Water Resources and Industry最新文献

A comparative study of the results obtained from using Fenton and electro-Fenton processes in textile wastewater treatment is presented. Global indicators, color, COD, TOC, and BOD₅ were employed to investigate the treatments. Examination of the representative by-products gave new insights into Fenton. Even though the color removal was higher for classical Fenton (almost 100% color removal) than for electro-Fenton, the overall purification effect was not directly advantageous for Fenton. We found that electro-Fenton removed COD and TOC more efficiently. The biodegradability BI (BOD₅/COD) parameter was investigated, where the textile wastewater was hardly biodegradable (BI was 0.12 ± 0.007). BI of Fenton was also low (0.044 ± 0.006). Electro-Fenton yielded a considerably more promising result, where BI was 0.83 ± 0.15, and proved more bio-friendly than classical Fenton. Additionally, electro-Fenton was more efficient in by-product removal, especially the naphthalic component, with 90% removal (while Fenton removed 50%). The by-products influenced the after-treatment toxicity assessment of V. fischeri. The EC₅₀ values were below 2% and even lower for electro-Fenton. The results of the color matching parameters (DE_CMC) of re-dyeing were unacceptable using after-Fenton water at 8.66. DE_CMC results were between 1.01 and 2.71 after electro-Fenton treatment and had a recycling perspective.

In the present study, to minimize water consumption and reduce wastewater production in an oil refinery, a technique called water pinch analysis (WPA) was used with two single and double pollutant approaches. Total dissolved solids (TDS) and chemical oxygen demand (COD) were selected as the index pollutants. The results showed that the use of WPA has reduced the overall consumption of freshwater in the refinery on average between 79 m³/h (45%) in the single pollutant approach (77 m³/h for COD and 81 m³/h for TDS) and 99 m³/h (56%) in the double pollutant approach. It was also found that the volume of produced oily and sanitary effluents decreased between 31 and 52 m³/h. These findings show that WPA is a useful tool that can help make strategic decisions to minimize water consumption and modify consumption patterns in industries, and by reducing effluent production environmental risks will be reduced.

Anomalous water-consumption events (AEs) can significantly impact the functioning of water distribution networks, and their prompt identification can improve the service provided by water utilities. This study proposes a new methodology for AE detection and pre-localization in water distribution networks relying exclusively on pressure-data collected in the field, which are exploited to evaluate differential-pressure trends for all possible pressure-sensors couples located in the WDN. In greater detail, AEs are detected and pre-localized by analysing differential-pressure trends over time. The level of deviation of these trends from the standard is considered to provide information about (i) AE alert levels and (ii) the area of the network where the AE is most likely to occur. The application of the methodology to two real case studies featuring different characteristics in terms of residential and industrial users demonstrated method effectiveness in detecting and pre-localizing individual and simultaneous AEs of different magnitude and occurring at different times of the day, providing useful information about the presence of AEs without the need for hydraulic models, and allowing the evaluation of their effects in terms of piezometric head alteration in the different areas of the system.

The efficacy of magnesium oxide (MgO)-bentonite clay nanocomposite particles (MgO nanoparticles embedded in powdered bentonite clay) for water and wastewater treatment applications is examined herein. Congo red (CR), a widely used azo dye, was used as the model contaminant. For CR concentrations ≤120 mg/L, the optimum nanocomposite dosage was ≤1 g/L, achieving CR removal ≥99% for contact times (mixing durations) ≤10 min, whereas temperature and pH had no significant effect on the treatment process. The removal of CR dye followed the pseudo-second-order model than the first order model. Furthermore, adsorption isotherms followed the Langmuir adsorption isotherm rather than the Freundlich adsorption isotherm (R² ≥ 0.99), hence confirming monolayer homogenous adsorption. The surface morphological and physicochemical characteristics of the nanocomposite were also identified, and results suggest that CR removal was governed by electrostatic attraction between the protonated hydroxyl groups (i.e., -OH²⁺), embedded on the nanocomposite surface, and the negatively charged –SO₃-groups of the CR dye. When used for the treatment of real printing ink wastewater, CR was practically removed (⁓100%), whereas for real printing and dyeing wastewater (PDW), a more challenging effluent that also contains salts and other contaminants, CR removal was ≥80%. Overall, the produced MgO-bentonite clay nanocomposite hold great promise for sustainable CR removal, a typical contaminant that is released by many industries including printing, tannery and textile, paper, plastic, and paint and coatings.

This study explores a new governance mechanism aimed at regional integration and explains how this mechanism can achieve optimal governance of water resources through the division of labour in politics and the economy. This study adopts political economic geography as the research approach. The data used in the analysis were obtained from official documents, interviews and field investigations, and its authenticity was interactively checked via triangulation. The results show that ‘spatial shifts’ were the driving force behind water redistribution. The division of labour between politics and the economy eliminates obstacles to water distribution through the mutual adjustment and division of underground rhizomes; ‘creative destruction’ and ‘destructive creation’ are alternately used to achieve dialectical progress. This study concludes that in this case, the process of regional integration simultaneously generates circular mechanisms in which political power and economic productivity are consolidated.

New catalyst synthesis techniques, including green materials, are extensively studied for heterogeneous photocatalytic advanced oxidation processes (AOPs) on spotlight of sustainable development. Deep eutectic solvents (DESs) started to be used in this field as environmentally friendly alternative to ionic liquids (ILs).

During the catalyst synthesis, DESs can act as stabilizers, capping agents, structure directing agents, templates, hydrolyzing agents, etching agents, intercalators, and latent supramolecular catalysts. Importantly, DESs have exhibited the ability to significantly influence catalyst morphology, functionalization and photocatalytic properties (confirmed both for classic UV lamps and light emitting diode (LED)), including band-gap modification.

DESs positive effect was proved for a variety of materials, including metal oxides, metalorganic (MO) complexes and doped materials, MXene (MAX phase etching in DES environment), inorganic-organic hybrids, carbo-catalysts. Substantial enhancements were obtained for modification of photocatalytic materials like TiO₂, ZnO, MnO₂, iron oxides, ceria oxides, CdS, bismuth based photocatalysts and biochar modification. In this aspect, a particular role of DESs was confirmed for synthesis of nanomaterials in a form of nanoparticles, nanopowders or nanosheets.

Effectiveness was further increased by oxidants such as hydrogen peroxide, persulfates and Fenton process. Effective application of DES-modified catalysts was confirmed for degradation of dyes (Rhodamine B, Reactive orange 16, Safranine, Orange II, methylene blue), pharmaceuticals and antibiotics (Cefixime, Tetracycline, Oxytetracycline, Flumequine, Sulfamethaxazole), PFASs (Perfluorooctanoic acid) and Cr(VI). This reveals high potential of DES based photocatalysts for environmental engineering and remediation.

There are still remaining a significant gaps in our understanding of the roles and impacts of DESs in AOPs. Furthermore, there is an absence of data regarding the recovery of DESs in the catalyst synthesis processes applied in AOPs. Addressing this aspects is vital for economic and environmentally friendly applications. As research progresses, it is essential to unravel the intricacies of DES-mediated catalyst synthesis and their broader consequences.

Hidden collapse column associated with high pressure dynamic water is a main cause of major water inrush accidents in North China type coal fields. Taking the structural abnormality area discovered in 11603 working face of Daizhuang Coal Mine as an example, underground three-dimensional high-density electrical method, advanced exploration of underground drilling and curtain grouting were used to detect the existence of collapse column, and analyzed the water conductivity of collapse columns based on the hydraulic connection analysis of the 13th limestone and Ordovician limestone aquifers. Finally, it is determined that this abnormal area is a strong water filling collapse column originating from the upper Ordovician strata runoff zone (inferred to be within a range of 30 to 100 m below the Ordovician limestone top interface), developed to a height of 12th limestone. Based on the fact that the water yield and water pressure of underground directional drilling, the grouting pressure of curtain grouting, and the amount of cement injected are external quantitative factors that reflect the existence of hidden karst collapse columns during the process of detecting hidden karst collapse columns, and in combination with the feature that deep learning can fully independently learn abstract knowledge expression, a prediction model based on convolutional neural networks is constructed. According to the established network model, it was found that among the 12 sets of actual measurement data, only one data point indicated the absence of a collapse column. The prediction accuracy reached 91.6%, which meets the practical needs.

Bangladesh holds the 2nd position after China in the global apparel market in terms of denim export. In the textile industry clusters of Bangladesh, the groundwater level is depleting at an alarming rate due to overconsumption and mismanagement. The present study evaluates the groundwater conservation potential of a denim facility in Manikganj District through an effluent recycling and reuse approach. In this study, 100% treated wastewater and 10% treated wastewater mixed with softwater were utilized in the wet processing plant to dye and wash sample denim products and investigated for their fabric quality using seven parameters. The test results followed the requirements given by the North American and European fashion brands that source denim products from Bangladesh. The feasibility assessment of groundwater conservation through its high (100%) and low (10%) recycling rates indicated that the studied facility can potentially save around 619,230 m³ and 61,923 m³ of groundwater in a year, respectively.

A novel p–n heterojunctions composite of BiBaO₃ and Ag₃PO₄ were synthesized to significantly enhance the degradation efficiency of antibiotic wastewater. Through compositional analysis, micron-sized BiBaO₃ particles were combined with nano-sized Ag₃PO₄ particles, resulting in a composite (Ag/0.75Bi) with excellent visible light absorption properties. Moreover, the photocatalytic efficiency was evaluated for Tetracycline and Oxytetracycline degradation, demonstrating remarkable degradation efficiencies. Under visible light irradiation, pollutants were degraded almost completely within 40 min, while the composite photocatalysts exhibited acceptable stability. The photocatalyst mechanism was investigated by conducting photoelectric effect, free radical capturing, and detection experiments. The p-type BiBaO₃ and n-type Ag₃PO₄ compound facilitated the transfer of photogenerated electrons and holes, reducing their recombination probability and improving photocatalytic efficiencies. Furthermore, hydroxyl and superoxide radicals played a crucial role in the photodegradation of pollutants. Overall, this study provides novel insights into the development of composite catalyst for the photocatalytic degradation of antibiotic wastewater.

Sulphurous water is used for balneotherapeutic purposes throughout the world. Its therapeutic properties are affected by the forms and concentrations of S(II) occurring in the solution. The processes that occur along the flow of water can affect the speciation of sulphur and influence on the installation. This article concerns an investigation of hydrogeochemical processes in five different sulphurous water distribution systems. Speciation modelling indicated that, in cold water, the concentration of H₂S equals or even exceeds that of HS⁻. In hot water, bisulfides become the predominant form and constitute 60–70 %. Natural waters usually achieve equilibrium with carbonate minerals, while upon heating, the water tends to become supersaturated with respect to these minerals. The calculated LSI values exceed 0.5 indicating a propensity for scale formation. Also, RSI values suggest that a scale formation is possible in the systems. No significant differences in the concentration of S(II) compounds are observed at various points.