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Seawater reverse osmosis (SWRO) desalination generates a concentrated brine byproduct rich in dissolved salts and minerals. This study presents an extensive economic and technical analysis of recovering all major ions from SWRO brine, which includes Na, Cl, Mg, Ca, SO₄, K, Br, B, Li, Rb, and Sr in comparison to conventional mining and chemical production of these commodities. Data from recent literature and case studies are compiled to quantify the composition of a typical SWRO brine and the potential yield of valuable products. A life-cycle cost framework is applied, incorporating capital expenditure (CAPEX), operational expenditure (OPEX), and total water cost (TWC) impacts. A representative simulation for a large 100,000 m³/day SWRO plant shows that integrated “brine mining” systems could recover on the order of 3.8 million tons of salts per year. At optimistic recovery efficiencies, the gross annual revenue from products (NaCl, Mg(OH)₂/MgO, CaCO₃, KCl, Br₂, Li₂CO₃, etc.) can reach a few hundred million USD. This revenue is comparable to or exceeds the added costs of recovery processes under favorable conditions, potentially offsetting desalination costs by USD 0.5/m³ or more. We compare these projections with the economics of obtaining the same materials through conventional mining and chemical processes worldwide. Major findings indicate that recovery of abundant low-value salts (especially NaCl) can supply bulk revenue to cover processing costs, while extraction of scarce high-value elements (Li, Rb, Sr, etc.) can provide significant additional profit if efficient separation is achieved. The energy requirements and unit costs for brine recovery are analyzed against those of terrestrial or conventional mining; in many cases, brine-derived production is competitive due to avoided raw material extraction and potential use of waste or renewable energy. CAPEX for adding mineral recovery to a desalination plant is significant but can be justified by revenue and by strategic benefits such as reduced brine disposal. Our analysis, drawing on global data and case studies (e.g., projects in Europe and the Middle East), suggests that metals and salts recovery from SWRO brine is technically feasible and, at sufficient scale, economically viable in many regions. We provide detailed comparisons of cost, yield, and market value for each target element, along with empirical models and formulas for profitability. The results offer a roadmap for integrating brine mining into desalination operations and highlight key factors such as commodity prices, scale economies, energy integration, and policy incentives that influence the competitiveness of brine recovery against traditional mining. Full article

Advancements in remote sensing technology have enabled the acquisition of high spatial and radiometric resolution imagery, offering abundant and reliable data sources for forest fire monitoring. In order to explore the ability of Sustainable Development Science Satellite 1 (SDGSAT-1) in wildfire monitoring, a systematic and comprehensive study was proposed on smoke detection during the wildfire early warning phase, fire point identification during the fire occurrence, and burned area delineation after the wildfire. The smoke detection effect of SDGSAT-1 was analyzed by machine learning and the discriminating potential of SDGSAT-1 burned area was discussed by Mid-Infrared Burn Index (MIRBI) and Normalized Burn Ratio 2 (NBR2). In addition, compared with Sentinel-2, the fixed-threshold method and the two-channel fixed-threshold plus contextual approach are further used to demonstrate the performance of SDGSAT-1 in fire point identification. The results show that the average accuracy of SDGSAT-1 fire burned area recognition is 90.21%, and a clear fire boundary can be obtained. The average smoke detection precision is 81.72%, while the fire point accuracy is 97.40%, and the minimum identified fire area is 0.0009 km², which implies SDGSAT-1 offers significant advantages in the early detection and identification of small-scale fires, which is significant in fire emergency and disposal. The performance of fire point detection is superior to that of Sentinel-2 and Landsat 8. SDGSAT-1 demonstrates great potential in monitoring the entire process of wildfire occurrence, development, and evolution. With its higher-resolution satellite imagery, it has become an important data source for monitoring in the field of remote sensing. Full article

The growing amount of waste worldwide requires new solutions for its management. Agricultural by-products account for almost 10% of the waste generated. One of them is sheep wool, a natural fibre with beneficial physicochemical properties. Currently, sheep wool production amounts to approximately 1–2 million tonnes per year, of which 60% is used in the manufacture of clothing. Nevertheless, it poses a considerable challenge in terms of disposal due to its keratin-rich composition and slow biodegradability. This review analyses the chemical and physical properties of sheep wool and assesses its potential as biomass based on its carbon content and other elemental components. This allows us to provide a critical comparative analysis of the main technological pathways for the use of waste sheep wool as biomass, including anaerobic digestion, pyrolysis, direct combustion and gasification. The review highlights both the opportunities and limitations of these processes, comparing sheep wool in terms of energy potential and carbon footprint with other biomass. The review shows that the calorific value of sheep wool (19.5 MJ/kg) is competitive with traditional plant-based biofuels and the use of waste sheep wool as biomass source can contribute to reduction in CO₂ emissions of 2.1 million tonnes per year. The use of sheep wool as biomass can not only contribute to waste reduction but also supports the goals of sustainable agriculture and climate neutrality. The selected methods may offer a new and effective way of reducing waste and allow all sheep wool produced to be introduced into the circular economy. Full article

Advancements in material science have allowed us to exploit the potential of new era for aircraft production. High-performance composites and alloys have allowed us to improve the performance and durability of aircraft, but they have become more and more precious with time. These materials can provide significant advantages in use but are costly, energy-intensive to produce, and their recovery and reuse has become a critical step to be addressed. Accordingly, a new approach in which end-of-life aircrafts represent unconventional mines rather than a disposal challenge is becoming increasingly relevant, providing access to high-value strategic raw materials and aligning with circular economy principles including European Green Deal and the United Nations Sustainable Development Goals. The complexity of dismantling and processing hybrid structures composed of metal alloys, ceramics, and advanced composites requires multiple approaches able to integrate chemical, mechanical, and thermal recovery routes. Accordingly, this review critically discusses the state of the art of the routes of end-of-life aircraft treatments, evaluating the connections between technology and regulation, and positions material recycling and reuse as central pillars for advancing sustainability in aerospace. Furthermore, this review provides a comprehensive reference for addressing the technical, economic, and policy challenges of waste management in aviation, contributing to broader goals of resource circularity and environmental preservation set forth by international sustainability agendas. Full article

The use of ammonia-fueled solid oxide fuel cells (NH3-SOFC) in shipping has emerged as a key area of research for advancing zero-carbon transportation. This study integrates and analyzes a novel ship design powered by NH3-SOFCs to quantify its environmental impact across its entire life-cycle, from production to disposal. A 200 TEU ammonia-fueled container ship operating on the Yangtze River is used as the reference vessel. Comprehensive technical analysis and modeling of the ship’s construction, operation, and Decommissioning stages are conducted. By utilizing life-cycle assessment and the ReCiPe 2016 method for calculations, 19 environmental impact indicators were obtained, weighted, and normalized. Life-cycle characterization results reveal that ecosystem and human health impacts are predominantly influenced by the operation stage. Thus, focusing on environmental protection measures and technological innovations during operation is crucial to mitigate these impacts. Conversely, resource depletion is mainly driven by the construction stage, underscoring the need for optimized design, production processes, and the use of eco-friendly materials to reduce resource consumption. A comparative analysis between diesel-powered and ammonia-powered ships shows that while ammonia SOFC ships have a slightly higher environmental load in terms of metal consumption, diesel-powered ships exhibit higher overall environmental loads in other impact indicators. This demonstrates the superior environmental and social benefits of ammonia SOFC ships compared to traditional diesel power systems. Full article

In wastewater treatment, sludge is generated during both the primary and secondary sedimentation processes. With the growing volume of wastewater, sludge production has increased accordingly. Prior to subsequent treatment or disposal, sludge dewatering is a critical step to reduce volume and improve treatment efficiency. The primary challenge lies in the removal of bonded water within the extracellular polymeric substances (EPSs) and the microorganism cells. In this study, electrochemical pretreatment was employed to improve sludge dewatering performance. The optimal electrochemical treatment was achieved at an electrode spacing of 2 cm, a stirring speed of 500 rpm, and an electrolyte (1 M calcium chloride, CaCl₂) dosage of 3 mL for 50 min. Subsequently, flocculation was conducted. Compared with the widely used polyacrylamide (PAM), polydimethyldiallylammonium chloride (PDMDAAC) achieved superior dewatering performance with less than half the dosage required. Under the combined treatment, the final moisture content of the sludge cake was reduced to 53.2%. These findings indicate that the combination of Fe/Ti-based electrochemical pretreatment and flocculation process is a promising and efficient strategy for deep sludge dewatering. Full article

Soil stabilization is a key process in geotechnical engineering, particularly for expansive clay soils that exhibit low strength and high volume-change potential. This study examines the use of waste tire powder (WTP) and autoclaved aerated concrete powder (ACP) as sustainable soil additives to improve mechanical performance while promoting sustainable waste recycling. Clayey soils from the Çorlu/Tekirdağ region were blended with varying proportions of WTP and ACP, and their properties were evaluated through Standard Proctor compaction, unconfined compressive strength (UCS), and California bearing ratio (CBR) tests. The results showed that UCS increased from 3.7 MPa to 4.5 MPa with 5% ACP, while CBR values rose from 21.3% to 29.8% with 17% ACP addition. Incorporating 2% WTP enhanced elasticity and reduced brittleness, although higher WTP contents (4%) lowered cohesion and strength. The optimum formulation, 2% WTP + 5% ACP, produced balanced improvements in strength, stiffness, and deformation resistance. The novelty of this research lies in establishing a hybrid stabilization mechanism that combines the elastic contribution of WTP with the pozzolanic bonding of ACP. Beyond technical improvements, recycling these industrial by-products mitigates environmental pollution, reduces disposal costs, and provides economic benefits. Thus, this study advances both the scientific understanding and practical application of sustainable soil stabilization. Full article

The selection of suitable sites for the disposal of radioactive waste constitutes a critical component of nuclear waste management. This study presents an original methodological proposal based on the Analytic Hierarchy Process (AHP), designed to support early-stage site screening for a near-surface repository in Italy. AHP could be used to identify appropriate locations, focusing on 51 areas that have already undergone a preliminary screening phase. These areas, included in the National Map of Suitable Areas (CNAI), were selected as they fulfill all the technical requirements (geological, geomorphological, and hydraulic stability) necessary to ensure the safety performance of the engineering structures to be implemented through multiple artificial barriers, as specified in Technical Guide N. 29. The proposed methodology is applicable in cases where multiple sites listed in the CNAI have been identified as potential candidates for hosting the repository. A panel of 20 multidisciplinary experts, including engineers, environmental scientists, sociologists, and economists, evaluated two environmental, two economic, and two social criteria not included among the criteria outlined in Technical Guide N. 29. Pairwise comparisons were aggregated using the geometric mean, and consistency ratios (CRs) were calculated to ensure the coherence of expert judgements. Results show that social criteria received the highest overall weight (0.53), in particular the “degree of site acceptability”, followed by environmental (0.28) and economic (0.19) criteria. While the method does not replace detailed site investigations (which will nevertheless be carried out once the site has been chosen), it can facilitate the early identification of promising areas and guide future engagement with local communities. The approach is reproducible, adaptable to additional criteria or national requirements, and may be extended to other countries facing similar nuclear waste management challenges. Full article

As a solid waste generated during the desulfurization process of coal-fired power plants, the output of desulfurization dross is increasing year by year. If not properly treated, it may occupy land and potentially pollute the environment. This article reviews the physicochemical properties of desulfurization dross and the progress in its resource utilization. It specifically focuses on the application potential of semi-dry desulfurization dross, emphasizing how its comprehensive resource utilization can reduce environmental pollution and generate considerable economic benefits for related industries. It should be noted, however, that the leaching of heavy metals and the strong alkalinity of desulfurization dross may pose environmental risks such as soil and groundwater contamination. Current research still requires further improvement in the systematic assessment and management strategies of these risks. This review highlights the need to optimize pretreatment technologies for stabilizing desulfurization dross and enhance environmental risk management, to facilitate its large-scale and high-value utilization. This article also looks toward the research directions for semi-dry calcium-based desulfurization dross in the future, aiming to provide a reference for the sustainable development and environmental protection of semi-dry desulfurization dross. Full article

Replacing the linear process based on production, consumption, and disposal gives rise to the circular economy, in which materials are reincorporated into a new production process to create new amendments, following the model of sustainable agriculture. Through the circular economy approach, the aim is to add value to the waste generated during the adsorption process by recovering and reusing it as sustainable soil amendments. The present study analyzes the effects of saturated dolomitic calcareous amendment (DCAS) on the chemical properties of sandy-textured and clayey-textured agricultural soils. For this purpose, the dolomitic calcareous amendment, saturated with nutrients from hydroponic effluent through an adsorption process, was reused, and its effects on the chemical properties of agricultural soils were evaluated during incubation periods of 30, 60, and 90 days and compared with other amendments. A completely randomized experimental design was used, applying 4 treatments with 5 replications, totaling 20 experimental units for each soil type (sandy and clayey): T1 (control), T2 (dolomitic calcareous amendment in natura—DCAN), T3 (saturated dolomitic calcareous amendment—DCAS), and T4 (granulated dolomitic calcareous amendment—DCAG). The chemical properties evaluated were: pH in water, exchangeable aluminum, exchangeable calcium and magnesium, and available phosphorus. An interaction test between treatments and incubation periods was performed for each soil type and analyzed through analysis of variance, with means compared using Tukey’s test (p < 0.05) in InfoStat software, version 2020I. Through statistical analysis, it was confirmed that there was both interaction and a time effect for the variables pH, exchangeable aluminum, and available phosphorus in both sandy and clayey soils. Furthermore, the results showed that the saturated dolomitic calcareous amendment—DCAS (T3)—had good compatibility with both soil types, highlighting its ability to improve soil chemical properties by increasing pH, and available phosphorus levels, as well as completely reducing exchangeable aluminum concentration. This indicates that the saturated dolomitic calcareous amendment (DCAS) derived from the adsorption of nutrients from hydroponic effluent, can be effectively used to amend soil chemical properties, thereby promoting more efficient and environmentally sustainable agriculture. Full article

An integrated approach to waste management is based on efficient and safe methods for waste prevention, recycling, and safe waste treatment. In accordance with these principles, in this study, non-hazardous aluminosilicate waste (dust and sand) was used in the solidification/stabilization (S/S) treatment of hazardous waste (coating, emulsion, and sludge) from the automotive industry. Also, the oily component of the waste was valorized and investigated for energy recovery through co-incineration. The two S/S processes were proposed and their sustainability was assessed by utilizing all types of waste generated in the same plant, obtaining stabilized material suitable for safe disposal and oil phases for further valorization, and by techno-economic analysis. The efficiency of the S/S processes was evaluated by measuring unconfined compressive strength, hydraulic conductivity, density, and the EN 12457-4 standard leaching test of S/S products, along with XRD, SEM-EDS, and TG-DTG analyses. The possibility of using the oil phase was assessed based on its calorific value. The techno-economic assessment compared the investments, operating costs, and potential savings of both treatment scenarios. The results show that an integrated approach enables safe waste immobilization and resource recovery, contributing to environmental protection and economic benefits. Full article

Government-managed urban green spaces in Bangkok produce large quantities of leaf waste, which are typically sent to landfills, incurring considerable costs. This study assessed a novel method for valorizing this waste by converting dried, ground leaf material into compressed planting blocks (PL) to serve as a soil substitute. Annual leaf waste data from three government agencies were used to estimate production capacity and inform economic modeling. Agronomic trials with Mitragyna speciosa (Korth.) Havil. compared PL, coconut fiber (PC), and mixed soil with fertilizer over eight weeks in controlled nursery conditions. The results indicated that PL supported plant growth with a final mean height of 20.10 ± 2.01 cm, similar to PC (20.70 ± 1.90 cm) and significantly greater than soil (14.40 ± 1.50 cm) (p < 0.001). Economic analysis showed high net present values (THB 9.16–13.76 million) and very short payback periods (less than 0.08 years). The process proved technically feasible and profitable, while also reducing waste disposal costs, minimizing landfill emissions, and providing a cost-effective, biodegradable planting medium. This method presents a scalable solution for sustainable organic waste management in tropical urban areas, supporting several Sustainable Development Goals and advancing the circular bioeconomy. Full article

Electronic waste is becoming a growing global pollution issue due to short device lifespans and insufficient safe disposal methods. Hazardous metals like arsenic and mercury from electronic waste harm both the environment and human health. Recycling processes remain underdeveloped, requiring new eco-friendly solutions. This paper reports on the synthesis and properties of the cationic surfactants ammonium terthiophene (CTT) and 3,4-propylene-dioxythiophene (C-ProDOT), which may have potential use in organic electronics. Ecotoxicological tests showed no significant long-term toxicity and medium-to-high biodegradability, which are keys for environmental protection. These surfactants also displayed selective bacterial adhesion, making them candidates for bionic devices. Life cycle assessment revealed higher energy use and ecotoxicity for C-ProDOT than CTT, underscoring the need for sustainable chemical design. Full article

This study evaluates the viability of water jig for removing the impurities from CDW and the concentration of concrete aggregates from mixtures containing 10%, 20%, and 30% impurities (brick and gypsum), simulating the materials commonly found in CDW. Laboratory-scale jigging tests were conducted in single-stage jigging, and the products were characterized based on density > 2.6 g/cm³, water absorption, shape factor, and bulk density to evaluate the separation performance. It was noted that dense fractions consistently achieved high purity with less than 1% impurities and a concrete content of more than 99% and that more than 80% of dense material was recovered. These results demonstrate that water jigging is a technically viable method for producing recycled aggregates of sufficient quality for reuse in concrete while also reducing CDW disposal by more than 40% and contributing to the sector’s carbon footprint reduction. The findings confirm that even a single-stage jigging process can provide high-quality recycled aggregates, offering a simple and effective route for CDW beneficiation. Full article

Agro-industrial residues can improve the fermentation quality of tropical forage grass silages when used as additives, but a systematic synthesis of their effectiveness is limited. This integrative review aimed to identify the main residues used as additives in silages and assess their effects on the fermentation process. Following the PVO (population, variable of interest, and outcome) protocol, searches were conducted in the Wiley Online Library, Web of Science, and SCOPUS databases, with no restrictions on language, time, or region. The guiding question was: “What are the main agro-industrial residues used as additives in the ensiling of tropical forage grasses?” Of the 1414 documents initially retrieved, 138 were selected after screening titles, abstracts, and keywords. After removing duplicates and full-text evaluation, 58 studies met the inclusion criteria. Brazil led in the number of studies (89.66%). Elephant grass (Pennisetum purpureum Schum.) was the most studied forage (34.21%). Citrus pulp (13.79%) and coffee husk (12.07%) were the most evaluated residues. The addition of residues promoted a reduction in pH (66.07%), ammonia nitrogen (71.74%), buffer capacity (57.14%), and the concentrations of acetic (52.17%), propionic (52.63%), and butyric (55.00%) acids. Lactic acid content increased in 32.76% of studies; gas and effluent losses decreased in 69.57% and 86.36% of cases, respectively. Citrus pulp and coffee husk are the most used residues, enhancing fermentation quality. It is concluded that the use of agro-industrial residues in the ensiling of tropical forage grasses has the potential to improve fermentation quality. Full article