Search Results (420)

By the time of this study, Kiteezi landfill was Uganda’s largest waste disposal site and received substantial volumes of municipal solid waste. In the present study, water (n = 36), leachates (n = 36), superficial sediments (n = 30), and Colocasia esculenta corms (n = 6) were sampled from Kiteezi landfill in the dry and wet seasons of 2022 before its tragic collapse in 2024. The physicochemical parameters (pH, electrical conductivity, temperature, and oxidation–reduction potential) and concentration of potentially toxic elements (As, Cu, Cr, Pb, and Zn) were analyzed using standard methods and inductively coupled plasma-optical emission spectrometry, respectively. Significant seasonal variations (p < 0.05) were observed for all the physicochemical parameters of water and leachates except temperature. Further, significantly higher concentrations (p < 0.05) of potentially toxic elements (PTXEs) were quantified in environmental matrices sampled during the dry season than the wet season. Arsenic and Pb concentrations in water surpassed their WHO permissible limit of 0.01 mg/L. The concentrations of PTXEs were higher in downstream samples (p < 0.05), indicating that landfill activities led to their enrichment in matrices near the facility. Ecological and pollution risk indices indicated that there is severe enrichment of Cu and Zn in the sediments, with dry season downstream samples having contamination factors and geoaccumulation indices of 539.3 and 74.7 and 8.5 and 5.6, respectively. Although ingestion of water may not cause probable health risks, consumption of Colocasia esculenta corms could lead to non-carcinogenic and cancer health risks in both children and adults (hazard indices = 0.085–189.0 and total cancer risk values of 7.33 × 10⁻⁶–4.87 × 10⁻³). These results emphasize the need that any new replacement for Kiteezi landfill should be properly planned and managed to mitigate potential environmental pollution with xenobiotics. Full article

Maternal healthcare guidelines (MHCGs) are documents with detailed information on how to manage maternal and perinatal conditions step by step and accordingly to reduce preventable maternal and perinatal deaths. The National Maternity Guidelines Committee in the Department of Health, guided by the WHO, developed the (MHCGs) to ensure that every primary healthcare facility (PHC) has one or two midwives at their disposal to use, but its implementation remains a huge problem in South Africa. The purpose of this study is to evaluate the knowledge, practices, and attitudes of midwives during the implementation of MHCGs in a selected district, Limpopo province, South Africa. A quantitative methodology will be employed; cross-sectional descriptive research design will be used. The population of this research study will be midwives working in the PHCs of a selected district, Limpopo province, South Africa. The convenient sampling approach will be used; whereby self-developed semi-structured questionnaires will be used as a data collection instrument. The collected data will be analyzed using the Statistical Package for Social Sciences (SPSS), version 29, with the help of a statistician. The results will be available after data collection. The conclusion and recommendations will be based on the findings of the study. Full article

Sewage sludge, as a by-product of wastewater treatment, represents a significant cost factor in the operation of wastewater treatment plants and accounts for up to 50% of total costs. As sewage sludge still contains a high proportion of water after the basic treatment processes (thickening, stabilization and dewatering), sludge drying helps to reduce further treatment and disposal costs. Conventional drying methods are associated with high energy consumption, making solar drying a more cost-effective alternative. This paper analyzes the economic aspects of constructing a sewage sludge solar drying facility with the help of an expert system based on neural networks. The system considers a range of parameters (plant capacity, transport distance, transport and treatment costs, etc.) to assess the values of the investment as well as the operation and maintenance costs. The analysis was carried out using NeuralTools (Lumivero). Two main options for sludge disposal were investigated: treatment at a regional center (with the sub-options of own or outsourced transport) and handing over of sludge to another legal entity. In total, five neural network models were developed based on the input load (from 75 to 10,000 t/year and from 10,000 to 20,000 t/year) and transport method (own or outsourced transport), resulting in an analysis of over 670,000 scenarios. The key output variable was the net present value of costs over a 30-year period. The results demonstrated high model accuracy (error < 5%) and allowed a comparison of the profitability of constructing a sewage sludge solar drying facility with alternative methods of sludge disposal, in particular with the transport and disposal of the dewatered sludge. Full article

In the context of global sustainable development, the construction of green mining facilities has emerged as a pivotal strategy for advancing sustainable mining practices. As a substantial mineral resource base in China, the Qinghai-Xizang Plateau (QXP) is of significant concern due to its importance for mineral exploitation. However, the natural conditions of the region, such as freezing temperatures, low oxygen levels, frequent freeze–thaw cycles, and fragile ecology, pose substantial challenges to mining activities, making green mine construction an inevitable choice for mining development on the QXP. This study uses SWOT analysis to macroscopically evaluate the strengths, weaknesses, opportunities, and threats of green mine construction on the QXP. This study adopts SWOT analysis to sort out, from a macro and systematic perspective, the internal resource endowments, technical reserves, external policy and market opportunities, as well as multiple challenges such as ecological vulnerability, harsh climate, regulation, and public opinion in the construction of green mining on the QXP. Furthermore, four typical cases, namely the Julong Copper Mine, Zhaxikang Lead–Zinc Mine, Zaozigou Gold Mine, and Duolong Copper Mine, are selected for analysis, and their differentiated paths in ecological restoration, digital mines, tailings disposal, and community-benefit sharing are summarized. International comparisons reveal the similarities and differences in policies, technologies, and other aspects between the QXP and other high-altitude regions. The study holds that it is necessary to promote the coordinated development of resource exploitation and ecological protection in green mining on the QXP through technological innovation, policy optimization, community collaboration, and the construction of a full-life-cycle environmental-monitoring system. At the same time, it points out the limitations of the current research in quantitative analysis and future research directions. Full article

The exponential increase in global solid waste generation poses significant environmental, economic, and social challenges, particularly in rapidly urbanizing regions. Traditional waste management methods that focus on handling and disposal have proven unsustainable because of their negative impacts on air, soil, and water quality, and their contribution to greenhouse gas emissions. In response, the concept of zero-waste cities, rooted in circular economy principles, has gained increasing attention in recent years. This study proposes a comprehensive and integrated waste management system designed to optimize resource recovery across four distinct waste streams: household, healthcare, green/organic, and inert. The system integrates four specialized facilities: a Secondary Sorting Facility, Energy Recovery Facility, Composting Facility, and Inert Processing Facility, coordinated through a central Primary Sorting Hub. By enabling interconnectivity between these processing units, the system facilitates material cascading, maximizes the reuse and recycling of secondary raw materials, and supports energy recovery and circular nutrient flow. The anticipated benefits include enhanced operational efficiency, reduced environmental degradation, and generation of multiple revenue streams. However, the implementation of such a system faces challenges related to high capital investment, technological complexity, regulatory fragmentation, and low public acceptance. Overcoming these limitations will require strategic planning, stakeholder engagement, and adaptive governance. Full article

Wastewater treatment plants (WWTPs) are critical infrastructure that lessen the environmental impacts of human activity by stabilizing wastewaters laden with organics, chemicals, and nutrients. WWTPs face an increasing global population, greater wastewater volumes, stricter environmental regulations, and additional societal pressures to implement more sustainable and energy-efficient waste management strategies. WWTPs are energy-intensive facilities that generate significant GHG emissions and involve high operational costs. Therefore, improving the process efficiency can lead to widespread environmental and economic benefits. One promising approach is to integrate anaerobic digestion (AD) with hydrothermal carbonization (HTC) to enhance sludge treatment, optimize energy recovery, create valuable bio-based materials, and minimize sludge disposal. This study employs an LCA to evaluate the environmental impact of coupling HTC with AD compared to conventional AD treatment. HTC degrades wastewater sludge in an aqueous medium, producing carbon-dense hydrochar while reducing sludge volumes. HTC also generates an aqueous byproduct containing >30% of the original carbon as simple organics. In this system model, the aqueous byproduct is returned to AD to generate additional biogas, which then provides heat and power for the WWTP and HTC process. The results indicate that the integrated AD + HTC system significantly reduces environmental emissions and sludge volumes, increases net energy recovery, and improves wastewater sludge valorization compared to conventional AD. This research highlights the potential of AD + HTC as a key circular bioeconomy strategy, offering an innovative and efficient solution for advancing the sustainability of WWTPs. Full article

The rapid growth of electric vehicles (EVs) in the Jakarta Greater Area is expected to significantly increase the volume of end-of-life (EoL) batteries, necessitating an efficient and sustainable waste management system. This study designs a reverse logistics network that includes Collection Centers (CCs), a combined Remanufacturing and Recycling Center (RMC), and a Waste Disposal Center (WDC). Dealer clusters are identified using K-means clustering to determine the optimal CC locations. A deterministic mixed-integer linear programming (MILP) model is developed to minimize total costs. It comprises acquisition, transportation, processing, facility, and carbon tax components. The model yields a minimum total cost of IDR 1,236,435,000,187, with processing costs contributing the largest share (56.68%), followed by transportation (29.30%). The selected facilities include five CCs (CCA-1, CCE-2, CCK-3, CCM-4, and CCR-5), one RMC (RMC-1), and one WDC (WDC-1). Based on battery health, the batteries are classified into three categories: L1 (>80% health, suitable for remanufacturing), L2 (60–80%, suitable for recycling), and L3 (<60%, directed to disposal). L1 and L2 batteries are directed to RMC-1, while L3 batteries and solid waste are routed to WDC-1, totaling 1.029 tons. The results emphasize the need for improving processing efficiency and strategic facility placement to enhance the sustainability and cost-effectiveness of EoL battery management in urban EV ecosystems. Full article

This paper presents the results of a survey of the designed biological wastewater treatment facilities of an enterprise specializing in the production of rubber products. The aim of the study was to assess the efficiency of wastewater treatment systems under the conditions of a salvo discharge of industrial effluents that differ in composition from domestic wastewater. The analysis covered the parameters of water supply, water disposal, and wastewater characteristics at various stages of treatment. Three samples were taken: after washing the premises (WW1), at the inlet to the treatment facility (WW2), and at the outlet after treatment (WW3). Experimental assessment of the purification efficiency for key pollutants showed a high degree of removal of surfactants (91.2%), oil products (84.4%), and COD (63.4%). However, phosphorus–phosphate turned out to be significantly higher than the norm—2.32 mg/L with an acceptable level of 0.2 mg/L—which corresponds to an excess of 11.6 times. A low degree of ammonium nitrogen removal was also revealed—62%. Calculations showed a critically high ratio of COD/BOD5 = 5.1 with the recommended <2.6, which indicates a small share of biodegradable substances and the need to implement physical and chemical treatment methods. The absence of the characteristic smell of household wastewater and the presence of black inorganic sediment confirm the toxicity of emerging pollutants for activated sludge. It is concluded that the installed biological treatment system cannot cope with the salvo loads of industrial wastewater. Optimization measures are proposed: preliminary local treatment, dosed feed, and a separate treatment system. Full article

With the global economic restructuring and the consequent population mobility, urban shrinkage has become a common phenomenon. The Qinling–Daba Mountains, a zone with a key ecological function in China, have long experienced population decline and functional degradation. Clarifying the dynamics and influencing factors of urban shrinkage plays a vital role in supporting the sustainable development of the region. This study, using permanent resident population growth rates and nighttime light data, classified cities in the region into four spatial patterns: expansion–growth, intensive growth, expansion–shrinkage, and intensive shrinkage. It further examined the spatial characteristics of shrinkage across four periods (2005–2010, 2010–2015, 2015–2020, and 2020–2022). A Geographically and Temporally Weighted Regression (GTWR) model was applied to examine core influencing factors and their spatiotemporal heterogeneity. The results indicated the following: (1) The dominant pattern of urban shrinkage in the Qinling–Daba Mountains shifted from expansion–growth to expansion–shrinkage, highlighting the paradox of population decline alongside continued spatial expansion. (2) Three critical indicators significantly influenced urban shrinkage: the number of students enrolled in general secondary schools (X₅), the per capita disposable income of urban residents (X₇), and the number of commercial and residential service facilities (X₁₂), with their effects exhibiting significant spatiotemporal heterogeneity. Temporally, X₁₂ was the most influential factor in 2005 and 2010, while in 2015, 2020, and 2022, X₅ and X₇ became the dominant factors. Spatially, X₇ significantly affected both eastern and western areas; X₅’s influence was most pronounced in the west; and X₁₂ had the greatest impact in the east. This study explored the patterns and underlying drivers of urban shrinkage in underdeveloped areas, aiming to inform sustainable development practices in regions facing comparable challenges. Full article

Multi-objective evolutionary algorithms (MOEAs) have emerged as powerful optimization tools for addressing the complex, often conflicting goals present in modern waste disposal systems. This review explores recent advances and practical applications of MOEAs in key areas, including waste collection routing, waste-to-energy (WTE) systems, and facility location and allocation. Real-world case studies from cities like Braga, Lisbon, Uppsala, and Cyprus demonstrate how MOEAs can enhance operational efficiency, boost energy recovery, and reduce environmental impacts. While these algorithms offer significant advantages, challenges remain in computational complexity, adapting to dynamic environments, and integrating with emerging technologies. Future research directions highlight the potential of combining MOEAs with machine learning and real-time data to create more flexible and responsive waste management strategies. By leveraging these advancements, MOEAs can play a pivotal role in developing sustainable, efficient, and adaptive waste disposal systems capable of meeting the growing demands of urbanization and stricter environmental regulations. Full article

This work studies and analyzes the transition from a linear to a circular economy through wastewater treatment and resource recovery. As wastewater volumes grow, sustainable management becomes critical. This study highlights the reuse of treated effluent, beneficial sludge utilization, and energy generation via anaerobic digestion. Wastewater treatment plants should be envisioned as hubs for recovering water, materials, and energy, rather than disposal facilities. Emphasizing resource efficiency, the circular economy approach offers viable solutions to challenges related to resource scarcity, climate change, and ecological impact. Full article

Currently, natural resources are rapidly depleting as a result of increasing construction facilities. Increasing energy consumption with increasing construction is another serious issue. In addition, many problems that threaten the environment and human health arise during the disposal and storage of waste materials obtained in different sectors. The main objective of this study is to investigate the substitution of cotton (CW), chicken feather (CFF) and stone wool waste (SWW) from pumice aggregate in the production of environmentally friendly hollow blocks. To achieve this, CW, CFF and SWW were substituted for pumice at ratios of 2.5–5–7.5–10% in mass, and hollow blocks were produced with this mixture under low pressure and vibrations in a production factory. Various characterization methods, including a size and tolerance analysis, unit volume weight test, thermal conductivity test, durability test, water absorption test and strength tests, were carried out on the samples produced. This study showed that waste fibers of chicken feather and stone wool are suitable for the production of sustainable and environmentally friendly hollow blocks that can reduce the dead load of the building, have sufficient strength, provide energy efficiency due to low thermal conductivity and have a high durability due to a low water absorption value. Full article

Due to increasing environmental concerns and the constant development of the bottling industry, research into the environmental impact of beverage packaging processes is crucial. The aim of this article is to determine the environmental impact, in selected aspects, of automated beverage bottling and packaging processes using life cycle analysis (LCA). The analysis covers key process stages, such as filling, packaging and internal transport, in the context of raw material consumption, but also energy and waste generation. This work focuses primarily on the impact of changing the raw material used for bottle and shrink film production on the environmental impact of the studied technical facility within the adopted system boundaries and on analyzing scenarios for the management of these post-consumer materials. This research has shown that the stage associated with the greatest negative environmental impact is the shrinking of the film around the bottles. Furthermore, it has been demonstrated that recycling plastic film and bottle waste is a more environmentally friendly solution than landfill disposal. The analysis shows that using recycled materials in the tested production line allows for the reduction of harmful emissions and a reduction in the overall environmental footprint of the tested system. Full article

The co-disposal of municipal solid waste incineration fly ash (MSWI-FA) in cement kilns is an effective method for managing incineration by-products in China. However, the presence of heavy metals in MSWI-FA raises environmental concerns. This study analyzed the Cu, Zn, Cd, Pb, Cr, and Ni concentrations in MSWI-FA from 11 representative facilities across China and assessed the efficacy of a three-stage water washing process for Cl and heavy metal removal. The results revealed significant regional variations in heavy metal content that were strongly correlated with surface soil levels, with Zn, Pb, and Cu exhibiting the highest concentrations. Elemental correlations, such as Cu-Pb and Zn-Cd synergies and Cd-Ni antagonism, suggest common waste sources and temperature-dependent volatilization during incineration. The washing process (solid–liquid ratio = 1:10) achieved 97.1 ± 2.0% Cl removal, reducing residual Cl to 0.45 ± 0.32%, but demonstrated limited heavy metal elimination (10.28–19.38% efficiency), resulting in elevated concentrations (32.5–60.8% increase) due to 43.4 ± 9.2% mass loss. Notably, the washing effluents exceeded municipal wastewater discharge limits by up to 52-fold for Pb and 38-fold for Cd, underscoring the need for advanced effluent treatment. To mitigate environmental risks, the addition of washed MSWI-FA in cement kilns should be restricted to ≤0.5%, with Cd content prioritized in pre-disposal assessments. This study provides actionable insights for optimizing MSWI-FA co-processing while ensuring compliance with ecological safety standards. Full article

In recent decades, the River Ganges in India has been heavily contaminated with domestic waste and industrial toxins because of cultural activities, a lack of community awareness, an absence of sewage disposal facilities, and rapid population growth. Previous studies have focused separately on either the physical or social factors associated with River Ganges pollution but have not combined these elements in a single study. To fill this research gap, our study assesses the bio-physical and social vulnerability of the River Ganges by using a holistic approach. The following four sampling stations were selected: Rishikesh, Haridwar, Kanpur, and Varanasi. These locations were chosen to test the water quality in bio-physical aspects and to assess the social perceptions of river vulnerability among the residents and visitors. Perceptions of river water quality and likely sources of pollution were gathered via the distribution of over 1000 questionnaires. Data collection took place in the winter and summer of 2022 and 2023. The results showed that river water quality is not suitable for drinking purposes at any of the four cities without conventional treatment, and that the river is unsuitable for bathing at all locations, except upstream of Rishikesh. Nearly 50% of those questioned agreed that the river is polluted, whilst 74% agreed that pollution has increased in recent decades, particularly in the last 10 years. These compelling results are critical for policymakers and decision makers. They highlight the urgent need for novel strategies that address Ganges pollution while fostering community health education and environmental management. By dispelling myths surrounding river quality, this study strengthens the ongoing efforts to restore the Ganges, ensuring that it remains a vital lifeline for present and future generations. Full article