International Journal of Environmental Science and Technology最新文献

In this research, a three-stage continuous reactor involving an electrocoagulation (EC) unit and dual-step simultaneous horizontal sand filtration (SF) was designed to achieve the maximum potential of the EC-flocculation method for the denitrification process. The system employs a hybrid electrode arrangement with Fe cathodes and Al anodes, operating at a head difference of 1.5 cm. A set of 30 experiments according to the central composite design (CCD)-based response surface methodology (RSM) was designed to optimize the effects of the main parameters, including initial nitrate concentration (90-450 mg/l), process time (10-130 min), initial pH (2-10) and current intensity (1-3.8 A) on the EC-SF system performance. Moreover, the ANOVA results confirmed a satisfactory agreement between the experimental and predicted data for removal efficiency, energy consumption and flow rate of the process, with R² values of 0.96, 0.98, and 0.75, respectively. Notably, employing sand filtration as a post-treatment improved the flocculation efficiency (>90%) of destabilized nitrate ions through capturing unsaturated aluminum hydroxide particles within the sand media. The optimum conditions with an initial nitrate concentration of 187.2 mg/l, current intensity of 1.7 A, 100 minutes reaction time and pH 5 resulted in 93.52% nitrate elimination efficiency with a flow rate of 10 ml/min and energy consumption of 4.29 kWh/({text{m}}^{3}). However, the reduction in flow rate plateaued after 100 minutes, indicating the filter breakthrough threshold and the need for media replacement. Furthermore, sludge characterization confirmed the presence of ({text{Al}(text{OH})}_{3}) species, serving as the main coagulant for nitrate removal by adsorption on aluminum hydroxide flocs.

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With the aim of predicting potential nitrogen removal from waste wood products through pyrolysis, this paper presents development of generalized equations based on rigorous experimental measurements conducted earlier. Integrated parametric equations for three dependent variables related to nitrogen removal were developed based on two contributing factors: reaction time and temperature. Patterns of variations of dependent variables with independent variables were converted to parametric equations, which were eventually amalgamated to single equations having two independent variables. Three equations were developed for three dependent variables representing nitrogen removal; NH₃ release in mg, nitrogen elimination in percent and residual mass of wood in mg. Comparison of the developed equation produced results were assessed against original experimental data. Comparison revealed that the developed equation for NH₃ release is capable to accurately predict potential NH₃ release having a correlation coefficient of 0.99 with the experimental data. Standard statistical errors of the equation projected calculations are, RMSE = 0.13, MAE = 0.11 and RAE = 0.03. For the equations of nitrogen elimination and residual mass the achieved correlation coefficients were 0.94 and 0.97 respectively. Corresponding RMSE, MAE and RAE values are 2.51 & 21.72, 2.07 & 14.88 and 0.04 & 0.06 respectively. Such mathematical framework will be a useful tool for the stakeholders, who need to decide suitable input variables for a target nitrogen removal through the process of pyrolysis for wood waste.

The textile industry produces wastewater from synthetic dyes, such as Methylene Blue. This pollutant makes a significant contribution to global environmental pollution. A serious risk to human health and the aquatic ecosystem can occur from Methylene Blue toxicity and non-biodegradability. Titanium dioxide, well-known as a photocatalyst, offers a promising candidate for dye degradation under ultraviolet light due to its chemical stability and efficiency. However, the efficiency of Titanium dioxide can be limited by its wide band gap. To establish this, a Titanium dioxide /Polyaniline composite is expected to improve photocatalytic efficiency by reducing the band gap and enhancing light absorption. This study prepared a Titanium dioxide /Polyaniline composite through in situ polymerization, varying the mass of Titanium dioxide. The photocatalytic performance of these composites was evaluated by degrading methylene blue under Ultraviolet light. Characterization of Titanium dioxide/Polyaniline confirmed success based on X-ray diffraction, Fourier Transform Infrared Spectroscopy, and Scanning Electron Microscopy results. The composite reform has uniform dispersion and enhanced structural properties. The photocatalytic test confirmed that increasing the mass of The Titanium dioxide in the composite improves the degradation rate, nearly 100% for both low and high Methylene Blue concentrations within 180 min. The findings suggest that using the photocatalyst technique, Titanium dioxide /Polyaniline composites are a promising candidate for sustainable wastewater treatment.

This study presents an environmentally sustainable approach for synthesizing iron bionanoparticles using grape berries and grape pomace from two Vitis vinifera cultivars (Merlot and Blaufränkisch) highlighting the valorization of food industry waste within circular economy principles and the synergistic approach involving bacteria for environmental cleanup. The Merlot pomace-derived nanoparticles exhibited an amorphous structure, predominant Fe(III) species (Mössbauer spectroscopy), high specific surface area (398 m²·g⁻¹), and nanometric, porous morphology. Fe–O bond formation and polyphenol complexation was confirmed. Evolution of pH and redox potential values during synthesis revealed that slightly alkaline, near-physiological conditions favor nanoparticles formation and redox activity. All iron nanoparticle types were applied in removal experiments targeting polychlorinated biphenyls (from congener mixture Delor 103). The highest removal of the sum of PCBs congeners by nanoparticles alone reached 62% after 14 days using Merlot pomace-derived nanoparticles. When combined with the bacterium Ochrobactrum anthropi in a sequential synergistic approach, removal efficiency increased to 76%. Co-application with Stenotrophomonas maltophilia also resulted in high removal (70%). Ecotoxicological assessment revealed general non-toxicity of tested nanoparticles (derived from Merlot pomace) using Sinapis alba seed germination and Ochrobactrum anthropi auxanogram assays. However, higher concentrations (10 g·L⁻¹) induced 46% inhibition of plant growth, likely due to restricted translocation of nutrients to the upper plant tissues. The results demonstrate the dual benefit of transforming agrowaste into effective, low-toxicity nanomaterials for remediation, supporting sustainable nanotechnology for environmental applications.

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Separate waste collection is one of the key tasks of waste management. Improving economic efficiency and reducing the negative environmental impact of transportation is crucial for collection companies. This article presents the results of efficiency improvements in terms of reducing collection time, shortening collection vehicle routes, and reducing exhaust emissions. In addition, an evaluation of currently performed collections of separately collected waste based on real-life collections in rural areas and towns in southern Poland is included. Artificial intelligence algorithms—tabu search and ant colony algorithm—were used to optimize routes. Route optimization resulted in significant reductions in collection lead times, reducing collection times for currently completed routes from 4.3 to 13.1% and the route length from 17.2 to 31.3%. Optimization resulted in an average 22% reduction in NO_x, PM, and CO₂ emissions. The results are beneficial to waste collection companies that do not use artificial intelligence to improve routes and collection plans. Reduced collection duration following optimization may facilitate the alternating schedule of waste collections and include more collection locations every shift. The findings demonstrate economic advantages for waste collection companies and beneficial environmental effects for residents in the waste collecting zone, including reduced emissions. Additional multi-criteria analysis can assist in choosing the optimal options for route design, vehicle selection, and possible fleet replacement with electric trucks or alternative fuel vehicles.

Plastic waste, especially in micropollutant form, has become a critical global environmental issue. This study investigates the integration of polyethylene terephthalate (PET) into mycelium-based composites to isolate plastic waste from natural ecosystems. Four white-rot Ganoderma strains were evaluated for their PET-degrading capacity; and examined by SEM for colonization consistent with use of PET as the sole carbon source. The best-performing isolate (B8) was identified by ITS rDNA as Ganoderma cf. resinaceum; the sequence has been deposited in GenBank. This strain was applied to PET-containing composts composed of cardboard, coffee grounds, and rice husks to produce biocomposites via mycelial binding. Color change was quantified using L*a*b* values from three surface locations at baseline and 12 months, indicating a shift from whiter toward warmer tones. Preliminary compression observations indicated lower small-strain stiffness but higher high-strain strength with densification without disintegration relative to PET-free controls. Surface swab and passive air assessments indicated low microbial loads within the tested scope. The process encapsulates PET within the composite matrix, supporting upcycling rather than degradation. We present a distinct transformation pathway—upcycling-by-encapsulation—in which shredded PET is captured and immobilized within a mycelial matrix and repurposed as a structural filler rather than degraded or fragmented. Taken with the 12-month stability data, this performance profile supports an industrial-symbiosis pathway in which encapsulated PET can be circulated across sectors as a contained, value-retaining filler. Ganoderma-based mycelium fabrication offers a scalable and sustainable alternative for reintroducing PET waste into use while minimizing environmental exposure.

Electrocoagulation (EC) has emerged as a viable alternative for oily wastewater treatment, offering distinct advantages over conventional treatment methods. In EC, an electric current dissolves sacrificial anode, releasing metal ions that help clump and remove a wide range of contaminants. This technology is applicable across diverse industries and effectively addresses complex water challenges, including oil-contaminated wastewater. The efficiency of EC is influenced by operational parameters such as current density, electrode material, pH, electrode spacing, and treatment time, all of which require careful optimization. Notwithstanding its benefits, such as ease of operation, minimal chemical usage, and small sludge production, EC faces challenges related to electrode passivation and energy consumption, necessitating enhancement strategies. Given the growing interest in EC and the diversity of treatment conditions, a comprehensive synthesis of current knowledge is essential to guide both research and industrial applications. This review evaluates the principles and mechanisms of EC, the role of operational parameters, and strategies for process optimization. Recent innovations are highlighted, particularly hybrid systems that integrate EC with membrane filtration, advanced oxidation processes, and renewable energy sources. Applications across various wastewater types are discussed, alongside economic feasibility and scalability considerations. By identifying key research gaps, particularly in system scale-up, cost reduction, and long-term performance, this review provides a comprehensive resource to inform the future development of sustainable oily wastewater treatment technologies.

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Understanding regional vegetation carbon dynamics is vital for ecosystem carbon sequestration evaluation and climate mitigation planning. Focusing on Shanxi Province and its planned mining areas in China, this study investigated the dynamics and drivers of Net Ecosystem Productivity between 2001 and 2020 using soil heterotrophic respiration models, Sen+Mann–Kendall analysis, variation coefficients and Geodetector method. The results indicated that: From 2001 to 2020, Net Ecosystem Productivity in Shanxi Province demonstrated a spatial distribution with elevated levels in the southeast and diminished levels in the northwest. The vegetation collectively functioned as a carbon sink. The ranking of Net Ecosystem Productivity among the three major coal bases is as follows: Jindong>Jinzhong>Jinbei. The NEP in Shanxi Province demonstrated a steady ascent, registering a yearly increase of 7.25 (g C·m⁻²·a⁻¹). The trends in vegetation Net Ecosystem Productivity within the planned mining areas were generally consistent with those of Shanxi Province as a whole, while the Jinbei Base exhibited values significantly lower than the average for the planned mining areas. The areas showing an upward trend of Net Ecosystem Productivity comprised 91.81% of the study region. Precipitation, land utilization, and population density acted as the key determinants on the spatial layout of carbon sources and sinks. Compared with individual factors, the interactive effects of environmental and human-induced factors provided a more powerful explanation for Net Ecosystem Productivity.

The removal of manganese ions (Mn²⁺) from aqueous solutions using a strong acid cation-exchange resin, Purolite SST60, was investigated in the present study. The influences of resin dosage, temperature, and pH on Mn²⁺ removal were optimized using Response Surface Methodology based on a Central Composite Design. Results showed that removal efficiency was highly pH-dependent, increasing from 63% at pH 1.0 to over 99% at pH 3.0 and above. Even with only 0.01 g of resin, 98% removal was achieved, indicating high performance at low dosages. Equilibrium data aligned with the Langmuir isotherm, indicating monolayer sorption with a maximum capacity of 91.06 mg/g. Kinetic data followed a pseudo-second-order model. Thermodynamic analysis confirmed a spontaneous and exothermic process, supported by a negative enthalpy change and positive entropy change, likely due to dehydration of Mn²⁺ ions upon binding. Competitive ion studies revealed that divalent ions, particularly calcium and magnesium, significantly hinder Mn²⁺ removal, whereas monovalent ions had minimal impact. Complete desorption of Mn²⁺ was achieved using hydrochloric or nitric acid at concentrations of 0.5 mol/L and above, confirming the resin’s reusability. Overall, Purolite SST60 offers an efficient, regenerable, and robust solution for manganese removal in water treatment applications.

Ibuprofen is one of the most widely used analgesic and anti-inflammatory pharmaceuticals due to its availability and wide range of medical properties. High utilization is associated with the presence of the drug in aquatic ecosystems, raising concerns about potential environmental effects. This research assesses the influence of ibuprofen on the common aquatic macrophyte Lemna minor. The study was conducted for seven concentrations of ibuprofen: 5, 10, 20, 50, 100, 200 and 400 mg/L. The duration of the experiment was 21 days for the lower concentrations (5–20 mg/L) and 15 days for the higher concentrations (50–200 mg/L). To determine the toxicity of IBU, changes in weight gain, chlorophyll a and b content, and alterations in plant appearance were analyzed. Exposure to very high concentrations (≥ 100 mg/L) resulted in plant necrosis. Lower concentrations caused a significant reductions in fresh weight of 20% (5 mg/L), 36% (10 mg/L) and 16% (20 mg/L) after two weeks of exposure. Analysis of the results of the chlorophyll content of the plants showed a notable decrease in all IBU-treated groups as exposition time increased. Microscopic images showed signs of alterations suggesting the possibility of chlorosis and necrosis even under the low level of IBU. However, some results suggest that Lemna minor may show an adaptation to small amounts of IBU. These observations provide a basis for further research on the tolerance mechanisms and on the potential of Lemna minor for the phytoremediation of waters contaminated with pharmaceuticals.