Search Results (348)

Accurate methane emission estimates are essential for climate policy, yet current field methods often struggle with spatial constraints and source complexity. Ground-based mobile approaches frequently miss key plume features, introducing bias and uncertainty in emission rate estimates. This study addresses these limitations by using small unmanned aerial systems equipped with precision gas sensors to measure methane alongside co-released tracers. We tested whether arc-shaped flight paths and alternative ratio estimation methods could improve the accuracy of tracer-based emission quantification under real-world constraints. Controlled releases using ethane and nitrous oxide tracers showed that (1) arc flights provided stronger plume capture and higher correlation between methane and tracer concentrations than traditional flight paths; (2) the cumulative sum method yielded the lowest relative error (as low as 3.3%) under ideal mixing conditions; and (3) the arc flight pattern yielded the lowest relative error and uncertainty across all experimental configurations, demonstrating its robustness for quantifying methane emissions from downwind plume measurements. These findings demonstrate a practical and scalable approach to reducing uncertainty in methane quantification. The method is well-suited for challenging environments and lays the groundwork for future applications at the facility scale. Full article

Microbiological safety and quality consistency are critical challenges in the production of traditional Indian fried snacks, particularly in small-scale food enterprises. With growing export demand, maintaining strict quality control measures is essential. This study assessed the microbiological and physicochemical quality of five traditional Indian fried snacks—Kerala Murukku, Kerala Mixture, Banana Chips, Tapioca Chips, and Achappam—produced in a Food Safety Management System (FSMS)-certified facility over a four-year period (2020–2023). Products were evaluated for moisture, pH, salt content, acid value, and Total Plate Count (TPC). The number of ingredients for each product was recorded from standardized product formulation documents. TPC levels remained within acceptable limits (below 50,000 CFU/g) across all products. Among them, Kerala Mixture consistently showed the highest microbial counts (up to 4.61 log CFU/g) and Achappam the lowest, with no detectable variance (1.00 log CFU/g). Statistically significant year-wise differences (p < 0.05) were observed in all quality parameters. Kerala Mixture showed variation in salt and microbial load; Kerala Murukku varied in moisture, pH, and salt; while Tapioca Chips varied in moisture and salt. PCA identified that TPC, salt content, number of ingredients, and pH were key contributors to product variability. Cluster analysis confirmed Kerala Mixture as the most susceptible product to contamination risk. These findings provide valuable insights into the quality trends within an FSMS-certified environment and highlight the importance of strict post-processing controls. Full article

This work introduces a new type of water evaporation-driven nanogenerator (S-WEG) utilizing the natural mineral sepiolite, which capitalizes on its hierarchical nanoporous architecture and intrinsic hydrophilicity to harvest energy from ambient humidity through capillary-driven evaporation. The S-WEG, fabricated via a facile drop-coating drying method, demonstrates remarkable mechanical flexibility and sustained operational reliability. Our results demonstrate that by optimizing evaporation height and width, the S-WEG can generate a short-circuit current of ~0.6 μA and an open-circuit voltage of ~0.9 V. Through series and parallel configurations of multiple S-WEG units, the current and voltage outputs can be effectively amplified to power small-scale electronics. Full article

An integrated approach is sorely needed to treat biogas emanating from anaerobic digesters (AD) which is cost-effective, in terms of upgrade/purification to ~95–98% methane needed for pipeline injection. This is a very pressing environmental and waste-management problem. At present, biogas water-/solvent-washing operations require significant capital investment, with high operational and maintenance costs. In the present study, we deployed a facile and efficient novel nanobubble-formation approach using applied electric fields to boost biogas-enrichment operations: we achieve substantial methane enrichment via selective CO₂ and H₂S take-up in water in the form of nanobubbles. This enables an integrated waste-processing vision using cutting-edge engineering-science advances, and making anaerobic digestion a circular-economic and practical reality, that can be deployed at scale—initially developing at the small scale—and points the way for low-energy CO₂ capture in the form of nanobubbles by dint of the electric-field approach. In addition, we carried out nanobubble generation using various gases for water treatment for both up- and down-stream sludge-containing (waste)water, achieving meaningful operational successes in AD operations and organic-fertiliser production, respectively. Full article

Nowadays, treating residual brine from desalination systems is an important issue for sustainable water management, where Mechanical Vapour Compression (MVC) systems are a great energy-efficient option for small-scale desalination plants. In this paper, an MVC model with TRNSYS 18 software is proposed, validated using real data from an MVC experimental system. A relevant contribution of this paper is that each component of the MVC system is individually modelled considering the challenges faced in the real experimental facility and only using input variables that are managed by real MVC plant operators, achieving accurate output results with the proposed model. Assessment of the model uses real datasets from a real MVC experimental facility in Spain, with more than 30,000 individual real values during validation. As a result, the model generated more than 350,000 values each day used for validation purposes. Comparing output variables, such as distillate production and final salinity, the accuracy of the model achieves a mean absolute error of 6.87% and relative errors lower than $2.90\%$. This contribution highlights the importance of using accurate simulation tools, providing valuable information to optimize MVC systems. Full article

Exploring the cognitive and affective image dimensions involved in the formation of attractive sports destinations is essential to understand how sports activities influence participants’ experiences. This study explores how municipal sports programs and small-scale events shape both the cognitive and affective image of a destination. The research was conducted among 456 adult participants engaged in public sports events and recreation programs in various municipalities across Attica, Greece. Participation was voluntary and based on an open public call. The questionnaire was adapted from (a) scale, which examines the influence of a sports event image on a destination image—it included 17 items measuring the cognitive image destination grouped into four factors: (1) environment, (2) experiences, (3) attractions, and (4) entertainment–infrastructure, as well as 5 items assessing one factor of affective image destination—and (b) a scale for the intention to participate in sports events and exercise programs. The findings provide insights into how community-level sports initiatives contribute to form a favorable destination image, not only through tangible elements like facilities and environment but also through emotional engagement and social connectivity. These results can inform the development of more targeted and impactful local sports programs that enhance participant’s satisfaction and foster long-term community involvement. Full article

Against the backdrop of China’s “dual carbon” strategy, investigating the carbon emission characteristics and low-carbon operational status of wastewater treatment plants (WWTPs) across regions is pivotal for achieving synergistic pollution reduction and carbon mitigation. Leveraging 2024 operational data from 98 WWTPs in eastern China—encompassing treatment volume, energy consumption, sludge production, and chemical dosages—this study refined the Assessment Standard for Carbon Mitigation in Municipal WWTPs and Technical Specification for Low-Carbon Operation of WWTPs. A novel carbon accounting framework and low-carbon performance evaluation system were subsequently developed to analyze the impacts of treatment scale, technological configuration, and load rate on carbon footprints. Key findings revealed an average carbon intensity of 0.399 kg CO₂-eq/m³ for the region, with small-scale facilities (0.582 kg CO₂-eq/m³) exhibiting significantly higher emissions compared to their large-scale counterparts (0.392 kg CO₂-eq/m³). Indirect emissions constituted 62.1% of the total footprint, while chemical dosing contributed 14.2%, primarily driven by carbon sources and phosphorus removal agents. Fossil-derived CO₂ accounted for 4.6% of emissions. Notably, the AAO process demonstrated the lowest carbon intensity (0.370 kg CO₂-eq/m³), whereas SBR systems registered the highest (0.617 kg CO₂-eq/m³). Furthermore, 25% of the assessed facilities were classified as high-emission plants. Strategic recommendations are proposed, including prioritizing AAO process optimization, implementing intelligent chemical dosing control, utilizing food wastewater as an alternative carbon source, and enhancing operational load rates, to advance synergistic environmental and carbon mitigation goals in eastern China’s wastewater sector. Full article

Small-scale decentralised wastewater treatment facilities are essential to provide services to remote regional communities. This study presents an innovative and sustainable approach to wastewater treatment by integrating ozone nanobubble technology (ONBT) with constructed floating wetlands (CFWs). Effluent from a community wastewater treatment plant was used in two sets of twelve 170-litre tanks, each with different ONBT–CFW treatment combinations, and monitored for key water quality parameters over an eleven-week study. The experiment results indicated that the combined ONBT–CFW system, particularly with higher ozone doses, achieved substantial reductions in total nitrogen (>70%), BOD (>43%), and E. coli (100%). ONBT alone showed limited effectiveness on nutrient removal, while CFWs performed well in reducing nutrients and controlling E. coli. However, phosphorus removal was modest (~12%), suggesting the need for complementary strategies. Overall, the hybrid ONBT–CFW system demonstrated superior performance compared to individual treatments, offering strong potential for improving wastewater quality and treatment. Full article

This study describes the step-by-step development of a simplified system which can be implemented in industrial facilities with the help of their own surplus of plastic waste, mainly packaging waste, to reach a level of energy autonomy or semi-autonomy. This waste is converted to about 57,500 L of synthetic pyrolysis oil, which can then be used to power industries, being fed into a Combined Heat and Power system. To achieve this goal, the design has hydrocarbon stability at elevated temperature and restricted oxygen exposure, so that they can be converted to new products. Pyrolysis is a key process which causes thermo-chemical changes—ignition and vaporization. The research outlines the complete process of creating a basic small-scale pyrolysis system which industrial facilities can use to generate energy from their plastic waste. The proposed unit processes 360 tons of plastic waste yearly to produce 160 tons of synthetic pyrolysis oil which enables the generation of 500 MWh of electricity and 60 MWh of heat. The total investment cost is estimated at EUR 41,000, with potential annual revenue of up to EUR 45,000 via net metering. The conceptual design proves both environmental and economic viability by providing a workable method for decentralized waste-to-energy solutions for Small and Medium-sized Enterprises. Full article

Maritime trade in Bangladesh is growing significantly, as observed by UNCTAD, which reported 3.20 mTEUs throughput in 2022. Additionally, the principal seaport, Chattogram Port, reported a port throughput of 3.27 mTEUs in 2024, the historical record for any port in Bangladesh. More than 50% of imports and exports, including empty containers, were handled in 2024 through 19 nos close dry ports in Chattogram City by applying small-scale intermodal systems, where the performance of pure intermodal from/to mid-range dry ports (3 Nos) to Chattogram Port is 2.53%. By 2030, the government wants all import and export operations to be conducted through dry ports. Furthermore, the current volume of international goods freight cannot be handled by the dry ports that are currently in place. This research applied mixed methods to explore the opportunities to set more dry ports and the application of intermodal systems for increasing the seaport’s efficiency, productivity, and competitiveness. The Focus Group Discussion (FGD) method was used to know the dry port location, investment, and policy in creating the opportunity to set up more dry ports in Bangladesh. In the findings, 82.50% of participants agreed that existing facilities are not enough and need to establish more dry ports to handle current and future volumes of containers. Moreover, the responses reveal a division of opinion on establishing a dry port outside of Chattogram, with a notable inclination towards opposition. According to 62% of respondents, dry ports outside Chattogram are necessary. To enhance intermodal connectivity and facilitate easier cargo transfers between ports and hinterland regions, integrated infrastructure development would be in line with national economic objectives. The research aims to investigate the possibilities for establishing additional dry ports across the country to boost seaport productivity, efficiency, and competitiveness by utilizing intermodal freight transportation systems to cut costs and time while also considering environmental factors like CO₂ emissions. Full article

This study investigates membrane fouling control in a submerged anaerobic ceramic membrane bioreactor (AnCMBR) treating high-strength food wastewater (chemical oxygen demand (COD): 10–30 g/L). A hybrid strategy combining mechanical cleaning via a moving rubber blade (MRB) (termed anaerobic ceramic blade MBR (AnCBMBR)) with intermittent salt-assisted backwash (SAB) was tested to manage transmembrane pressure (TMP) and sustain treatment performance. During more than 300 days of field operation, MRB alone maintained stable TMP below 0.15 kg_f/cm² without backwashing, achieving more than 90% COD removal at a very short hydraulic retention time (HRT) of 1–2 days. Introducing intermittent SAB further stabilized operations and enhanced total phosphorus (T-P) removal by facilitating struvite formation through the interaction of MgCl₂ and phosphorus in the reactor. The AnCBMBR system demonstrated reliable, long-term fouling control and treatment efficiency, even under high organic loads, proving its viability for small-scale facilities managing concentrated food wastewater. This study advances practical strategies for sustainable anaerobic MBR operation under challenging industrial conditions. Full article

Malting is one of the most energy-intensive stages in beer brewing, yet its environmental impacts remain under-characterized despite recent efficiency gains. Barley and malt transport drive significant greenhouse gas emissions in import-dependent countries, while local, small-scale production can offset those savings through lower process efficiencies or higher resource use. This study conducted a cradle-to-gate Life Cycle Assessment (LCA) of three Italian malthouses—small, medium, and large—using SimaPro 10.2.0.0 and a functional unit of 1 kg of malted barley delivered by bulk truck to local breweries. Primary data on barley, water, methane, and electricity consumption, as well as waste generation, were collected via questionnaires; secondary data were sourced from Ecoinvent and Agri-Footprint. Impact categories were evaluated using the Cumulative Energy Demand (CED) and Product Environmental Footprint (PEF) methodologies. Barley cultivation dominates the footprint (84–92% of total impacts when using local grain). Drying and transport contribute 3.7–4.4% and 0–8.4% of impacts, respectively, depending on facility scale and import share. Smaller malthouses exhibit higher per-kilogram impacts due to lower energy efficiency and transportation modes. Mitigation strategies —including sustainable agriculture, renewable energy adoption, logistics optimization, and process improvements—can substantially reduce impacts. Notably, sourcing barley from low-impact suppliers alone lowers the carbon footprint from 0.80 to 0.66 kg CO_2e/kg, freshwater eutrophication from 227 to 32 CTU_e/kg, land use from 196 to 136 Pt/kg, and overall PEF from 192 to 81 µPt/kg. These results underscore the critical role of feedstock sourcing and process efficiency in decarbonizing malt production and provide a quantitative baseline for targeted sustainability interventions. Full article

Mountainous cities are especially vulnerable to flooding and water quality degradation due to surrounding steep terrain, variable precipitation, and fragile ecosystems. Existing studies often rely on small-scale scenario simulations or computationally intensive optimization algorithms, limiting their practical application. This study proposes a spatial layout strategy for stormwater management tailored to mountainous environments, using the Xining sponge city pilot area as a case study. Based on the “source–sink” theory, flood risk was assessed at the district scale, and the Storm Water Management Model (SWMM) was applied to evaluate four Low-Impact Development (LID) deployment schemes. A novel indicator—the source–sink coupling optimization degree (SSCOD)—was introduced to quantify LID spatial coordination between source and sink zones and identify optimal configuration thresholds. Results show that the four LID allocations significantly reduce runoff and improve water quality compared to the no-LID baseline. Analyses also reveal diminishing returns: optimal LID performance occurs when SSCOD ranges from 0.345 to 0.423, with 24.24–24.41% of LID facilities placed in high-risk zones. Beyond this range, effectiveness plateaus or declines, leading to potential resource waste. The proposed framework provides a technical basis and practical strategy for guiding stormwater infrastructure planning in mountainous cities, balancing effectiveness with resource efficiency. Full article

A paradigm transition from centralized to decentralized energy systems has occurred, which has increased the deployment of renewable energy sources (RESs) in renewable energy communities (RECs), promoting energy independence, strengthening local resilience, increasing self-sufficiency, and moving toward CO₂ emission reduction. However, the erratic and unpredictable generation of RESs like wind, solar, and other sources make these systems necessary, and a lot of interest in energy storage systems is increasing because they have rapidly become the cornerstone of modern energy infrastructure, and there is a trend towards using more RESs and decentralization, resulting in increased self-sufficiency. Additionally, ESS is increasingly being installed at or close to the point of energy generation and consumption, like within residences, buildings, or community microgrids, instead of at centralized utility-scale facilities, referred to be decentralized. By storing and using energy in the same location, this localized deployment reduces transmission losses, facilitates quicker response to changes in demand, and promotes local autonomy in energy management. Since the production of renewable energy is naturally spread, decentralizing storage is crucial to optimizing efficiency and dependability. This article also focuses on energy storage systems, highlighting the role and scope of ESSs along with the services of ESSs in different parts of the power system network, particularly in renewable energy communities (RECs). The classification of various ESS technologies and their key features, limitations, and applications is discussed following the current technological and significant information trends and discussing the ESS types for the RECs with different options as per the capacity, like small, medium, and large scale. It covers the overall scenario and progress, like overall European ESS installed capacity, and the work relevant to ESSs in RECs with different aspects, following the literature review. Additionally, it draws attention to the gaps and significant challenges related to ESS technologies and their deployment. Key future suggestions have also been given as per the current trends of technological information and significant information that may affect those trends globally in the future and would be helpful in the growth of ESSs integration in RECs. The authors also suggest the role of the government, stakeholders, and supportive policies that can aid in the implementation of ESS technologies in RECs. Full article

Low-impact development (LID) facilities serve as a fundamental approach in urban stormwater management. However, significant variations in land use among different plots lead to discrepancies in runoff reduction demands, frequently leading to either the over- or under-implementation of LID infrastructure. To address this issue, we propose a cost-effective optimization framework grounded in the concept of “Capacity Trading (CT)”. The study area was partitioned into multi-scale grids (CT-100, CT-200, CT-500, and CT-1000) to systematically investigate runoff redistribution across heterogeneous land parcels. Integrated with the Sequential Least Squares Programming (SLSQP) optimization algorithm, LID facilities are allocated according to demand under two independent constraint conditions: runoff coefficient ($\phi$ ≤ 0.49) and runoff control rate ($\eta$ ≥ 70%). A quantitative analysis was conducted to evaluate the construction cost and reduction effectiveness across different trading scales. The key findings include the following: (1) At a constant return period, increasing the trading scale significantly reduces the demand for LID facility construction. Expanding trading scales from CT-100 to CT-1000 reduces LID area requirements by 28.33–142.86 ha under the $\phi$-constraint and 25.5–197.19 ha under the $\eta$-constraint. (2) Systematic evaluations revealed that CT-500 optimized cost-effectiveness by balancing infrastructure investments and hydrological performance. This scale allows for coordinated construction, avoiding the high costs associated with small-scale trading (CT-100 and CT-200) while mitigating the diminishing returns observed in large-scale trading (CT-1000). This study provides a refined and efficient solution for urban stormwater management, overcoming the limitations of traditional approaches and demonstrating significant practical value. Full article