Water, Air, & Soil Pollution最新文献

The concentration of ambient ammonia gas (NH₃(g)) in Kitakyushu, Japan was determined by a passive method for four years, with a mean value of 4.7 ppb. On a weekly basis, the NH₃(g) concentration fluctuated greatly; however, by applying a low-pass filter of 1 Hz/yr, a common feature in seasonal variation, a relative maximum for one year appeared in late spring to summer, and a relative minimum appeared in late autumn to winter. The two outliers with high NH₃(g) concentrations (16.5, 10.5 ppb) were observed in July and September in the second year, 2019. By using the backward trajectory analysis as well as comparing with other air pollutants from the viewpoint of time series and correlation coefficient, the high NH₃(g) concentration was considered to be due mainly to local meteorology and emissions. Five cases in which the NH₃(g) concentration was N.D. (not detected) reflected the low level in actual atmospheric condition; the PM_2.5 concentration also decreased synchronously during corresponding period. Comprehensively taking into account not only the large fluctuation but also the evaluation of high and low NH₃(g) concentrations, a statistically significant increasing trend of ca. 0.24 ppb/yr, providing an increasing rate of ca. 5.1%/yr during the study period which was comparable to the studies by satellite data analyses, was clarified. Wavelet analysis further showed three oscillation periods in NH₃(g) concentration on the scales of 30–50 weeks (w), 60–80 w, and 85–128 w. Moreover, the strongest oscillation occurred at 111 w with the variance of 3990, and three down-up conversions for the real part of wavelet coefficients were found, providing an overall cognition of NH₃(g) concentration variation to predict further changes.

The clean water crisis in Indonesia has recently increased due to wastewater pollution in groundwater. As an alternative, the use of seawater for clean water needs to be developed, considering that Indonesia has a very abundant area of sea water which is an alternative as a raw material for clean water resources. In this study, we fabricated TiO₂ nanoparticles (NPs) embedded in CA/PEG/Chitosan membranes for seawater desalination. The effect of TiO₂ NPs for high-performance of developed membranes was evaluated by reverse osmosis (RO) method to determine the unique characteristics and performance of membranes material for evaluating seawater desalination process. Preparation of CA/PEG/Chitosan membrane-embedded TiO₂ NPs was evenly dispersed into the CA/PEG/Chitosan membrane interlayer by blending method and printed on a glass surface to obtain a thin film developed membranes. The characterization and performance over developed membranes were evaluated to observe unique characteristic by adding TiO₂ NPs and its high-performance to reject salt content in seawater. Based on these results, the developed membranes were interestingly characterized by using FTIR spectrophotometer shows the presence of functional groups for organic and inorganic bonds such as C = O, -CH₃, NH₂, C-O, -OH, C-H, and Ti–O-Ti. The presence of TiO₂ NPs indicates the attachment of TiO₂ NPs in the membranes. In addition, a scanning electron microscope (SEM) was also confirmed to evaluate the morphological structure of without and CA/PEG/Chitosan-modified TiO₂ type (I) and (II), in which the pore size of CA/PEG/Chitosan is larger than membrane-embedded TiO₂ NPs. Moreover, XRD analysis also confirmed that TiO₂ NPs has shown amorphously structures formed on CA/PEG/Chitosan membrane, in which the TiO₂ NPs crystal size with 0.25 g of 2.87 nm and 0.5 g of 3.05 nm. Determination of seawater desalination and water flux has shown Ca/PEG/Chitosan membrane-modified TiO₂ NPs can increase salt rejection value but reduce membrane water flux value. The highest flux value is 29.4 L/m indicates by CA/PEG/Chitosan membrane, while the salt rejection value is 61.76% from CA/PEG/Chitosan membrane-embedded 0.5 g TiO₂ NPs. This study provides a new idea for preparing highly permeable and seawater desalination membranes of CA/PEG/Chitosan membrane-embedded TiO₂ NPs under the reverse osmosis method for producing clean water resources.

Aluminium-based coagulants are extensively used in water treatment, producing significant quantities of waste sludge (WTS), that poses challenges for landfill disposal. Eutrophication, mainly driven by phosphorus (P) enrichment from wastewater, remains a critical environmental concern in aquatic ecosystems. WTS contains substantial amounts of aluminium (Al), which exhibits a high affinity for phosphate. This study aimed to assess the phosphorus adsorption capacity (qmax) of WTS and its potential for agricultural use. The WTS samples were characterized using various analytical techniques. Kinetic and isothermal experiments were conducted using dried (105 °C) and calcined (650 °C) WTS samples. Characterization revealed crystallinity differences between dried WTS and calcined WTS Kinetic tests, indicating equilibrium times of 16 h for dried WTS and 1 h for calcined WTS. Isothermal tests showed maximum adsorption capacity values at pH 7 of 13.81 mgP g⁻¹ for dried WTS and 52.03 mgP g⁻¹ for calcined WTS, highlighting the enhanced phosphorus removal efficiency of calcined WTS. Phytotoxicity assessments demonstrated that dried and calcined WTS promoted enhancements in germination and root elongation of Lactuca sativa of 20 and 10%, respectively, suggesting its potential agricultural benefit. Therefore, WTS demonstrates promise for tertiary wastewater treatment, contributing to a circular economy by potentially reclaiming phosphorus-rich compounds for agricultural reuse.

The urban periphery and the villages around the river Aras are one of the most important agricultural areas in Iran. Against this background, the present study investigated the hydrochemistry of groundwater along the Aras River in Iran to assess the suitability of groundwater quality for agricultural irrigation. Water samples were taken from 34 groundwater sources in 2021 and 2022. The suitability of groundwater for irrigation was assessed using the sodium absorption ratio (SAR), residual sodium carbonate (RSC), magnesium absorption ratio (MAR), Kelly ratio (KR) and Wilcox classification. The Langelier Saturation Index (LSI) and the Ryznar Stability Index (RSI) were used to predict the corrosion and deposition behavior of the groundwater. The optical emission spectrometer with inductively coupled plasma was used to detect the heavy metals. Monte Carlo simulation was used to assess the non-carcinogenic and carcinogenic risks of these waters when used as drinking water. The average concentration of major ions follows for cations Na⁺˃ Ca²⁺˃ Mg²⁺˃ K⁺ and anions in both groups SO₄²⁻ > HCO₃⁻ > Cl⁻. The corrosion in all samples was found to have a low to considerable corrosion potential. The concentrations of the tested metals were within the range recommended by the WHO in most samples. In summary, it can be said that most of the groundwater sources in the area studied are appropriate for irrigation purposes. However, to reduce the risks associated with drinking, it is advisable to monitor water quality by locating sources of pollution and limiting the input of contaminants.

While several studies have employed coagulation-flocculation (CF) for textile wastewater (TW) treatment, conventional process optimization techniques cause insufficient pollution reduction and large sludge volume generation that deteriorate the environmental matrix and elevate the system’s operating cost. To avoid these drawbacks, this study focuses on optimizing an integrated CF/pyrolysis process using artificial intelligence technique and response surface methodology (RSM) for the dual benefit of TW treatment and biochar production. In the CF experiment, water hyacinth (WH) was employed as a bio-coagulant material for TW treatment under different pH, coagulant dosage, mixing speed, and settling time levels. Under the optimum CF conditions yielded by RSM and artificial neural network (ANN) models (initial pH: 5.5 vs. 5.7, WH dosage: 3.76 g/L vs. 3.5 g/L, settling time: 116 min vs. 102 min, and slow mixing speed: 25 rpm vs. 23 rpm), incomparable removal efficiencies for dye (87.3% vs. 91.3%) and turbidity (93.4% vs. 98.2%) were obtained. These removal efficiencies dropped to 83.5% and 87.6%, respectively, for operating the CF process using unoptimized operating factors. The pyrolysis of post-coagulation sludge yielded a carbon-rich biochar material characterized by a porous structure and abundant cationic microelements. The integrated performance of the CF/pyrolysis scheme under ANN-based optimal conditions achieved a shorter payback period of 5.2 years compared to RSM (5.7 years) and unoptimized (7.9 years) conditions. Furthermore, the optimized scheme supported several sustainable development goals that complied with clean water, good health, and climate change mitigation.

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In this paper, a novel graphene oxide/β-cyclodextrin composite (GO/β-CD) adsorbent was synthesized for the effective simultaneous removal of dyes. GO and GO/β-CD were characterized using BET, SEM, FT-IR, Raman, and XRD techniques. GO/β-CD has a BET specific surface area of 0.25 m²/g. The surface of GO/β-CD contains a significant number of reactive groups, such as carboxyl groups, which enable the effective adsorption of methylene blue (MB). The adsorption of GO/β-CD on methylene blue (MB) in aqueous solution was also investigated kinetically and thermodynamically. The kinetic and thermodynamic parameters of the reaction were calculated. Based on the experimental results, the adsorption reaction was determined to be a spontaneous endothermic reaction. The adsorption of MB on GO/β-CD best fit the Langmuir model based on the results of the adsorption isotherm model fitting. The maximum adsorption capacity of the composite was 434.78 mg/g. The GO/β-CD adsorbent was highly efficient at adsorbing cationic dyes, and its performance remained consistently high after six cycles. Thus, GO/β-CD offers the advantages of nontoxicity, excellent adsorption and regeneration properties, and great potential for treating real and simulated wastewater from various industries.

Reactive transport models (RTMs) are widely adopted supporting tools for the design and management of aquifer in-situ bioremediation systems. However, their use has not been yet fully demonstrated for the design and management of operational-scale sequential bioremediation system (SBSs). In this work, a multispecies RTM was developed to reproduce an SBS coupled to a pump-and-treat (P&T) system in a chloroethene-polluted alluvial aquifer of Northern Italy. It is one of the first-ever documented applications of multispecies process-based RTM to simulate an operational-scale SBS. Two different model configurations were created to study the importance of adopting a more homogeneous or heterogeneous spatial distribution of transport parameters. The first configuration embedded three different reaction zones (RZs), each one described by spatially—invariant first-order reaction rates ((k)) simulating parent-daughter transformation of chloroethenes (PCE→TCE→DCE→VC). The second configuration embedded a spatially variant distribution of reaction rates within the three RZs, resulting in a more heterogeneous parametrization. Given the larger number of fitting parameters, the more heterogeneous model provided a better match of the field observations. Compared to it, calibrated (k) obtained from the more homogeneous model were largely underestimated for more-chlorinated compounds (PCE, TCE) and overestimated for less-chlorinated compounds (DCE, VC). The heterogeneous model showed that the capacity of the SBS to degrade the chemicals varied significantly across the different site areas, a feature not captured by the homogeneous model, and which could have important implications regarding the potential closure of selected P&T wells.

The composition and source analysis of dissolved organic matter (DOM) in sewage outfall into the sea is an effective means of pollutant traceability, which is of great significance to the ecological environment protection in coastal areas. This paper selects Dongguan, an important coastal industrial city in China’s Pearl River, for research. Water samples from 42 sewage outfalls into the sea were measured by three-dimensional fluorescence spectroscopy (3D-EEM). Combined with fluorescence characteristic parameters, similarity analysis and parallel factor analysis (PARAFAC), the spectral characteristics, DOM composition and source were analyzed. The average values of fluorescence parameters fluorescence index (FI), biological index (BIX) and humification index (HIX) were 1.80, 0.94 and 0.55, respectively. The overall PARAFAC analysis found that DOM in the sewage outfall of Dongguan was mainly composed of two fluorescent components, namely tyrosine-like (C1) and humus-like (C2), where tyrosine-like fluorescence was higher than humus-like. This indicates that DOM comes from both terrestrial and endogenous biological activities, but endogenous sources are the primary sources. The similarity analysis divided sewage outfalls into four categories, namely urban rainwater drainage characteristics, typical urban sewage, Jiulong paper-related wastewater and aquaculture water in fish ponds. At the same time, in the PARAFAC analysis, the fluorescence components of 14 urban rainwater outfalls were consistent with the overall analysis results. There are 3 effective parallel factor fluorescence components in 23 outfalls most likely to be contaminated by domestic sewage, namely tyrosine (C1) Humus-like (C2) and tryptophan (C3), C3 components in the characterization of the protein fluorescent tryptophan substance region appeared a strong response peak, belonging to the source pollution, consistent with similarity analysis results. This study suggests that the same source sewage outfalls should be classified management, strengthen the source tracing of sewage outfalls into the sea in neighboring cities, and build a collaborative pollution control system for river basins, estuaries and coastal.

Microplastics (MPs) pollution in soil have emerged as a significant environmental concern, infiltrating ecosystems and posing threats to ecological, plants, human, and animal health. We aim to provide a comprehensive understanding of microplastics, exploring their types, sources, pathways, and impacts across different environmental compartments. Begins with an introduction to microplastics, this review offers details on their classification and examines their omnipresence in aquatic and across other environments highlighting their persistent nature and complex pathways. It culminates the urban runoff, industrial discharges, anthropogenic activities, and agricultural inputs as major contributors, underscoring the need for targeted intervention strategies. The review underscores the detrimental effects of microplastics on aquatic life, soil fertility, and food safety, while also addressing the broader societal implications, including economic costs and public health concerns. Sampling and detection methods for microplastics are critically reviewed, covering advanced techniques and technologies that enable accurate identification and quantification of these pollutants. Overall, underscoring the dynamic nature of the microplastic pollution by synthesizing current knowledge and advancements, this review calls for the long-term monitoring and adaptive management strategies for future research, policy-making, and public initiatives towards a sustainable and microplastic-free environment.

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Industrial wastewater poses significant environmental and health risks due to its diverse pollutant composition. This study investigates the effectiveness of coagulation-flocculation treatment using aluminum sulfate (alum) for treating paper and pulp wastewater. The results highlight the significance of pre-biological treatment, pH optimization, alum dosages, and pre-filtration in enhancing removal efficiency for total solids (TS), total dissolved solids (TDS), total organic carbon (TOC), and ion concentrations. Pre-filtration significantly improved treatment performance, resulting in a 67% reduction in TS. Ion chromatography provided insights into post-treatment ion concentration changes. Under optimal conditions, including a treatment with 500 ppm alum dosage, alkaline pH of 11, and pre-filtration, the highest TS and TOC removal efficiencies were (52%) and (77%), while TDS reduction reached a maximum of 40% at lower alum dosages (100 mg/L). This study contributes crucial insights into optimizing alum coagulation-flocculation for paper and pulp wastewater treatment, offering potential solutions to mitigate industrial pollution and secure water resources.

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