Water Science and Technology最新文献

Metal-organic frameworks (MOFs) have garnered significant interest in the field of photocatalysis. In this study, Z-scheme heterojunction BM-x composites consisting of bismuth bromide oxide (BiOBr) and iron-based metal-organic backbone (MIL-100(Fe)) were successfully synthesized using ethylene glycol as a solvent. The composites were characterized using various techniques. BM-x exhibit abundant functional groups, large specific surface areas, and narrow band gap energy, thus provide numerous active sites for catalytic reactions and respond well to visible light. Notably, BM-7 displays remarkable catalytic activity in a visible light-activated permonosulfate (PMS) system and achieves a degradation rate of 99.02% over 100 mg/L gold orange II (AO7) within 60 min. The effects of BM-7 and PMS addition, initial AO7 concentration, initial pH, inorganic anions, and humic acid on the degradation system were investigated. The proposed mechanism of the Z-scheme heterojunction in the BM-7 photocatalyst demonstrates effective photoelectron transfer from the BiOBr conduction band to the MIL-100(Fe) valence band, resulting in excellent catalytic activity. Radical burst experiments identified ¹O₂, h⁺, and ·O₂^- as the main active substances. BM-7 has high stability and reusability, with a degradation rate reduction of only 14.48% after three recycles. These findings provide valuable insights into using persulfate combined with visible light.

This study aims to address a common issue in current research: the neglect of the calibrating model parameters when estimating evapotranspiration (ET) from green roofs (GRs) using the Priestley-Taylor model, with most studies limited to a single substrate depth (SD). To overcome this limitation, this research improves the accuracy of ET estimation for different SDs on GRs by calibrating the Priestley-Taylor coefficient α. The study period was 692 days in total, from 25 April 2021 to 26 April 2023. Daily ET data from the outdoor GR experimental group were used to calibrate and validate the model. Uncalibrated models perform well for medium SDs (150 mm) but decline for deeper (300 mm) or shallower (50 mm) ones. NSGA-II optimization significantly improved model performance across all SDs, notably at 300 mm. The research underscores the importance of parameter calibration for water management in GRs and sets a foundation for future research on optimizing water retention and regulation functions in GRs.

This work addresses the role of accurate input data in hydrological model simulations and explores the often-overlooked errors associated with evapotranspiration (ET). While existing literature primarily focuses on uncertainties in rainfall, this study underscores the necessity of considering errors in ET, as evidenced by some studies suggesting their substantial impact on hydrological model responses. A comprehensive exploration of uncertainty quantification resulting from errors in ET in hydrological model simulations is presented, highlighting the imperative to scrutinize this facet amidst diverse uncertainties. There are two approaches for addressing uncertainty in potential evapotranspiration (PET) inputs as discussed: directly considering uncertainty in PET data series or accounting for uncertainty in the parameters used for PET estimation. Furthermore, details are provided about the existing error models for PET measurements, revealing a limited number of studies that specifically account for ET-related uncertainties. Researchers commonly address ET errors by considering both systematic and random errors; some studies suggest that systematic errors in PET have a more substantial impact compared to random errors on hydrological model responses. In summary, the objective of this paper is to offer an in-depth exploration of uncertainty associated with PET inputs and their influence on hydrological modeling.

This paper presents the design of a web-based decision co-creation platform to showcase water treatment technologies connected via industrial symbiosis for a circular economy approach. The platform is developed as part of the EU H2020-funded ULTIMATE project. This system initially investigates three case studies focusing respectively on: water and nutrient recovery in greenhouses, pre-treatment of wastewater from olive mills before integration into communal wastewater systems, and value-added compound recovery from wastewater in a juice factory. These cases are then merged into one abstract composite example showing all three aspects of the problem, connecting greenhouses, juice factories, and olive mills, describing a pioneering form of industrial 'metabolic network' of the circular economy. This work describes the modelling framework, the online platform and the interactive visualisations that allow users to explore the industrial symbiosis configurations enabled by the metabolic pathway. The platform thus serves as a decision support tool that merges circular economy and industrial symbiosis, as well as a pedagogical tool.

This research aimed to investigate the influence of ferry operations and religious activities on the water quality of the Hooghly River in Kolkata, West Bengal, during 2022, while pinpointing pollution hotspots and suggesting mitigation strategies. As a crucial distributary, the Hooghly River is significantly impacted by human activities, particularly near ferry terminals and pilgrimage locations. Water samples (4 L) were taken from eight critical sites during pre- and post-monsoon periods at high tide, concentrating on important physico-chemical and biological attributes. Though pre-monsoon water quality largely adhered to BIS guidelines, heightened chemical oxygen demand and total coliform (TC) levels indicated potential pollution hotspots, likely caused by ferry movements and religious gatherings. Post-monsoon data revealed acceptable pH and temperature ranges but flagged concerns due to increased biochemical oxygen demand and TC counts, especially in high-traffic zones. The water quality index varied between 213 and 282, with a higher pre-monsoon value of 282 and a post-monsoon value of 213, primarily influenced by total dissolved solids, hardness, alkalinity, and conductivity. The comprehensive pollution index ranged from 1.30 to 1.33, surpassing the acceptable limit. These assessments reveal the impact of ferry and religious activities on the Hooghly River's water quality, stressing the need for targeted pollution control.

Human activities are intricately linked to entropy changes, inevitably impacting the ecological environment. The initial transportation of urban pipe network systems plays a critical role in this process. These systems involve processes such as fermentation, hydrogen production, acetic acid production, and methane production, generating gases, such as methane and carbon dioxide. Despite their importance, the mechanisms underlying entropy changes during organic matter degradation remain underexplored. This study establishes a 1,200-m-long urban sewer pilot system to analyze pollutant degradation through reaction equations. A novel method, based on standard molar reaction enthalpy changes, is developed to calculate entropy changes, revealing distinct stages of entropy increase. Results indicate that environmental entropy rises primarily during sugar degradation and acetic acid production, while entropy decreases during glucose degradation and methanogenesis. During sewage transport, the heat released from pollutant degradation exceeds that associated with greenhouse gas emissions, leading to a general increase in entropy in the external environment. The findings of this study could help to predict the actual influent quality of wastewater treatment plants and facilitate the optimization of wastewater treatment.

Dark fermentation has the potential to produce biohydrogen using raw material waste, such as wastewater from the corn industry (cornWW), which is characteristically alkaline and improperly discharged. This study aimed to assess the impact of different hydraulic retention times (HRT) on hydrogen production in a sequencing batch reactor system using raw cornWW as feedstock. Different HRTs were evaluated (4, 2, and 1 day(s)). Higher biohydrogen productivity was observed in HRT value of 1 day (893.6 ± 10.1 NmL H₂/L_reactor/day), indicating its favorable metabolic pathways leading to the generation of hydrogen, carbon dioxide, acetate, butyrate, and caproate. Microbial analysis revealed that the Atopobium and Clostridium (genera) played key roles in hydrogen and organic acid production. Additionally, during the fermentation of cornWW, lactic acid in the feedstock facilitated the production of caproic and propionic acids, further enriching the range of valuable byproducts obtained through this process.

Life cycle assessment (LCA), coupled with process modeling to develop the life cycle inventory, is a valuable tool to assess differences in environmental performance when evaluating alternatives based on sustainability (triple-bottom-line) principles. Coupled with a whole plant process model (SUMO21), an LCA assessed the environmental performance of options to upgrade biosolids management for the Great Lakes Water Authority water resource recovery facility. All five alternatives evaluated (composting plus four anaerobic digestion alternatives) were able to meet the core objectives of the biosolids management system upgrade: (1) address ageing incinerators, (2) minimize the mass of biosolids landfilled, and (3) reduce greenhouse gas emissions, compared to the existing (baseline) system. The mass of solids to be managed was reduced for the anaerobic digestion alternatives but not for the composting alternatives. Environmental impacts were reduced for the composting alternative for all six impact categories considered (global warming, eutrophication, carcinogenics, ecotoxicity, respiratory effects, and fossil fuel depletion) relative to the baseline, and further reduced for all four anaerobic digestion alternatives evaluated. The results allowed a phased implementation plan to be developed, which could be evaluated based on other factors, such as costs and operational factors.

Naphthenic acids are the most significant environmental pollutants created by the extraction of oil from oil sand deposits. Since the diffusion coefficient of naphthenic acid has a direct effect on the modeling of diffusion and advection and determining its behavior and movement in water, this number is needed for modeling work and future studies. In this study, the diffusion coefficient of this substance in water was determined experimentally and in a laboratory. The researchers used the device of the Armfield company, known as the device for determining the diffusion coefficient in liquids. In this research, after examining different methods of determining the concentration of naphthenic acid in the water, including UV-vis, chemical oxygen demand (COD), crystal violet, oxidation reduction potential, pH meter, and electrical conductivity meter, the COD method was the best method in determining the concentration at different times, which provided a suitable numerical range for the concentrations and a device was built for heavy oil pollutants with poor solubility in water to specify the diffusion coefficient, and for the first time, the diffusion coefficient of naphthenic acid in water was obtained with experiments and experimental equations as 0.69 × 10^-9 m²/s which indicates the weak diffusion of this substance in water.