining and activating alternative trajectories for waste transformation. Full article

The rising demand for sustainable agriculture and circular resource management has intensified interest in converting wastewater sludge into value-added products. This review explores the transformation of sewage sludge into slow- and controlled-release fertilizers (CRFs), with a focus on biochar production and encapsulation technologies. Sewage sludge is rich in essential macronutrients (N, P, K), micronutrients, and organic matter, making it a promising feedstock for agricultural applications. However, its use is constrained by challenges including compositional variability, presence of heavy metals, pathogens, and emerging contaminants such as microplastics and PFAS (Per- and Polyfluoroalkyl Substances). The manuscript discusses a range of stabilization and conversion techniques, such as composting, anaerobic digestion, pyrolysis, hydrothermal carbonization, and nutrient recovery from incinerated sludge ash. Special emphasis is placed on coating and encapsulation technologies that regulate nutrient release, improve fertilizer efficiency, and reduce environmental losses. The role of natural, synthetic, and biodegradable polymers in enhancing release mechanisms is analyzed in the context of agricultural performance and soil health. While these technologies offer environmental and agronomic benefits, large-scale adoption is hindered by technical, economic, and regulatory barriers. The review highlights key challenges and outlines future perspectives, including the need for advanced coating materials, improved contaminant mitigation strategies, harmonized regulations, and field-scale validation of CRFs. Overall, the valorisation of sewage sludge into CRFs presents a viable strategy for nutrient recovery, waste minimization, and sustainable food production. With continued innovation and policy support, sludge-based fertilizers can become a critical component of the green transition in agriculture. Full article

Global concerns about resource depletion, climate change, and nutrient pollution in aquatic systems are compelling a transition towards zero-waste industries. With the skyrocketing carbon footprint of the modern fertiliser industry, sustainable options are highly sought after. Anaerobic digestion of organic waste to generate renewable biogas and fertiliser production from the residual nutrient-rich digestate are promising nutrient recovery and recycling avenues. This review explores the potential use of anaerobic digestate to develop value-added agronomic products, focusing on the quality and safety parameters pivotal to its fertiliser value. A comprehensive review of conventional and cutting-edge technologies available for digestate processing into organic/organo-mineral fertilisers has been conducted, highlighting emerging sustainable approaches. Specifically, this review unravels novel aspects of enhancing digestate quality with biostimulants such as plant growth-promoting rhizobacteria, humic substances and biochar for biofertiliser/slow-release fertiliser production. Additionally, methods and guidelines to assess and address environmental impacts by digestate application on croplands and challenges in the commercialisation of digestate-based fertilisers were analysed. This review also underscores the importance of valorising anaerobic digestate as a fertiliser in implementing a circular bioeconomy within the agroindustry. Full article