Search Results (42,434)

The sustainability of rural areas depends on effective wastewater management to reduce human impact on the environment, including the risk of pollution to surface water, groundwater, and soil from human waste. However, organized sanitation systems, which include pipeline networks and wastewater treatment plants in rural communities with low population densities, often have very low profitability and cost-efficiency, which greatly reduces their acceptance and residents’ willingness to pay. This study examines the economic profitability and cost-efficiency of selected on-site household sewage collection and treatment systems operating under real economic conditions in Poland. An evaluation was conducted on seven contemporary models of individual bioreactors, as well as a standard anaerobic septic tank equipped with drainage filters. Additionally, all options were tested on permeable and poorly permeable soils. For each variant, investment costs, as well as operation and maintenance expenses, were calculated. Financial evaluation utilized indicators of economic profitability and cost-efficiency, including the Payback Period, Net Present Value, Benefits–Cost Ratio, and Dynamic Generation Costs. The potential financial benefits included savings from avoiding the use of holding septic tanks and sewage transport by slurry wagons. All the studied designs of on-site sanitary sewage management showed significant economic feasibility and cost-efficiency. Full article

Over 292 million tons of municipal solid waste (MSW) are generated annually in the United States, with more than half disposed of in landfills. Municipal solid waste landfills (MSWLFs) are stationary sources of air pollution and potential health risks for nearby communities. The Agency for Toxic Substances and Disease Registry (ATSDR) has completed over 300 public health assessments (PHAs) and related investigations at MSWLFs and open dumps since the 1980s. This paper reviews the ATSDR’s evaluations of air pathway concerns at 125 MSWLF sites assessed between 1988 and early 2025, with many being evaluated during the 1990s. Most sites were located in the Midwest and Northeast, and only 25% remained active. The ATSDR found no air-related public health hazard at 86% of sites. At sites where hazards were identified, common issues included elevated outdoor or indoor toxicants (e.g., hydrogen sulfide, benzene, trichloroethylene, and mercury) and unsafe methane accumulations. Contributing factors included older site designs, inadequate gas-collection, subsurface fires, and distance from nearby residences. Corrective actions effectively reduced exposures at the affected sites. Results suggest that well-located and maintained landfills minimize public health hazards, while aging or poorly managed sites pose risks. Continued monitoring and research are warranted as waste management shifts toward reducing, reusing, recycling, composting, and energy-recovery technologies to improve efficiency, advance technologies, and address systemic public health challenges. Full article

A major issue in industrial production is the generation of post-production wastes that are not biodegradable. The article presents an innovative solution for the management of industrial waste, which includes, among others, metal dust generated during the grinding of castings. The results of research on a concrete composite modified with metallic dust, a by-product from cast iron product manufacturing, were presented. The study analyzed the effect of using metallic dust as a partial replacement for fine aggregate at levels of 10%, 20%, 30%, 40%, and 50% on selected concrete properties. Tests included concrete mix consistency, compressive strength after 28 days and 6 months, density after 28 days of curing, bending strength, abrasion resistance using the Boehme disk method, durability in a salt chamber, and air content in hardened concrete. The research results indicate the possibility of using waste metal dust in concrete composites as a substitute for sand as a fine aggregate. An innovative waste processing solution allows the creation of a product with better abrasion resistance and compressive strength parameters while also having a good impact on the environment. Full article

Accurate prediction of settling velocities for irregular particles offers significant advantages in various fields, including more efficient water/wastewater treatment, environmental pollution control, industrial productivity, and sustainable resource utilization. These predictions are essential for advancing sustainable hydraulic engineering and environmental management. In this study, a new algorithmic modeling framework was proposed to estimate the terminal settling velocity of irregularly shaped particles/materials. The framework integrates advanced non-linear regression techniques with robust optimization methods. The model successfully incorporated seven key input parameters to construct a comprehensive mathematical representation of the settling process. The proposed explicit model demonstrates superior prediction accuracy compared to existing empirical and drag correlation models. The model’s validity was confirmed using a large and morphologically diverse dataset of 86 irregular materials and rigorously evaluated using an extensive battery of statistical goodness-of-fit parameters. The developed model is a robust and highly accurate tool for predicting the settling behavior of non-spherical particles in the transition flow regime. Beyond its technical merits, the model could offer significant sustainability benefits by enhancing the design and optimization of wastewater treatment systems. More precise predictions of non-spherical particle settling behavior could improve sedimentation or particle removal efficiency, potentially reducing energy consumption and mitigating adverse environmental impacts on industrial waste management and aquatic ecosystem preservation. Full article

Silver and gold nanoparticles (NPs) have gained considerable attention in recent years due to their wide-ranging applications in medicine, agriculture, industry, and other fields where they may interact with the environment. Green synthesis of NPs supports sustainability by reducing chemical waste and energy use while improving their biocompatibility through plant phytochemicals. Accordingly, it is important to assess the effects of metal NPs on microorganisms, which play vital roles in ecosystems and biogeochemical cycles. This study aimed to investigate microbial growth dynamics in the presence of green-synthesized silver and gold NPs (using an aqueous extract of Mentha × piperita leaves) and to evaluate potential mechanisms of their interaction. Microorganisms were cultivated in 96-well microtiter plates, and growth curves were analyzed alongside bacterial enumeration on Petri plates. Silver NPs affected the growth of Brevundimonas vesicularis USM1, Pseudarthrobacter oxydans USM2, and Pseudomonas putida USM4, although these strains exhibited partial resistance. In contrast, gold NPs did not inhibit the growth of the tested strains. The ability of Brevundimonas vesicularis USM1 to precipitate metal NPs highlights its potential for sustainable bioremediation applications. The findings contribute to a better understanding of the environmental impact and sustainability aspects of silver and gold NPs in microbial systems. Full article

The use of preservatives such as diuron and isoproturon in the paint industry is essential to protect products against microbial attack. However, these compounds are subject to strict regulation due to the harmful effects they have on the environment and human health. Therefore, analytical strategies to control the production process at paint plants are fundamental to ensure suitable products. In the present work, a low-cost portable square-wave voltammetry device with commercial screen-printed electrodes was proposed to control the starting products and to determine isoproturon and diuron levels in manufactured paint products. Under the optimized conditions (electrolyte HClO₄ 0.18 M, nickel oxide-doped carbon electrodes, E_SW = 0.02 V, E_step = 0.0015 V, and ƒ = 15 Hz), the results indicated satisfactory analytical performance, with detection limits of 3.5 and 3.0 mg L⁻¹ for isoproturon and diuron, respectively, and precision lower than 7.5% for both biocides. The analytical strategy employed to achieve satisfactory selectivity involved taking advantage of the specific interaction of cysteine with 1,2-benzisothiazol-3(2H)-one (BIT) as a potential interferent in some commercial products and the use of matrix match calibration. A recovery study provided values in the range of 92–104% for accuracy validation. A sample pretreatment step was needed due to the paint composition, and a miniaturized method was proposed here. The novelty of this method lies in the use of a portable voltammetry device in real-world industrial applications to control the paint production process using a cost-effective, time-saving, sustainable, and green protocol. The HEXAGON tool is used for assessing greenness and sustainability. The choice of reagents like HClO₄ and the minimization of waste from the small volumes used align with the principles of using safer solvents, a key concern in green and sustainable chemistry. Full article

Food loss and waste in school food services generate economic cost, environmental impacts, and social effects. Waste occurs in the final stages of the supply chain. It is particularly critical in educational institutions, leading to low nutrient intake during early stages of development and negatively impacting food security. Aiming to design a waste reduction strategy for the meal service of a preschool serving children aged 0–5 years, a descriptive observational study was conducted over a 6-month period. This study combined the measurement of the primary outcome (proportion of the served portion not consumed by food group) with the assessment of menu acceptability, the children’s food preferences, and the exploration of perceptions of both at-home caregivers and preschool professionals. Overall, the most frequent reasons for rejection were texture, preparation methods, and unfamiliarity with the food. The highest levels of waste were found in fruits and vegetables, with 17% left uneaten; protein-rich foods had a 15% waste rate, and cereals and tubers showed a 10% waste rate. Based on these findings, a family–school strategy is proposed that would increase household exposure to a wider variety of foods and establish periodic menu reviews to identify critical foods and ensure proper use in school food services. These results demonstrate that by enhancing food acceptance, we can decrease food waste, and in early stages, strengthen food security and nutritional use. Full article

The medicinal plants industry generates approximately 30 million tons of by-products annually, most of which remain underutilized. The common nettle (Urtica dioica L., Urticaceae) is a valuable medicinal plant, rich in polyphenols, vitamins, and essential fatty acids, widely used in food and pharmaceutical applications. Its by-products still lack sustainable valorization strategies. This study aimed to valorize nettle tea by-products and flowers using green extraction techniques and microbial biotransformation. Lyophilized aqueous/ethanolic extracts were fermented with Ligilactobacillus salivarius ATCC 11741 to assess whether fermentation could enhance the content and bioavailability of phenolic compounds while maintaining probiotic viability. The results showed that fermentation significantly increased phenolic content and antioxidant activity, with chlorogenic acid concentrations increasing up to 4-fold and caffeic acid derivatives up to 2.5-fold. L. salivarius remained viable during fermentation, demonstrating the potential for the production of added-value extracts and probiotic biomass. These findings indicate that nettle by-products can be efficiently converted into functional ingredients through low-energy, environmentally friendly processes, supporting sustainable production and waste valorization. Full article

Rice is a staple food for global nutrition, and its processing generates large volumes of waste with a consequent environmental impact. The industry needs to improve its capacity to manage and treat this waste with more sustainable options than traditional management methods, thereby mitigating the environmental impact of the rice industry. Among the waste streams generated, rice bran represents a significant fraction that is largely underutilized. This study proposes a comprehensive approach to rice bran recovery, aiming to transform 100% of the waste into bio-based products through a three-stage biorefinery approach that combines chemical and biological operations. The process began with the ethanolic extraction of rice bran, which yielded 20.58% (w·w⁻¹) rice bran oil. This oil, evaluated through both in vitro and in vivo trials, has demonstrated effectiveness when combined with commercial edible coatings, reducing post-harvest damage in grapes and lemons by 15–20%. Following extraction, the remaining defatted rice bran, accounting for 79.42% (w·w⁻¹) of the initial material, was used as a carbon-rich substrate for microbial fermentation by Haloferax mediterranei. This step converts 28.75% (w·w⁻¹) of rice bran into microbial biomass and 12.75% (w·w⁻¹) into polyhydroxybutyrate-valerate. The undigested residual biomass, comprising 37.95% (w·w⁻¹) of the starting material, was further valorized through the purification of high-value products such as cellulose (13.08% (w·w⁻¹)), hemicellulose (14.58% (w·w⁻¹)), and lignin (10.29% (w·w⁻¹)). Overall, the biorefinery model recovers 100% of the initial waste and demonstrates, under laboratory conditions, the model’s ability to transform rice bran into six products of industrial interest, offering an option with the potential to effectively manage rice bran waste and help circularize the production model of an industry that traditionally operates under a linear production model. Full article

Recycled aggregate sourced from construction and demolition waste presents a viable means of reducing the environmental impact associated with concrete production. However, previous research has shown that concrete incorporating recycled aggregate typically exhibits reduced strength and increased susceptibility to deterioration. In this work, eight concrete mixes were prepared using both virgin and locally sourced recycled coarse aggregate from the United Arab Emirates, with selected mixes incorporating various combinations of supplementary cementitious materials (SCMs) (ground granulated blast-furnace slag (GGBS) and silica fume). The mixes were tested over a period of 180 days to evaluate key mechanical properties, durability, and embodied carbon. It was found that partial replacement of Portland cement with GGBS and silica fume had no marked beneficial effect on the strength and water absorption of recycled aggregate concrete when compared to mixes containing virgin aggregate. However, improvements in resistance to chloride ingress and reductions in drying shrinkage were observed. Notably, the incorporation of SCMs resulted in a significant reduction in embodied carbon, with reductions in excess of 40% when compared with conventional Portland cement concrete. Full article

Heat exchangers are key components of advanced waste-heat recovery energy systems that operate on low-boiling working fluids. The efficiency and cost of power plants depend directly on their design characteristics. Increasing the heat-transfer surface area, on the one hand, reduces temperature differences and improves cycle efficiency, but on the other hand increases material consumption and equipment cost. For given fluid parameters and heat-exchanger duty, the required surface area is determined by the type of heat exchanger, the choice of device, the shape of the enhanced heating surface, and the methods of heat-transfer intensification. This paper provides a comprehensive analysis of the current state of heat exchangers for low-boiling working fluids and discusses their areas of application. A methodology has been developed for optimizing the main design characteristics of heat exchangers, including a search algorithm aimed at minimizing the total costs of equipment production and operation. Using this methodology, computational studies were carried out for advanced energy cycles with low-boiling working fluids (organic Rankine cycles, recompression supercritical CO₂ (s-CO₂) Brayton cycle). The relationships of weight, size, and cost parameters of heat exchangers for waste-heat recovery cycles using low-boiling fluids to exhaust-gas temperatures and external economic factors were obtained. Optimal channel geometric parameters and heat-exchanger design types were identified that ensure minimal material consumption and cost while delivering the required heat-transfer performance. Recommendations are formulated for selecting and designing heat exchangers for waste-heat recovery power plants using low-boiling working fluids, the implementation of which will improve their efficiency and reduce costs. Full article

Grain breakage serves as a primary causative factor for microbial infestation and oxidative deterioration, significantly diminishing product value and resulting in substantial grain waste and economic losses. The grain discharging process represents the most extensively involved and primary breakage-inducing stage throughout harvest handling and processing operations. However, impact and impact-induced breakage behavior during grain discharge are still poorly understood. To elucidate the impact-induced breakage behavior during grain discharge, this study first employed the discrete element method (DEM) to numerically simulate the discharging process, thereby quantifying the variation patterns of grain kinematic characteristics (e.g., velocity and attitude). Building upon the simulated kinematic data, a dedicated impact testing platform was constructed to investigate single-grain breakage. This enabled the determination of critical unit mass impact energy (along 90°: 106.4 J kg⁻¹; along 0°: 57.28 J kg⁻¹) and critical breakage velocity (along 90°: 14.59 m s⁻¹; along 0°: 10.70 m s⁻¹) under two extreme impact attitude conditions. By integrating the DEM-derived kinematics with the experimentally obtained breakage thresholds, a breakage probability zoning diagram for both large-scale and small-scale discharge processes was developed. Finally, leveraging this comprehensive understanding of the flow and breakage mechanics, theoretical models were successfully established to predict key engineering design parameters, including mass flow rate, impact force, and impact pressure. All models were validated and demonstrated excellent predictive capabilities. The research result is of guiding significance for the design of relevant parameters of discharge systems to minimize grain breakage loss to the greatest extent possible. Full article

Achieving long-term stable optimization in complex industrial processes (CIPs) is notoriously challenging due to their unclear physical/chemical reaction mechanisms, fluctuating operating conditions, and stringent regulatory constraints. A significant gap persists between promising artificial intelligence (AI) algorithms developed in academic research and their practical deployment in industrial actual processes. To bridge this gap, this article introduces the AI- and security-empowered end–edge–cloud modular platform (AISE³CMP). It consists of four systems such as whole-process AI modeling, end-side basic loop and AI-assisted decision-making, edge-side security isolation and AI control, and cloud-side security transmission and AI optimization. The data isolation collection module of the platform was deployed at a municipal solid waste incineration (MSWI) power plant in Beijing, where it collected multimodal data from real-world industrial sites. The platform’s functionality and effectiveness were validated through the software and hardware developed at the Smart Environmental Protection Beijing Laboratory. The experimental results show efficient and reliable signal transmission between the systems, confirming the platform’s ability to meet the computational demands of AI-based optimization and control algorithms. Compared to previous platforms, AISE³CMP features a dual-security transmission mechanism to mitigate data exchange risks and a modular design to enhance integration efficiency. To the best of our knowledge, this platform is the first prototype of a portable, end-to-end cloud platform with a dual-layer security mechanism for CIPs. While the platform effectively addresses data transmission security, further strengthening of cloud-side data protection and ensuring operational safety on the end-side remain significant challenges for the future. Additionally, utilizing this architecture to enable multi-region and multi-plant data sharing, in order to develop industry-specific large language models, represents a key research direction. Full article

This research study addresses the critical contradiction within global food systems: unsustainable consumption patterns and persistent food insecurity coexist and are exacerbated by food waste, which deepens socioeconomic inequalities and generates negative environmental externalities. In this scenario, higher education plays a central role in adopting comprehensive strategic frameworks to develop specialized human capital and influence society. This study analyzes a Service Learning model that integrates the CFS-IRA Principles to promote the SDGs and ensure responsible consumption. Based on a case study of the Food Bank Chair spanning 10 years and 212 projects, the implementation of this model was evaluated using the Working with People (WWP) method, which combines the development of postgraduate students’ skills with community service to address social problems. The results demonstrated the effectiveness of the SL-WWP model in strengthening students’ technical, social, and ethical competencies while reducing food waste. The evaluation showed strong alignment with key SDGs, with outstanding performance in governance, although the need to strengthen environmental and social criteria was identified. The originality lies in integrating the CFS-IRA Principles into an SL model that encourages innovative cooperation among universities, civil society, and public–private sectors, offering a replicable proposal for higher education institutions to establish themselves as agents of change towards sustainability. Full article

This study employs a practice-oriented research method, emphasizing practical application rather than laboratory testing, and was conducted in Pingtung County, Taiwan, from 2017 to 2023. The practical results of the five case studies demonstrate that (1) eco-friendly buildings integrating agricultural and fishery waste overcome the obstacles of obtaining building permits and (2) the carbon emissions of exterior walls made of pozzolana are only 44% of those of reinforced concrete. This study contributes to understanding the contemporary characteristics of sustainable buildings and provides directly applicable insights into and suggestions on how buildings can actively utilize local materials. Full article