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1.
MethodsX ; 12: 102626, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38559383

RESUMO

The transition from conventional landfill-centric waste management to resource-centric methodologies necessitates an enhanced comprehension of municipal solid waste (MSW) composition and its inherent value. Existing methodologies documented in the literature exhibit a lack of standardization, impending the formulation of a systematic engineering approach for MSW characterization and valuation. This study introduces a methodology specifically tailored to discern the composition of waste origination from urban households and evaluate its recyclability within the confines of a circular economy framework, Employing a volume-based measurement approach, aims to estimate the recycling value of waste materials. The study's outcomes contribute significantly to quantifying the potential recycling value that accrues to society. Furthermore, the validation of the proposed protocol elucidates the dynamic nature of recyclable value as it traverses the intricate pathways of the waste supply chain. This insight facilitates the formulation of commercial models grounded in circular economy principles for the effective management of household solid waste. Empirical findings reveal that the total recycling value fluctuates within the range of USD 3.39 and USD 5.76 per cubic meter of waste volume, contingent upon the specific waste composition at the experiment site. Additionally, the proposed methodology uncovers the nuanced variability in MSW composition and recycling value across diverse household collection patterns, identifying mixed plastic, paper, cardboard, mixed MSW, and clothing as primary constituents. The application of this methodology extends beyond mere quantification, providing a foundational framework for simulating the latent recycling value embedded within MSW samples. This, in turn, offers invaluable support to strategy developers, policymakers, and entrepreneurial ventures engaged in the sustainable management of household solid waste. In essence, this study establishes the groundwork for a comprehensive understanding of MSW composition and its recyclability, facilitating informed decision-making in the pursuit of a circular economy.•Novel methodology based on one cubic meter (1m3) composition analysis of Municipal Solid Waste (MSW).•A new method to evaluate the recycling value of Municipal Solid Waste.•A basis for business model development for the waste-to-resource conversion model.

2.
Environ Health Insights ; 18: 11786302241242231, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38559898

RESUMO

Introduction: Municipal solid waste collectors are at risk of experiencing work-related health problems due to the waste they handle and the physical effort they put in. Work-related injuries among domestic waste collectors have been the subject of scant research in developing nations. Therefore, it is necessary to describe work-related injuries in these subpopulation groups. Objective: This study aimed to determine the prevalence and associated factors of work-related injury among municipal solid waste collectors in Hawassa city, Southern Ethiopia. Methodology: A cross-sectional study was conducted from January 11 to 30, 2022, with all the registered municipal solid waste collectors (411). Three diploma environmental health professionals assisted in collecting data using a pretested structured interviewer-administered questionnaire; 1 Bachelor of Science environmental health professional served as a supervisor. Statistical Package for the Social Sciences (SPSS) version 20.0 was used to enter, clean, code, and analyze the data. Associations between independent and dependent variables were assessed, and the strength of the associations was presented by using Adjusted Odds Ratio (AOR) and 95% confidence intervals (CI). According to the bivariable analysis, all independent variables associated with a P-value <.25 were entered into a multivariable logistic regression model. Variables in the multivariable regression analysis were considered significant if their P-value was less than 0.05. Results: In this study, the prevalence of work-related injuries within the last 30 days was 12.9% (95% CI: 9.5, 16.3), while the prevalence over the last 12 months was 59.4% (95% CI: 54.7, 64.0). After adjusting for possible confounding factors, age 18 to 24 years [AOR = 1.72;95% CI: (1.07, 2.76)], lack of personal protective equipment (PPE) utilization [AOR = 2.30; 95% CI: (1.44, 3.68)], chewing khat (yes) [AOR = 2.32;95% CI: (1.32, 4.08)], drinking alcohol (yes) [AOR = 1.80; 95% CI: (1.003, 3.24)] and job dissatisfaction [AOR = 2.26, 95% CI: (1.44, 3.54)] were shown to be significantly associated with work-related injury. Conclusion: The prevalence of work-related injuries was high. Age 18 to 24 years, chewing khat, drinking alcohol, lack of PPE utilization, and job dissatisfaction were significantly associated with work-related injury. Based on the findings of this study, we suggest that addressing these risk factors could help to reduce work-related injuries.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38558342

RESUMO

The use of electronic waste in cement concrete as a fibre additive has proven to be very promising for improving mechanical characteristics and developing sustainable construction materials to reduce the waste dumped in landfills. The following study investigated the effect of electronic waste (printed circuit boards (PCBs)) on the mechanical properties of concrete and predicted the same properties with an appropriate machine learning technique. PCB fibres 45 mm in length and 1.5 mm in width were manufactured and added as fibre additions to two sets of concrete mixes with and without silica fume. A 10% volume replacement of cement was substituted with silica fume (SF) to enhance the characteristics of PCB fibre-reinforced concrete and minimize cement consumption. The study included an evaluation of the fresh properties and mechanical characteristics after a 28-day curing period; thereafter, the results were compared and studied using the Levenberg-Marquardt backpropagation algorithm for predictions. The results show that the mechanical properties improved up to a 5% addition of PCB fibres, resulting in strengths of 63.55 MPa and 69.92 MPa for mixtures of PCB5% and SFPCB5%, respectively. A similar trend was achieved for other properties, such as the tensile and flexural strengths. The results of the ANN model predicted values with R2 values ranging from 0.94 to 0.99, indicating the efficacy of the model.

4.
Waste Manag Res ; : 734242X241242697, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38600751

RESUMO

Managing municipal solid waste (MSW) is a critical for Indonesia, as the country produces a substantial amount of waste annually. However, Indonesia's recycling rate remains limited, less than 25% of its waste, with the rest ending up in landfills. To address this, waste banks have emerged as a community-based solution to enhance MSW management through recycling. Although waste banks currently contribute only 7% to recyclable waste management, they hold promising potential, especially considering their close ties to households, the primary waste producers in Indonesia. Unfortunately, documentation of waste bank successes in Indonesian regencies is scarce, as most success stories are limited to major cities. This article conducts a literature review on waste bank implementations across various regencies, evaluating their accomplishments, obstacles and potential contributions to local MSW management. The review draws upon scholarly publications and various government reports, regulations and websites dedicated to updates on waste bank activities. Waste banks play a crucial role in enhancing environmental quality by promoting proper waste disposal and reducing landfill waste. They create economic opportunities, increasing income for both customers and administrators. Additional services, such as banking facilities encompassing savings, loans, daily necessities and bill payments, amplify their significance. To fully harness the potential of waste banks, support is imperative. Establishing adequate infrastructure and providing capacity-building for administrators are essential. Although regulatory frameworks offer opportunities, the impact of regency-level regulations on waste bank growth varies and necessitates further examination. Support mechanisms should be tailored to align with local characteristics and requirements.

5.
Artigo em Inglês | MEDLINE | ID: mdl-38589589

RESUMO

Inappropriate waste management is a considerable ecological risk, leading to detrimental effects on the soil, air, and water quality. It is imperative to address these concerns promptly to minimize the repercussions of solid waste on public health and the ecosystem. It is evident that the level of economic growth directly impacts waste generation. This study intends to use the life cycle assessment (LCA) technique to evaluate the environmental impacts of four alternative municipal solid waste (MSW) management scenarios in Peshawar City, Pakistan. The goal is to discover an option that is both sustainable and minimizes environmental damage. The study examined the system boundaries encompassing the collection and transportation of MSW, along with its processing and final disposal, employing composting, anaerobic digestion (AD), material recovery facilities (MRF), and landfill methods. Comprehensive field studies and an in-depth literature review provided the data regarding Peshawar's existing MSW management system and the proposed scenarios, all of which was inventoried in the OpenLCA 1.10.3 database. Following data collection, the CML-IA technique was employed to analyze the data, measuring the environmental footprint in terms of climate change potential, human toxicity, acidification potential, photochemical oxidation, and eutrophication. A sensitivity analysis was also performed to identify the influence of varying recycling rates on the environmental strain correlated with the proposed scenarios. The analysis results indicated that scenario S2, which combined composting, landfilling, and MRF, exhibited the least environmental impact compared to the other considered scenarios. Furthermore, the sensitivity analysis reflected an inverse correlation between alterations in the recycling rate and the total environmental impact. To counter the environmental problems arising from waste generation, it is essential to incorporate principles of the circular economy into the MSW management approach.

6.
Artigo em Inglês | MEDLINE | ID: mdl-38592627

RESUMO

Indirect carbonation of steel slag is an effective method for CO2 storage, reducing emissions, and promoting cleaner production in the steel industry. However, challenges remain, such as low Ca2+ leaching rates and slag management complexities arising from variations in mineral compositions. To address this, a high-temperature modification process is proposed to alter the mineral composition and facilitate the synergistic utilization of calcium and iron. This study delves into the effects of various solid waste modifications on the leaching of Ca2+ and the total iron content within steel slag. Results show that high-basicity modified slag forms Ca2(Al, Fe)2O5, reducing calcium leaching. Low-alkalinity modified slag produces calcium-rich aluminum minerals and also reduces the leaching of Ca2+ ions. At a basicity of 2.5, coal gangue, fly ash, and blast slag achieve maximum Ca2+ leaching rates of 88.93%, 89.46%, and 90.17%, respectively, with corresponding total iron contents of 41.46%, 37.72%, and 35.29%. Upgraded coal gangue exhibits a 50.02% increase in calcium leaching and a 15.58% increase in total iron content compared to the original slag. This enhances CO2 fixation and iron resource utilization. Overall, the proposed indirect carbonation and iron enrichment modification offer a novel approach for the resource utilization and environmental stability of steel slag.

7.
Chemosphere ; : 142077, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38643843

RESUMO

Organic fraction of municipal solid waste (OFMSW) and waste activated sludge (WAS) are the most produced organic waste streams in urban centres. Their anaerobic co-digestion (AcoD) allows to generate methane (CH4) and digestate employable as renewable energy source and soil amendment, respectively, fully in accordance with circular bioeconomy principles. However, the widespread adoption of such technology is limited by relatively low CH4 yields that fail to bridge the gap between benefits and costs. Among strategies to boost AcoD of OFMSW and WAS, use of conductive materials (CMs) to promote interspecies electron transfer has gained increasing attention. This paper presents one of the few experimental attempts of investigating the effects of four different carbon(C)-based CMs (i.e., granular activated carbon - GAC, graphite - GR, graphene oxide - GO, and carbon nanotubes - CNTs) separately added in semi-continuous AcoD of OFMSW and thickened WAS. The presence of C-based CMs has been observed to improve CH4 yield of the control process. Specifically, after 63 days of operation (concentrations of GAC and GR of 10.0 g/L and of GO and CNTs of 0.2 g/L), 0.186 NL/gVS, 0.191 NL/gVS, 0.203 NL/gVS, and 0.195 NL/gVS of CH4 were produced in reactors supplemented with GAC, GR, GO, and CNTs, respectively, compared to 0.177 NL/gVS produced in the control process. Likewise, at the end of the test (i.e., after 105 days at concentrations of C-based CMs half of the initial ones), CH4 yields were 0.193 NL/gVS, 0.201 NL/gVS, 0.211 NL/gVS, and 0.206 NL/gVS in reactors supplemented with GAC, GR, GO, and CNTs, respectively, compared to 0.186 NL/gVS of the control process. Especially with regard to GR, GO, and CNTs, results obtained in the present study represent a significant advance of the knowledge on the effects of such C-based CMs to realistic and scalable AD process conditions respect to previous literature.

8.
Chemosphere ; 357: 142062, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38636915

RESUMO

Coffee processing wastes, such as solid (pulp and husk) and wastewater, co-digested with industrial brewery wastewater, serve as excellent substrates for generating methane in the anaerobic digestion process. This study compared methane production using different compositions of cattle manure (CM) and granular sludge from an Upflow Anaerobic Sludge Blanket (UASB) reactor used in poultry wastewater treatment (GS). Four anaerobic batch reactors (500 mL) were assembled, A (50% CM and 50% GS), B (60% CM and 40% GS), C (70% CM and 30% of GS) and D (60% CM and 40% GS). Equal concentrations of substrates were added to all reactors: pulp and husk pretreated by hydrothermolysis (1 g L-1), coffee (10 g COD L-1) and brewery (1.5 g COD L-1) wastewaters. Assays A, B and C were supplemented with 2 g L-1 of yeast extract, except for assay D. The reactors were operated at 37 °C and pH 7.0. In assay B, the highest CH4 production of 759.15 ± 19.20 mL CH4 g-1 TS was observed, possibly favored by the synergistic interactions between cellulolytic bacteria Christensenellaceae_R-7_group and Methanosaeta archaea, as inferred by genes encoding enzymes related to acetoclastic methanogenesis (acetyl-CoA synthetase). Consequently, the electricity production potential of assay B (45614.08 kWh-1 year-1) could meet the energy demand of a farm producing coffee and beer, contributing to a positive energy balance concerning methane generation.

9.
Materials (Basel) ; 17(7)2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38612220

RESUMO

The disposal of electroplating sludge (ES) is a major challenge for the sustainable development of the electroplating industry. ESs have a significant environmental impact, occupying valuable land resources and incurring high treatment costs, which increases operational expenses for companies. Additionally, the high concentration of hazardous substances in ES poses a serious threat to both the environment and human health. Despite extensive scholarly research on the harmless treatment and resource utilization of ES, current technology and processes are still unable to fully harness its potential. This results in inefficient resource utilization and potential environmental hazards. This article analyzes the physicochemical properties of ES, discusses its ecological hazards, summarizes research progress in its treatment, and elaborates on methods such as solidification/stabilization, heat treatment, wet metallurgy, pyrometallurgy, biotechnology, and material utilization. It provides a comparative summary of different treatment processes while also discussing the challenges and future development directions for technologies aimed at effectively utilizing ES resources. The objective of this text is to provide useful information on how to address the issue of ES treatment and promote sustainable development in the electroplating industry.

10.
Sci Total Environ ; 927: 172312, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38599403

RESUMO

The surge in urban development has resulted in a substantial accumulation of construction solid waste (CSW). However, prevailing identification methods of CSW remain predominantly two-dimensional in scope and need to be more efficient. This study employs an approach, combining simulation and experimental analyses, to delve into the factors influencing the electromagnetic scattering characteristics of CSW, investigating the feasibility of employing Synthetic Aperture Radar (SAR) to recognize CSW. The findings show that the computational time of MLFMM and PO is only 3.28 % and 0.029 % of MM among different simulation methods. The results underscore the collective impact of material types, surface structures, and curvature on the scattering characteristics of CSW. The difference in average intensity between different materials can reach up to 13 dB. Exploiting these distinctions in scattering enables the precise identification of high-value waste components, such as intact bricks and steel bars, within the intricate landscape of CSW.

11.
Sci Total Environ ; 928: 172450, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38615774

RESUMO

The distribution of potentially toxic elements (PTEs) such as zinc (Zn), copper (Cu), lead (Pb), nickel (Ni), cadmium (Cd), and chromium (Cr), their potential bioavailability, extent of contamination and potential risk of dumpsite and surrounding soil samples were appraised. Three (3) soil samples were collected randomly from within the dumpsite and three (3) soil samples were also obtained 50 m away from the perimeter fence of the dumpsite. PTEs in the bulk and fractionated portions were determined using inductively coupled plasma - optical emission spectrometry (ICP-OES). The results showed that the concentrations of all the PTEs analysed were higher in the dumpsite soil samples than the surrounding samples, suggesting an impact of the dumpsite activities on the soil. The distribution of PTEs varied significantly within the different fractions of both the surrounding and dumpsite soils and their presence were more of anthropogenic than geogenic. The calculated contamination factor/pollution load index (CF/PLI) revealed that the surrounding soil samples fell within the range of moderate contamination, except for Cu and Cr which showed very high contamination. Cd showed the highest value (60.4) for potential ecological risk index (PERI) at the surrounding area. However, the value of Cd in the surrounding soil samples indicated a low ecological risk. The total concentrations of the PTEs were lower than their corresponding target values for both national and international standards, except for Cd (0.15 mg/kg) and Cu (37.3 mg/kg). The study concluded that the dumping of various wastes at the dumpsite was found to be a contributing factor to PTEs contamination of soil at the study area. Hence, an engineered landfill for Akure metropolis is recommended to replace the existing practice.

12.
J Environ Manage ; 358: 120924, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38636416

RESUMO

Solid waste is increasing rapidly worldwide. In this study, the solid waste (household waste, construction and demolition waste and industrial waste) management systems are treated as reverse supply chain to analyze the critical operational issues based on complex adaptive system theory. At the single-layer, the complexity of the various nodes at a layer arises from rational decision-making and behavioral heterogeneity. The solid waste generation layer is employed as an example to investigate the complexity of node behavioral decisions. Regression analysis results reveal that both endogenous (Attitude, Subjective norm, and Perceived behavioral control) and exogenous factors (Economic incentive, Government supervision, Technical support) positively influence sorting behavior. The effect of Economic incentive (ß=0.327P<0.001) and Attitude (ß=0.249P<0.001) on sorting behavior are the largest. In the multi-layer system, different layers communicate with each other through the material and financial flows and have cross-layer impacts. An agent-based model is developed to investigate the multi-layer feedforward influence mechanism of changes in key layers (e.g., sorting rate, disposal rate) and the material and financial flows adaptive adjustment direction of the solid waste reverse supply chain. High rate of participation and accuracy of source sorting can shorten material flow paths and reduce storage and transportation costs. The increase in disposal rate encourages the transition of solid waste from backfill to resource utilization. This study provides a practice reference for solid waste reverse supply chain and related enterprises managers.

13.
Environ Pollut ; : 124011, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38641034

RESUMO

The clean and efficient utilization of municipal solid waste (MSW) has attracted increasing concerns in recent years. Pyrolysis of MSW is one of the promising options due to the production of high-value intermediates and the inhibition of pollutants at reducing atmosphere. Herein, the formation behavior of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) during MSW pyrolysis and incineration was experimentally investigated and compared. The influence of reaction temperature, CaO addition, and redox atmosphere on PCDD/Fs formation were compared and discussed. The results showed as the pyrolysis temperature increased, the mass concentration and international toxicity equivalence quantity of PCDD/Fs initially peaked at ∼750 oC before declining. Most of the generated PCDD/Fs were concentrated in the liquid and gaseous products, accounting for ∼90% of the total. Among liquid products, octachlorodibenzo-p-dioxin (O8CDD), 2,3,4,7,8-pentachlorodibenzofuran and 1,2,3,4,6,7,8-heptachlorodibenzofuran (H7CDF) were the most crucial mass concentration contributors, while in gas products, high-chlorinated PCDD/Fs, such as O8CDD, octachlorodibenzofuran (O8CDF) and 1,2,3,4,6,7,8-H7CDF were predominant. Compared to incineration, the formation of PCDD/Fs was 7-20 times greater than that from pyrolysis. This discrepancy can be attributed to the hydrogen-rich and oxygen-deficient atmosphere during pyrolysis, which effectively inhibited the Deacon reaction and the formation of C-Cl bonds, thereby reducing the active chlorine in the system. The addition of in-situ CaO additives also decreased the active chlorine content in the system, bolstering the inhibiting of PCDD/Fs formation during MSW pyrolysis.

14.
Environ Monit Assess ; 196(5): 450, 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38613635

RESUMO

Unscientific dumping of municipal solid waste (MSW) is a common practice in Kashmir. To have an environmentally friendly and sustainable waste management system, MSW was collected from nine study locations of this region. They were air-dried, then oven-dried at 105 °C for 24 h, segregated, and characterized for various components. The overall average organic waste was > 55%, plastic waste about 17%, inert material about 10%, paper 9%, and cloth waste 7%. The calorific value of paper and plastic wastes exhibited was 4910 kcal/kg, while organic waste had a calorific value of 1980 kcal/kg. The proximate analysis showed that the moisture content ranged from 16 to 29%, volatile matter ranged from 49 to 72%, ash content ranged from 0.03 to 5%, and fixed carbon ranged from 5 to 20%. In S7, the volatile matter content recorded the lowest value at 49.15%, while in S5, the volatile matter content was notably higher at 71.84%, indicating easier ignition. Further, elemental analysis revealed that the major elements in MSW were carbon and oxygen, 53% and 37%, respectively, with small traces of heavy metals with an average of 0.02% cadmium (Cd) and 0.006% lead (Pb). Moreover, field emission scanning electron microscopy (FESEM) micrographs provided confirmation that the majority of components in the MSW exhibited either partial or complete degradation, resulting in a rough surface texture. In addition, the presence of silica and other silicate groups was also detected. Fourier transform infrared spectroscopy (FT-IR) analysis revealed that the main functional groups were alcohol. In the X-ray diffraction (XRD) analysis, all the major mineral phases were detected between 20 and 30° 2θ, except for the peaks at 50-60° 2θ in S3 and S9 where catalysts such as zeolite Y and zeolite X were detected. Overall, the MSW had low moisture content but higher calorific value, making it a viable feedstock.


Assuntos
Resíduos Sólidos , Zeolitas , Espectroscopia de Infravermelho com Transformada de Fourier , Monitoramento Ambiental , Índia , Carbono , Microscopia Eletrônica de Varredura
15.
Waste Manag ; 181: 145-156, 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38608529

RESUMO

Landfill disposal is a major approach of disposing municipal solid waste (MSW) in China. In order to explore the impact of volatile organic compounds (VOCs) generated by landfill on the air quality of regional environment, Jiangcungou landfill in Xi'an and its surrounding area were taken as a research object to analyze the spatial distribution and seasonal variation patterns of non-methane hydrocarbon (NMHC) and VOCs components through seasonal sampling of regional NMHC concentration and VOCs concentration (116 species). CALPUFF model was adopted to analyze the regional dispersion characteristics of NMHC on landfill. In addition, propylene equivalent concentration (PEC) and maximum incremental reactivity (MIR) methods were used to estimate O3 formation potential of the landfill, while fraction aerosol coefficient (FAC) and SOA potential (SOAP) methods were used to estimate SOA formation potential of the landfill. It was indicated that, the component with the highest concentration of VOCs on the working surface and the surrounding area of landfill was p + m-xylene (41.0 µg/m3) and halohydrocarbon (111.2 µg/m3-156.3 µg/m3), respectively. The component with the greatest impact on the surrounding air was acetone, which accounts for 75 %-87 % of the corresponding substance concentration on the landfill. In summer, the surrounding area was affected most by NMHC from landfill, whose emissions contributed 9.5 mg/m3 to the surrounding area. The component making the largest contribution to O3 formation was p + m-xylene (8 %-24 %), while ethylbenzene was the component making the largest contribution to SOA formation (20 %-24 %).

16.
Chemosphere ; 355: 141871, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38570052

RESUMO

Recycling solid waste for preparing sulfoaluminate cementitious materials (SACM) represents a promising approach for low-carbon development. There are drastic physical-chemical reactions during SACM calcination. However, there is a lack of research on the flue gas pollutants emissions from this process. Condensable particulate matter (CPM) has been found to constitute the majority of the primary PM emitted from various fuel combustion. In this study, the emission characteristics of CPM during the calcination of SACM were determined using tests in both a real-operated kiln and laboratory experiments. The mass concentration of CPM reached 96.6 mg/Nm3 and occupied 87% of total PM emission from the SACM kiln. Additionally, the mass proportion of SO42- in the CPM reached 93.8%, thus indicating that large quantities of sulfuric acid mist or SO3 were emitted. CaSO4 was one key component for the formation of main mineral ye'elimite (3CaO·3Al2O3·CaSO4), and its decomposition probably led to the high SO42- emission. Furthermore, the use of CaSO4 as a calcium source led to SO42- emission factor much higher than conventional calcium sources. Higher calcination temperature and more residence time also increased SO42- emission. The most abundant heavy metal in kiln flue gas and CPM was Zn. However, the total condensation ratio of heavy metals detected was only 40.5%. CPM particles with diameters below 2.5 µm and 4-20 µm were both clearly observed, and components such as Na2SO4 and NaCl were conformed. This work contributes to the understanding of CPM emissions and the establishment of pollutant reduction strategies for waste collaborative disposal in cement industry.


Assuntos
Poluentes Atmosféricos , Poluentes Ambientais , Metais Pesados , Material Particulado/análise , Poluentes Atmosféricos/análise , Resíduos Sólidos , Cálcio
17.
Artigo em Inglês | MEDLINE | ID: mdl-38632194

RESUMO

In this study, three different univariate municipal solid waste (MSW) disposal rate forecast models (SARIMA, Holt-Winters, Prophet) were examined using different testing periods in four North American cities with different socioeconomic conditions. A review of the literature suggests that the selected models are able to handle seasonality in a time series; however, their ability to handle outliers is not well understood. The Prophet model generally outperformed the Holt-Winters model and the SARIMA model. The MAPE and R2 of the Prophet model during pre-COVID-19 were 4.3-22.2% and 0.71-0.93, respectively. All three models showed satisfactory predictive results, especially during the pre-COVID-19 testing period. COVID-19 lockdowns and the associated regulatory measures appear to have affected MSW disposal behaviors, and all the univariate models failed to fully capture the abrupt changes in waste disposal behaviors. Modeling errors were largely attributed to data noise in seasonality and the unprecedented event of COVID-19 lockdowns. Overall, the modeling errors of the Prophet model were evenly distributed, with minimum modeling biases. The Prophet model also appeared to be versatile and successfully captured MSW disposal rates from 3000 to 39,000 tons/month. The study highlights the potential benefits of the use of univariate models in waste forecast.

18.
Sci Rep ; 14(1): 8910, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632259

RESUMO

Landfill leachate forms when waste-inherent water and percolated rainfall transfer are highly toxic, corrosive, acidic, and full of environmental pollutants. The release of leachate from municipal solid waste (MSW) landfill sites poses a severe hazard to human health and aquatic life. This study examined the impact of leachate from Delhi's Ghazipur landfill on the nearby groundwater quality. Analysis of leachate samples was done to determine various parameters such as total dissolved solids (TDS), hardness, alkalinity, electrical conductivity, pH, BOD5, COD, nitrate, sulphate, chloride and iron, and presence of coliform bacteria. Significant dissolved elements (22,690-34,525 mg/L) were observed in the samples, indicated by the high conductivity value (1156-1405 mho/cm). However, a stable pH range (6.90-7.80) of leachate samples was observed due to high alkalinity concentrations between 2123 and 3256 mg/L. The inverse distance weighing (IDW) interpolation tool from QGIS 3.22.7 developed spatial interpolated models for each parameter across the Ghazipur area. The IDW interpolated graphs of various parameters over the whole study area confirmed these contaminations. In addition, leachate and groundwater samples were physio-chemically analyzed, and temporal fluctuation in landfill waste has also been studied. The temporal fluctuation results showed that when heat is produced, transmitted, and lost throughout the waste system, the maximum temperature position fluctuates over time. The findings of this study highlight the critical importance of landfill management in reducing groundwater contamination from MSW leachate.

19.
Plant Methods ; 20(1): 54, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632634

RESUMO

Improper management of agricultural and industrial cotton wastes causes environmental pollution and worsens the climate change challenge. Green recycling of cotton could contribute to a circular economy. One of the economic values of cotton wastes lies in their bioactive components. Two types of cotton wastes-agricultural and industrial-of the species Gossypium barbadense L. Giza 95 were targeted in the current study, aiming to maximize their medicinal value and investigate the anti-inflammatory, hepatoprotective, and antioxidant activities of their phytochemical extracts. Phytochemical extraction was performed using different solvents extraction. An anti-inflammatory effect was tested in carrageenan-induced acute edema in a rat paw model. A carbon tetrachloride chronic model of liver injury was used for the assessment of hepatoprotective potential. Liver enzymes (AST and ALT), oxidative stress markers (MDA and GSH), inflammatory biomarkers (C-reactive protein), and histopathological features were investigated. As a result, ethyl acetate proved to be the solvent of best choice to extract the gossypin polyphenolics, where the extracted amount reached 14,826.2 µg/g, followed by butanol (8751.4 µg/g extract). The chloroform (CHCL3) fraction showed the highest amounts of gossypol (190.7 µg/g extract), followed by petroleum ether. Cotton waste's composition analysis showed a wide range of components, including 33 metabolites such as gossypetin, polyphenolics, and other metabolites that possess therapeutic effects. Both chloroform extract and industrial waste extracts showed superior anti-inflammatory and hepatoprotective effects in comparison to other extracts. All tested extracts (ethyl acetate, chloroform, and industrial waste) showed proper antioxidant activities.

20.
Sci Total Environ ; : 172658, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38657813

RESUMO

Per- and poly-fluoroalkyl substances (PFAS) are a class of synthetic chemicals known for their widespread presence and environmental persistence. Carbon-fluorine (C-F) bonds are major components among PFAS and among the strongest organic bonds, thus destroying PFAS may present significant challenge. Thermal treatment such as incineration is an effective and approved method for destroying many halogenated organic chemicals. Here, we present the results of existing studies and testing at combustion-based thermal treatment facilities and summarize what is known regarding PFAS destruction and mineralization at such units. Available results suggest the temperature and residence times reached by some thermal treatment systems are generally favorable to the destruction of PFAS, but the possibility for PFAS or fluorinated organic byproducts to escape destruction and adequate mineralization and be released into the air cannot be ruled out. Few studies have been conducted at full-scale operating facilities, and none to date have attempted to characterize possible fluorinated organic products of incomplete combustion (PICs). Further, the ability of existing air pollution control (APC) systems, designed primarily for particulate and acid gas control, to reduce PFAS air emissions has not been determined. These data gaps remain primarily due to the previous lack of available methods to characterize PFAS destruction and PIC concentrations in facility air emissions. However, newly developed stack testing methods offer an improved understanding of the extent to which thermal waste treatment technologies successfully destroy and mineralize PFAS in these waste streams.

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