Search Results (9,389)

Lean Construction (LC) aims to enhance efficiency, minimize waste, and increase value in construction. However, its implementation is inconsistent, especially in developing countries like Jordan, due to a lack of assessment frameworks. This study examines the Lean Construction Knowledge Framework (LCKF) to assess LC capability in Jordan’s construction sector. A qualitative multiple-case study was conducted with three selected construction companies in Jordan, using semi-structured interviews and direct observation. A three-point scoring system evaluated 12 LCKF variables across three knowledge dimensions based on evidence from interviews, observations, and documents. This exploratory study found that most LCKF variables were partially implemented or absent. Effective stakeholder communication was strong, while flow tracking, visual management, and Key Performance Indicators (KPIs) were descriptive and not improvement-oriented. Deficits included a lack of formal training in waste reduction, visualization, and pull-based control, as well as inconsistent adoption of pull planning. A cross-case analysis confirmed shared gaps among the companies, indicating broader challenges in similar contexts. Based on the scoring results and follow-up interviews feedback, the LCKF was translated into a Jordan-specific roadmap that distinguishes between established practices, short-term enhancements, and long-term capability development. The study contributes by highlighting that LC implementation depends on tool adoption, organizational routines, learning mechanisms, and staged capability building. Full article

Break-bulk cargo operations are characterized by high variability and complex resource synchronization, yet they have received limited research attention compared to containerized logistics. This paper proposes an integrated lean-informed simulation framework for evaluating vessel service time (VST) in multipurpose terminals handling break-bulk cargo. The framework sequences three analytical stages: Value Stream Mapping paired with Ohno’s waste taxonomy to diagnose non-value-adding activities, a discrete-event simulation model built in Simio to quantify their impact on VST, and Sobol sensitivity analysis to decompose the remaining variability across operational factors. Demonstrated at DP World Lirquén, a multipurpose terminal in Chile, the lean diagnostic identified 101 min of waste per cycle across waiting, motion, and overproduction categories. Scenario evaluation showed that eliminating shift-transition delays and standardizing load composition reduced VST by 14.3% and 10.6%, respectively, without capital investment. The sensitivity decomposition revealed that warehouse machinery composition, particularly the interaction between equipment types, dominates VST variability, while truck fleet size operates as an independent factor. These findings demonstrate that coordination-related policy interventions outperform incremental resource additions. More specifically, machinery allocation must be optimized jointly rather than by equipment type in isolation. Full article

This study examined how exposure to constructive audiovisual news shapes people’s perception of societal issues in the Netherlands. An online experiment was conducted among 575 participants aged 18 to 90 years old. Participants were randomly assigned to watch an audiovisual news item, either constructive or nonconstructive news, about plastic waste in the ocean or the Dutch housing market. The study investigated how these different reporting styles affected participants’ perceptions of the main message, their awareness of the seriousness of the societal issue, and their evaluation of the journalistic quality of the news report. Results showed that, contrary to critics’ concerns, constructive news did not reduce perceived problem awareness: participants across conditions reported similarly high levels of awareness regarding the seriousness of the issues presented. Perceived journalistic quality also remained high in both constructive and nonconstructive conditions, indicating that incorporating constructive elements did not compromise credibility. Furthermore, constructive news appeared to encourage a broader, more solution-oriented perspective, prompting participants to consider opportunities and future prospects. Importantly, this broader perspective did not come at the expense of perceived problem awareness or journalistic quality. Overall, the findings provide empirical support for the value of constructive journalism in the Dutch media context. Full article

Municipal solid waste (MSW) management is a critical challenge to advancing recycling and circular economy approaches. This review provides a comprehensive overview of MSW management, encompassing sourcing, policy frameworks, characterization techniques, separation technologies, preprocessing strategies, and utilization pathways. First, generation patterns and sourcing mechanisms are discussed in both U.S. and global contexts, with emphasis on the influence of policy frameworks on waste reduction and diversion. Second, characterization techniques are evaluated, focusing on physical and chemical analysis for material recyclability. Third, sorting technologies are critically reviewed, covering conventional methods and emerging sensor-based approaches. Preprocessing techniques are then evaluated for their role in improving downstream conversion efficiency. Finally, valorization pathways such as waste-to-syngas, waste-to-biochar, and waste-to-sustainable aviation fuel (SAF) are assessed in terms of their role in climate mitigation and the circular economy. It is anticipated that this review will provide a foundational reference for researchers, policymakers, and industry stakeholders aiming to strengthen the recyclability infrastructure and maximize the efficiency of MSW management systems in the framework of the circular economy. Full article

Surfactin is a lipopeptide biosurfactant with significant industrial potential, but high production costs have hindered its commercialization. In this study, we developed a sustainable and cost-effective bioprocess for surfactin biosynthesis using Bacillus subtilis 55033, utilizing kitchen waste as the primary fermentation substrate without any previous pretreatment—an advantage that simplifies the process and reduces costs compared to previous reports. To maximize productivity, the fermentation parameters were systematically optimized through single-factor and orthogonal experimental designs. The optimal conditions were as follows: a fermentation temperature of 31 °C, a duration of 48 h, a 5% v/v inoculum, a 7% w/v solid-to-liquid ratio, an initial pH of 7.5, and an agitation speed of 200 rpm. Under these conditions, the surfactin yield reached 371.67 mg/L, an increase of 100.5% from 185.4 mg/L prior to optimization. We performed a comparative analysis of the surfactin biosynthetic gene clusters between B. subtilis 55033 and the model strain B. subtilis 168. The produced surfactin exhibited potent antagonistic activity against aquatic pathogens, significantly inhibiting the growth of several species of Vibrio and the division and hatching of Cryptocaryon irritans Tomonts. These findings demonstrate that our platform not only provides a high-value valorization route for organic waste but also enables preliminary exploration of surfactin applications in aquaculture, in line with the principles of a circular bioeconomy. Full article

Fatigue and muscle wasting are common clinical manifestations of inherited and acquired neuromuscular disorders, including peripheral neuropathies, neuromuscular junction disorders, and myopathies. These conditions encompass a wide disease spectrum with variable prognoses, making accurate diagnosis essential for appropriate management. Congenital myasthenic syndromes (CMSs) are rare, inherited disorders characterized by impaired neuromuscular transmission. Although symptoms often begin in infancy or early childhood, later onset during adolescence or adulthood is increasingly recognized. Clinical phenotypes vary according to the underlying molecular defect, but fatigable weakness predominantly affecting axial and proximal limb muscles is a hallmark feature. We report an adolescent male who developed progressive proximal muscle weakness and wasting over several years, resulting in significant functional impairment. Initial evaluation suggested limb–girdle muscular dystrophy. However, comprehensive investigations, including whole-exome sequencing, identified a heterozygous CHRNB1 mutation consistent with postsynaptic CMS. Targeted pharmacological therapy led to clinical improvement. This case highlights the importance of considering CMS in patients presenting with limb–girdle weakness and underscores the value of genetic testing in establishing an accurate diagnosis and guiding treatment. Full article

Accurate and automated extraction of solid waste sites from remote-sensing imagery constitutes a pivotal demand for contemporary environmental regulation and risk mitigation. However, in high-resolution remote-sensing imagery, solid waste sites are typically represented as a single semantic image object (SIO), which is composed of multiple physical image parcels (PIPs) exhibiting significant variations in scale, morphology, and spectral properties. This intrinsic heterogeneity substantially increases the complexity and uncertainty of multi-class site identification. To address this challenge, this paper proposes WasteMOE Net (WMN), which is developed based on the core concept of modeling the SIO–PIP relationship. WMN adopts a heterogeneous expert selection mechanism combined with a nested mixture-of-experts architecture. It thus enables adaptive perception of complex PIPs across diverse scenarios and their integrated discrimination at the SIO level. In addition, by incorporating the explicit nonlinear representation capability of the KAN network, WMN effectively improves multi-class recognition accuracy while maintaining computational efficiency. Furthermore, this study constructs a high-resolution solid waste site dataset in accordance with the SIO–PIP-aware annotation principle, encompassing five representative categories: tailings ponds (TP), construction spoil sites (CSS), landfill sites (LS), garbage dump sites (GDS), and excavation sites (ES). Experimental results show that WMN achieves mAP50 values of 74.2% (GDS), 63.5% (CSS), 80.9% (ES), 85.4% (TP), and 83.1% (LS) in detection tasks, and 75.4%, 64.1%, 83.0%, 86.7%, and 84.1% for the corresponding categories in segmentation tasks. It achieves competitive performance compared with state-of-the-art methods in both tasks. Further, in a real-world application over Loudi City, China, WMN completed the processing of a 490.67 km² area within 1.34 h. The recognition accuracies for GDS and ES reached 54.8% and 65.3%, respectively. Finally, the proposed method has been successfully integrated into a GIS-based solid waste pollution risk prevention system, which markedly boosts the overall efficiency of environmental monitoring and on-site inspections. Full article

Admiralty brass, commonly used in heat exchangers, is particularly susceptible to corrosion in acidic media such as those used in industrial cleaning. To mitigate this problem, the present study evaluated Musa acuminata (banana) peel and Lupinus mutabilis Sweet (Andean lupine) extracts as sustainable, low-toxicity corrosion inhibitors for admiralty brass in 0.5 M HCl. Six extracts were prepared using different solvents and characterized by qualitative and semi-quantitative phytochemical analyses (phenols, flavonoids, alkaloids). M. acuminata extracts were rich in phenolic compounds, while L. mutabilis extracts contained high levels of quinolizidine alkaloids. A comparative electrochemical screening of the agro-industrial waste-derived extracts revealed that the inhibition efficiency of M. acuminata extracts reached up to 43.6%, whereas the debittering wastewater extract of L. mutabilis (E6) achieved a maximum efficiency of 85.5% at 2000 ppm. A preliminary techno-economic analysis indicated the feasibility of industrial-scale production of the L. mutabilis-based inhibitor, yielding a net present value (NPV) of USD 9.48 million, an internal rate of return (IRR) of 27.3%, and a payback period of 6.7 years. These results demonstrate that agro-industrial residues can be valorized into effective and profitable green corrosion inhibitors, aligning with circular economy and sustainable chemistry principles. Full article

The mechanical properties and real-time damage evolution of sustainable concrete (SC) containing 100% recycled concrete aggregate (RCA) under the combined action of hybrid steel and polyolefin fibers were studied. Inspired by solving the massive effects on the environment from construction waste, as well as to improve the lower mechanical performance of lower-grade RCA, the effect of combining high-stiffness hooked-end steel fibers and flexible macro-polyolefin fibers within RCA was investigated. Six different mix designs were considered: plain, single-fiber (100% steel and 100% polyolefin) and three hybrid composites with varying fractions of the steel/polyolefin fibers (25/75, 50/50, and 75/25). Compressive, tensile and flexural strengths were determined by mechanical testing. During compressive testing, the damage evolution was monitored using low-cost acoustic emission (AE) as a non-destructive technique. Cumulative hits analysis, amplitude distributions, and the statistical b-value parameter were used for damage characterization. The results show that steel fiber significantly increased compressive strength (an increase of up to 13.8%), and the 50/50 hybrid mix showed a high synergistic effect, yielding the highest tensile (4.86 MPa) and flexural (25.54 MPa) strengths. AE analysis identified different damage fingerprints: Based on amplitude analysis, steel-fiber composites exhibited high-amplitude events (which may be attributable to fiber pull-out); polyolefin-fiber composites generated medium-amplitude events (may have resulted from distributed microcracking); and hybrid mixes displayed a mixed amplitude distribution. The b-value analysis provided insight into progressive damage and revealed that the hybrid fibers induce stable, diffuse damage that prevents the brittle failure of plain recycled aggregate concrete (RAC). The results show that hybrid fiber reinforcement can be a reliable approach to enhance the mechanical performance and crack resistance of RAC. Furthermore, low-cost acoustic emission (AE) serves as an effective non-destructive method for monitoring damage progression within the material. Full article

The exponential increase in photovoltaic panel (PV) waste highlights the urgent need to develop efficient and sustainable recycling processes. It is estimated that by 2030, 8 million tons of PV modules will reach their end-of-life stage, posing a significant environmental challenge and requiring the development of green technologies for resource recovery. This study assessed the performance of imidazolium-based ionic liquids (ILs) as “designer solvents” for the selective leaching of copper and silver from disused PV panels. Specifically, four quaternary imidazolium salts were evaluated: [Bmim]HSO₄, [Emim]HSO₄, [Bmim]Cl, and [Emim]Cl. Leaching tests were conducted on silicon wafers containing 0.28% Ag and 0.19% Cu under varying temperatures (25, 50, and 80 °C), IL concentrations (20% and 60% v/v), and hydrogen peroxide (H₂O₂) dosages (0% and 3% v/v) as an oxidizing agent. The results identified [Bmim]HSO₄ as the most effective leaching agent. The system achieved a maximum copper extraction of 96.70% at 60% v/v concentration and 80 °C. For silver, the highest extraction of 45.13% was obtained using [Bmim]HSO₄ at 20% v/v and 80 °C. The addition of H₂O₂ was crucial, demonstrating a clear synergistic effect with the imidazolium-based ILs by promoting oxidative dissolution. These findings confirm that imidazolium-based ionic liquids represent a promising and environmentally friendly alternative for the recovery of high-value metals in the circular economy of photovoltaic recycling. Full article

The valorization of phosphogypsum (PG), a byproduct of phosphoric acid production, along with waste glass (WG) and silica fume (SF) into value-added materials has attracted growing attention in recent years. The present study aims to synthesize three types of porous geopolymers (GD, GDP, and GDG) using Tunisian clay and locally available mineral wastes, and to investigate their potential as low-cost adsorbents for the removal of methylene blue (MB) dye from aqueous solutions. The physicochemical characteristics of the raw precursors and the resulting porous geopolymers were analyzed using various techniques, including FTIR, XRD, BET, and SEM. Variations in Si/Al, Na/Al, and Ca/Al ratios play a critical role in the geopolymer structure. The high Ca/Al ratio in GDP (porous geopolymer from calcined clay and phosphogypsum) promotes the formation of C-A-S-H, leading to increased macroporosity, which favors adsorption capacity despite the presence of a more heterogeneous morphology. The results indicated that the maximum adsorption capacity (Qmax) for MB dye was obtained for the GDP sample, reaching 68 mg/g. Adsorption experiments revealed the successful removal of MB dye by geopolymers, with the Langmuir isotherm and pseudo-second-order kinetic models adequately describing the adsorption process. The MB uptake by geopolymers was facilitated by weak physicochemical interactions, including electrostatic attraction, hydrogen bonding, and π–π interactions. This study proposes a simple and effective alkali activation strategy that combines different industrial wastes within a single geopolymer system, resulting in improved porosity and adsorption efficiency. Overall, the findings highlight the potential of these waste-derived geopolymers as promising and sustainable adsorbents for wastewater treatment applications. Full article

Steel dust is a waste generated during steelmaking in an electric arc furnace (EAF), which contains a high proportion of iron-bearing compounds, leading to the inclusion of this waste as a resource in the circular economy for steelmaking. In addition to the limitation related to granulation (the waste must be processed to obtain larger particle sizes), a limiting factor is the increasingly high Zn content due to the low-quality ferrous charge. For the recycling of steelmaking dust, preliminary processing is necessary to reduce zinc. The paper presents, in addition to qualitative characterization of steel dust, laboratory experiments on the compositional changes associated with zinc redistribution applying the hydrometallurgical leaching process in an alkaline environment, using sodium hydroxide (NaOH). The changes in the chemical composition were identified and evaluated using X-ray fluorescence (XRF) and energy-dispersive X-ray spectroscopy (EDX). The experiments consisted of treating steel dust samples with 5 M NaOH at 25, 70, 80 and 90 °C for 60 min, using solid-to-liquid ratios of 10, 15, and 25 g/L. The results indicate a reduction in ZnO content ranging from 4.52% to 16.82%, as determined from Na₂O-free normalization data. Room-temperature samples show only marginal changes in ZnO content. The XRF and EDX analyses indicate a moderate and condition-dependent redistribution of zinc in the solid phase after alkaline treatment, as evaluated using Na₂O-free normalized data. These values are derived exclusively from solid-phase measurements (XRF/EDX) and do not include zinc in the leachate; therefore, true zinc extraction efficiency cannot be determined. The research results attest to the viability and efficiency (as a solid-phase compositional transformation process) using NaOH as a leaching agent for the studied steel dust, thus providing a potential pathway for improved waste recycling in the steel industry. Full article

Global demand for sustainability drives interest in bioenergy from sustainable feedstock. Agro-industrial waste such as brewer’s spent grains (BSG) is an important by-product of brewing. This study provides a comprehensive review of the current technologies of BSG for energy recovery and BSG-based materials for energy storage applications. The latest scientific progress, not only from conventional processes on anaerobic digestion, combustion, gasification, pyrolysis, torrefaction, and hydrothermal liquefaction but also from several integrated technologies, pretreatment methods, and additives/catalysts regarding the improvement of energy efficiency and process sustainability, was reviewed. In addition, the co-feedstock practices (co-combustion, anaerobic co-digestion, hydrothermal co-liquefaction, anaerobic co-fermentation) and co-production were examined. AD of BSG yields about 302 NL CH₄/kg COD, generating roughly 0.39 kWh of electricity/kg BSG and 1.71 MJ of thermal energy/kg BSG. Ultrasonic pretreatment enhances methane production up to four times (107 L CH₄/kg TVS) and reduces CO₂ emissions by 0.083 t CO₂eq/t BSG. Anaerobic co-digestion of BSG with other brewery waste increased the yield up to 88 mL CH₄/g TVS, generated approx. 0.348 kWh/kg TVS electricity, and reduced emissions by 0.114 kg CO₂eq/kg TVS. Bioethanol yields can reach 72%, while biohydrogen generation was up to 5154 mL H₂/g glucose. BSG pyrolysis provides up to 71.8% bio-oil, and its calorific value is 18–25 MJ/kg. BSG-derived activated biocarbon has a notable surface area (1792 m²/g) for lithium–sulfur batteries. The assessment showed that BSG’s transformation into bioenergy and energy storage materials aligns with waste reduction and sustainable development goals. However, future research on combined alternative wastes, integrated technologies, green nanotechnology, and artificial intelligence technology could lead to optimal performance and facilitate their industrial application. Full article

The mining industry faces increasing challenges related to the growing volume of tailings generated during mineral processing. This study presents a case study of the Complex Mine Waste Reduction (CMWR) concept implemented at the Polkowice Concentrator operated by KGHM Polska Miedź S.A. The approach integrates coarse ore sorting with tailings reprocessing for construction material production. Sorting improves flotation feed quality by rejecting low-grade gangue, while reprocessing converts fine tailings into value-added products. The combined implementation reduces tailing deposition by up to 22% and improves the operational copper recovery in flotation while maintaining overall process recovery at an essentially unchanged level. The results demonstrate the potential of integrated solutions for sustainable and circular mining. Full article

Waste-to-energy (WtE) systems are frequently proposed as complementary waste-management strategies; however, their climate performance depends on the interaction between thermodynamic efficiency, material circularity, and electricity-system characteristics. Existing life-cycle assessments generally provide static comparisons between landfill and WtE but rarely identify the operating conditions under which WtE remains environmentally competitive. To address this gap, a parametric life cycle–energy framework was developed by integrating attributional LCA with an analytical energy model capable of evaluating critical efficiency thresholds under varying recovery rates and electricity-grid conditions. Four representative thermoplastics (PET, HDPE, PP, and LDPE) were evaluated using ReCiPe 2016 Midpoint (H) in SimaPro under Mexican electricity conditions ($E{F}_{\mathrm{grid}}=0.444$ kg CO₂eq/kWh). Results indicate that total life-cycle climate impacts are dominated by upstream polymer production, whereas end-of-life management contributes only marginally to overall GWP. Critical-efficiency analysis revealed strong sensitivity to both recovery rate and electricity-grid carbon intensity. For PET, the minimum efficiency required for WtE to outperform landfill increased from 13.1% to 73.5% across the evaluated scenarios, whereas HDPE remained competitive at efficiencies below 1.3%. Monte Carlo simulations (10,000 realizations) further demonstrated that avoided emissions decline systematically with increasing recovery rates, with LDPE exhibiting the highest mean avoided emissions (1735 kg CO₂eq) and PET the lowest (811 kg CO₂eq). These results demonstrate that WtE climate performance is governed primarily by residual waste availability and electricity-system evolution rather than thermodynamic efficiency alone. Consequently, WtE should be interpreted as a transitional residual-waste management strategy whose long-term climate relevance decreases as material circularity and electricity-grid decarbonization advance. Full article