Search Results (171)

The pulping and paper-making (P&P) industry is one of the world’s largest manufacturing sectors, yet it is plagued by high water/energy consumption and massive discharge of highly polluted wastewater. The effluents from pulping, bleaching and papermaking processes are characterized by high chemical oxygen demand (COD), intense color, toxic adsorbable organohalides (AOX) and abundant refractory lignin, which pose significant threats to aquatic ecology and human health. Although conventional physical, chemical and biological treatments have been widely applied, they are constrained by insufficient degradation efficiency toward recalcitrant organics, high cost and potential secondary pollution. In recent years, electrocatalytic technologies including electrocatalytic oxidation, electroreduction and their integrated processes, have demonstrated superior efficacy in specific scenarios of P&P wastewater treatment, such as lignin degradation, toxic side-streams treatment, pretreatment for enhancing biodegradability, and polishing steps in integrated treatment systems, which are not universally applicable solutions for P&P wastewater remediation. Meanwhile, biomass fuel cells typified by direct biomass fuel cells (DBFC) and microbial fuel cells (MFC) provide promising pathways for synchronous pollutant removal, energy production and resource recovery. Representative studies have reported COD removal efficiencies of 60–100% for electrochemical and advanced oxidation processes, while integrated electro-Fenton–biological treatment increased the BOD/COD ratio from 0.34 to 0.52 and achieved an overall COD removal of 94%. It should be noted that these advanced electrochemical technologies are still confronted with challenges in industrial scale-up, high energy and electrode material costs, and stable continuous operation. This review systematically elaborates on the physicochemical properties, generation mechanisms and environmental impacts of P&P wastewater, comprehensively summarizes the mainstream treatment technologies including physicochemical, biological, electrochemical and integrated processes, and analyzes their reaction mechanisms, efficiencies and applicable conditions. Particular emphasis is placed on electrocatalytic treatment and bio-electrochemical valorization strategies. This review is anticipated to provide a valuable reference for the efficient and targeted treatment as well as sustainable utilization of P&P wastewater, thereby supporting the green and low-carbon development of the P&P industry. Full article

The treatment of high-salinity wastewater generated from the use of sodium hydroxide (NaOH) in rare-earth metallurgy poses significant environmental and resource-recovery challenges. Conventional methods are often economically unfeasible due to their high energy consumption and limited value recovery. To address these limitations, this study proposes an innovative integrated electrochemical process designed not only to desalinate the wastewater efficiently but also to valorize it through the simultaneous co-production of NaOH, chlorine (Cl₂), and hydrogen (H₂). Systematic optimization reveals a critical trade-off between ion transport efficiency and side reactions, with optimal performance achieved at 2 mol L⁻¹ NaCl, 80 mA cm⁻² current density, 2 mm electrode spacing, 30 mL min⁻¹ flow rate, and 5000 mg L⁻¹ initial NaOH concentration. The system maintains exceptional long-term stability, sustaining 97.5% Cl⁻ removal over 4410 min of continuous operation without membrane fouling, a key advantage over conventional processes. Validation with authentic rare earth wastewater achieves 90.3% desalination within 5 h. Techno-economic analysis shows that the market value of recovered NaOH nearly offsets the energy cost, achieving near-cost-neutrality. This work establishes electrolysis–membrane coupling as a technically viable and economically attractive strategy for transforming high-salinity industrial waste streams into valuable resources. Full article

The cosmetic industry represents a major sector of the global economy and is expected to significantly grow in the coming years. To enhance consumer acceptance and address increasing sustainability concerns, cosmetic companies are actively seeking innovative solutions to mitigate their environmental, economic, and social impacts. In accordance with this, several scientific studies focus on the development, scale-up, and life cycle assessment of sustainable cosmetic products, especially those derived from side streams in accordance with circular economy principles. Various reviews have addressed this topic; however, they typically cover one or two of these dimensions, providing only a partial perspective. In particular, existing studies mainly analyze the types of side streams used and the resulting products, often lacking a comprehensive framework that can effectively support the translation of these approaches into industrial-scale production. The aim of the present review is to address this gap by providing a comprehensive analysis of the maturity level of development, scale-up processes, and life cycle assessment of cosmetic products based on agro-industrial side streams. This analysis is intended to support companies in the transition towards more sustainable practices by reducing carbon footprint and limiting the intensive extraction of virgin raw materials. The different approaches and methodologies proposed for the development and scale-up of sustainable cosmetic products from agro-industrial side streams are also analyzed, considering whether life cycle assessment has been performed. Furthermore, the most suitable business models will be selected as innovative and sustainable value chains capable of generating economic benefits, fostering local development, and enhancing resource efficiency and supply security. Full article

The global wine industry generates approximately 20 million tonnes of organic residues annually, representing a significant environmental and management challenge. While phenolic compounds from winery by-products have been extensively studied, protein and peptide fractions remain underutilised. This review provides a systematic overview of proteins derived from major winery side streams, including grapevine leaves, stems, pomace, seeds, and wine lees, with emphasis on their characterisation and recovery. Conventional and emerging extraction strategies are evaluated, with particular attention to green technologies such as ultrasound-assisted extraction (UAE), pulsed electric fields (PEF), and natural deep eutectic solvents (NADES) in the context of sustainable and resource-efficient processing. Enzymatic hydrolysis is discussed as a key approach for converting complex proteins into bioactive peptides with antioxidant, antimicrobial, and antihypertensive properties. Potential applications in agriculture, plant protection, animal nutrition, and food systems are considered, together with the implications of the EU circular economy regulatory framework. Overall, winery by-products are highlighted as promising nitrogen-rich secondary resources, and the review outlines valorisation pathways supporting nutrient recycling, waste reduction, and the development of a more sustainable agricultural bioeconomy. Full article

Industrial zinc borate is commonly produced through a hydrothermal process using boric acid and zinc oxide as raw materials. In this study, zinc borate was synthesized by replacing boric acid with borax ore and fresh water with borax plant wastewater in order to improve resource efficiency and water sustainability within an industrial symbiosis framework. Due to side reactions originating from borax, the reaction medium exhibited high ionic strength, and the synthesis was completed at 90 °C in approximately 5 h, slightly longer than conventional industrial processes. An additional washing step was applied to reduce impurities, resulting in a final impurity level of 2966 mg/kg, comparable to that of commercial zinc borate. The use of borax plant wastewater significantly reduced fresh water consumption. However, the formation of a by-product stream containing approximately 16% Na₂SO₄ may limit direct industrial applicability. If this sodium sulfate stream is valorized within an industrial symbiosis framework, zinc borate production from borax and wastewater could represent a cost-effective and sustainable alternative to conventional processes. Full article

The expansion of the global agri-food industry has led to the generation of large volumes of processing by-products that, although traditionally treated as waste, represent valuable sources of bioactive phytochemicals with potential for sustainable valorisation. This review critically examines the integration of fruit, vegetable, cereal, and dairy processing side streams into functional dairy products. Particular attention is given to recent advances in green and emerging extraction technologies, including ultrasound-assisted extraction, microwave-assisted extraction, and supercritical fluid extraction, with emphasis on their efficiency, environmental performance, and effects on the stability and recovery of phytochemicals. The review also discusses the health-related properties of these bioactive compounds, including antioxidant, anti-inflammatory, and metabolic regulatory effects, in relation to their incorporation into milk, yogurt, cheese, and ice cream matrices. In addition, key barriers to industrial implementation are assessed, including compound stability, sensory constraints, bioavailability, and current regulatory limitations. Beyond direct fortification, the review also considers broader valorisation pathways, such as the biotechnological production of microbial enzymes from agro-industrial biomass, as relevant strategies for supporting circularity. Overall, this review highlights how sustainable extraction approaches and functional dairy innovation can contribute to improving the nutritional value, resource efficiency, and circularity of the dairy sector. Full article

The global seafood industry generates millions of tons of by-products each year, creating environmental and economic challenges but also presenting a valuable opportunity for resource recovery. These by-products, rich in bioactive compounds such as proteins, omega-3 fatty acids, collagen, chitin, and antioxidants, have traditionally been underutilized due to inefficient and energy-intensive conventional extraction processes. Pulsed electric field (PEF) technology has emerged as a promising, non-thermal, and environmentally friendly method for valorizing seafood by-products by enhancing the permeability of biological membranes through electroporation, thereby facilitating the efficient extraction of high-value compounds. This manuscript critically reviews the scientific principles underpinning PEF, including dielectric breakdown and transmembrane potential generation, and explores its mechanisms for improving mass transfer during extraction and dehydration. Applications of PEF for recovering proteins, lipids, and antioxidants from diverse seafood side streams are comprehensively discussed, with emphasis on its advantages such as reduced energy consumption, preservation of thermolabile compounds, and improved product quality compared to conventional methods. Despite demonstrated laboratory-scale successes, industrial adoption of PEF remains limited due to challenges in process optimization, economic feasibility, and regulatory frameworks. This review synthesizes current knowledge and provides guidance for future research to advance the industrial implementation of PEF as a sustainable and efficient tool for seafood by-product valorization. Full article

Elevator fault diagnosis heavily relies on high-precision sensing of microscopic physical states. Although Micro-Electro-Mechanical System (MEMS) sensors can capture such subtle features, they are constrained by high-frequency data streams, environmental noise, and the semantic gap between raw sensor data and actionable maintenance decisions. This study proposes a collaborative edge–cloud intelligent diagnosis framework specifically designed for elevator systems. On the edge side, a lightweight temporal Transformer model, ELiTe-Transformer, was designed and deployed on the Jetson platform. This model enhances sensitivity to event-driven MEMS signals through an industrial positional encoding mechanism and by integrating linear attention and INT8 quantization techniques, achieving a real-time inference latency of 21.4 ms. On the cloud side, retrieval-augmented generation (RAG) technology was adopted to integrate physical features extracted at the edge with domain knowledge, generating interpretable diagnostic reports. The experimental results show that the overall accuracy of the system reaches 96.0%. The edge–cloud collaborative framework improves the accuracy of complex fault diagnosis to 92.5%, and the adoption of RAG reduces the report hallucination rate by 71.4%. This work effectively addresses the bottlenecks of MEMS perception in elevator fault diagnosis, forming a closed loop from micro-signal acquisition to high-level decision support. Full article

The European Environment Agency believes that circular economy strategies could substantially contribute to CO₂ emissions reduction. Therefore, it is necessary that the agro-industrial sector identifies sustainable technologies for side-stream management. The scope of this review was to compare the sustainability of available biological treatments for by-product biomasses and organic waste. A total of 147 studies, all Life Cycle Assessments (LCAs) and Techno-Economic Analyses (TEAs), were selected through PRISMA-ScR methodology, on Scopus and Web of Science, and were bibliographically mapped on VOSviewer (Version 1.6.20) Anaerobic digestion and integrated energy recovery systems were found to be the most environmentally robust options. Integrated biorefineries and multi-product systems have emerged as the highest long-term sustainability potential, especially when process integration and co-product recovery were also implemented. Importantly, the most sustainable systems were found to have required considerable start-up investments. Thus, sustainable deployment of biological treatment technologies was clearly dependent on time-consistent policy frameworks that have been fertile to capital-intensive infrastructures via incentives and fiscal measures and that have embraced circular bioeconomy systems. Finally, this paper has demonstrated that the sustainability of biological treatments has resulted from optimal relationships between biomass characteristics, system boundaries, process integration, and market value of co-product, while no single technology has been sufficient in isolation. Full article

Yeasts such as Cutaneotrichosporon oleaginosum can convert low-value side streams into single-cell oils with fatty acid profiles comparable to vegetable oils. Crude glycerol (CG), a byproduct of biodiesel production, offers a cost-effective substrate, but its variable impurity load often causes strong growth inhibition. In this study, two untreated industrial CG batches were characterized and evaluated in 2.5 L and 19 L stirred-tank fermentations. Direct batch cultivation on CG resulted in no measurable growth, whereas an adapted stepwise feeding strategy effectively mitigated early inhibition and restored biomass formation, metabolic activity, and lipid accumulation. In 2.5 L cultivations, apparent growth rates up to 0.51 h⁻¹ and volumetric productivities up to 0.22 g L⁻¹ h⁻¹ were achieved, with lipid contents of ~30% and oleate-dominated fatty acid profiles. Fatty acid profiles remained oleate-dominated (~53–55% C18:1). Transition-scale (19 L) repeated-batch fermentations confirmed process robustness across > 640 h of operation, during which lipid content (~30–36%) and fatty acid composition (oleate ~51–53%) remained stable despite pronounced substrate-batch variability and increasing nitrogen limitation. These results demonstrate that untreated CG can be reliably valorized for lipid production using scalable feeding strategies without prior detoxification. This closes a gap between laboratory-scale feasibility studies and process-oriented, multi-cycle operation on industrial-grade feedstocks, confirming that feeding-driven inhibition control can ensure robust performance without substrate purification. Full article

This LCA study addresses the research gap concerning the comprehensive environmental implications of using paving block aggregates (PBA), derived from crushed waste concrete paving blocks (CPB), as a sustainable replacement for natural aggregates in cementitious materials. While the concrete industry faces twin challenges—high CO₂ emissions from cement and the massive ecological toll of extracting 20 Gt/year of natural aggregates—a systematic life cycle assessment of this specific waste stream was necessary, especially one that considered potential material interaction trade-offs. The study’s conclusions offer critical insight into achieving genuine sustainability. Consistently, cement production was identified as the overwhelming environmental hotspot, contributing over 90% of the global warming potential (GWP) across all scenarios. This finding indicates that even substantial changes in aggregate sourcing can only deliver limited GWP reductions unless accompanied by strategies targeting cement-related emissions. While substituting natural aggregates with PBA generally provided environmental benefits, a crucial trade-off was identified: the significantly higher dosage of superplasticizer required to maintain the workability of the PBA mixes. For mortar, the burden from the increased plasticizer became a major secondary hotspot, occasionally offsetting the gains from aggregate replacement. In these scenarios, the contribution of admixtures to the total GWP was sufficiently high to reduce or negate the environmental benefits achieved through aggregate substitution. In contrast, aggregate replacement proved more favorable in concrete than in mortar, as the concrete scenarios showed a weaker correlation between environmental impact and plasticizer use. The authors conclude that future strategies must prioritize reducing cement content and, critically, systematically consider the necessary use of admixtures to ensure that the intended environmental improvements are genuine and not counteracted by the side effects of material substitution. The quantified LCA results demonstrate that cement reduction offers the highest mitigation potential, while admixture optimization is essential to prevent secondary environmental hotspots, particularly in mortar applications. Full article

The sustainable processing of coffee requires not only improving the efficiency of conventional operations but also advancing the recovery and valorization of bioactive compounds across the coffee value chain. In this context, emerging technologies offer eco-efficient alternatives to conventional extraction methods. This review summarizes recent advances in ultrasound-assisted extraction (UAE), high-pressure extraction (HPE), cold atmospheric plasma (CAP), and microwave-assisted extraction (MAE) applied to coffee beans and major coffee side streams, including pulp, husk, parchment, silverskin, and spent coffee grounds. The physicochemical principles of each technology, the main operating parameters, and their influence on extraction yield, phenolic composition, antioxidant capacity, and heat-sensitive compound preservation are discussed. Furthermore, potential synergies between combined techniques (UAE-MAE or HPE-UAE) and trends toward industrial scaling and integral valorization within a circular economy framework are highlighted. Overall, the evidence indicates that emerging technologies can intensify coffee extraction processes, increase phenolic recovery (often achieving up to two-fold improvements in total phenolic content compared to conventional techniques), and significantly reduce processing times (commonly reaching 2.5–15 min), supporting more sustainable and industrially relevant value chains. Full article

The transition toward a circular, sustainable food industry requires efficient valorization of biological resources while minimizing environmental pressures. This critical review focuses on the sustainable use of bioactive compounds recovered from plant-based waste and side streams through green extraction technologies as a core element of circular economy strategies in the agri-food sector. By integrating EUROSTAT indicators, a multivariate analytical approach, combining correlation analysis, principal component analysis (PCA), K-means clustering, and agglomerative hierarchical clustering (AHC), was employed to assess the relationships between greenhouse gas emissions, energy productivity, economic activity, and environmental employment across European States. The results reveal two main structural dimensions that explain nearly 90% of the total variability, reflecting the balance between economic scale and environmental pressure, and the role of energy efficiency in supporting sustainable consumption. Cluster analysis identified converging economies with greater circularity potential and structurally distinct economies that require targeted transition pathways. These findings emphasize that circular bioeconomy solutions, such as integrating green-extracted bioactive compounds into food products, must be tailored to each country’s economic and energy profile. This review highlights the strategic role of circular economy principles in strengthening the sustainability, resilience, and innovation capacity of the European food industry. Full article

Agri-food industries generate substantial quantities of side streams such as peels, pods, seeds, and leaves. Traditionally regarded as waste, these by-products are now recognized as rich sources of bioactive compounds—often at higher concentrations than those found in edible plant parts. Their recovery reduces environmental impact and enables the development of sustainable ingredients for food and health-related applications, in line with circular economy principles. This study presents the design and metabolomic characterization of a novel lyophilized powder derived from Mediterranean and locally cultivated plant-based by-products (named BIOMEDER), including orange, lemon, olive leaves, carob pods, shiitake mushroom, and salicornia. A multiplatform metabolomics approach was applied, combining high-resolution UPLC-QTOF-MS, UHPLC-QTRAP-MS, SPME-GC-MS, and ¹H-NMR spectroscopy to comprehensively profile phytochemicals, nutrients, and volatile organic compounds (VOCs). The powder was found to be rich in flavonoids (e.g., luteolin-7-O-glucoside, hesperidin, eriocitrin), phenolic acids, amino acids (e.g., proline, GABA), organic acids (e.g., malic and citric acid), and over 40 VOCs associated with antioxidant and sensory functions. Notably, high concentrations of these compounds suggest potential health-promoting properties. These findings might support the formulation of a potential functional plant-based supplement and reinforce the value of integrating diverse agro-industrial by-products into sustainable, health-oriented food solutions. Full article

The integration of extended reality (XR) into industrial robotics requires robust middleware solutions capable of bridging heterogeneous systems, protocols, and user interactions. This paper presents a novel middleware framework designed to connect industrial robots with XR devices such as the HoloLens. The architecture employs a hybrid communication layer that combines MQTT (Message Queuing Telemetry Transport) and ØMQ (Zero Message Queue), leveraging the Sparkplug Robotics API model for robot data and publisher–subscriber streaming for XR camera feeds. A Redis cache database is introduced to ensure efficient data handling and prevent data corruption. On the robot side, the system is built on ROS 2 (Robot Operating System) and connects to proprietary industrial protocols through dedicated bridges, enabling seamless interoperability. Spatial alignment between physical robots and XR overlays is achieved using ArUco marker-based synchronization, while real-time kinematic and process data are visualized directly in XR. The middleware further supports bidirectional interaction, allowing users to adjust parameters and issue commands through XR devices. Beyond functionality, safety considerations are incorporated by integrating human–robot interaction safeguards and ensuring compliance with industrial communication standards. The proposed solution demonstrates how middleware-driven XR integration enhances transparency, control, and safety in robotic manufacturing processes, laying the foundation for greater efficiency and adaptability in Industry 4.0 environments. Full article