Water science and engineering最新文献

{"title":"Enhanced total nitrogen removal and membrane fouling control by increasing biomass in MBR equipped with ceramic membrane","authors":"","doi":"10.1016/j.wse.2024.01.001","DOIUrl":"10.1016/j.wse.2024.01.001","url":null,"abstract":"<div><div>Simultaneous nitrification and denitrification (SND) is an efficient method to remove nitrogen in municipal wastewater treatment. However, low dissolved oxygen (DO) concentrations are generally required, leading to serious membrane fouling in membrane bioreactors (MBRs). This study aimed to clarify the synergistic effect of biomass and DO on nitrogen removal and membrane fouling. To achieve this goal, four submerged MBRs equipped with ceramic membranes were operated with different biomass (mixed liquor suspended solids (MLSS)) concentrations (3 000 mg/L, 5 000 mg/L, 7 500 mg/L, and 12 000 mg/L) under various DO concentrations (2.0 mg/L, 1.0 mg/L, and 0.5 mg/L). As a result, increasing biomass in the MBRs enhanced total nitrogen (TN) removal via SND, and excellent TN removal efficiencies of 60.7% and 75.8% were obtained using the MBR with an MLSS concentration of 12 000 mg/L and DO concentrations of 2.0 mg/L and 1.0 mg/L. However, a further decrease in DO deteriorated TN removal due to the inhibition of nitrification. Moreover, high MLSS concentrations were beneficial to membrane fouling control for ceramic membranes in MBRs. The lowest transmembrane pressure development rate was observed for the MBR with an MLSS concentration of 12 000 mg/L. High biomass offset the adverse effect of DO decrease on membrane fouling to some extent, and improved the stability of the reactor. Therefore, biomass might be an important parameter for membrane fouling reduction in ceramic MBRs. Overall, optimal biomass and DO concentrations for TN removal were identified, providing useful information for the successful operation of MBRs with efficient TN removal and membrane fouling control.</div></div>","PeriodicalId":23628,"journal":{"name":"Water science and engineering","volume":"17 4","pages":"Pages 352-360"},"PeriodicalIF":3.7,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139395719","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Perspectives on risk analysis and control for real-time operation of flood control systems","authors":"Juan Chen ,&nbsp;Lu Zhang ,&nbsp;Guo-zhi Li ,&nbsp;Ping-an Zhong","doi":"10.1016/j.wse.2024.06.002","DOIUrl":"10.1016/j.wse.2024.06.002","url":null,"abstract":"<div><div>Flood control operation, a non-engineering measure, can efficiently manage flood disasters within a river basin. However, numerous uncertainties exit in the real-time operation of flood control systems, creating risks in decision-making. As an efficient tool to mitigate these risks, risk management has garnered increasing attention in real-time flood control operation. This communication offers a series of suggestions for future research concerning risk management in real-time flood control operation, including risk assessment, risk diagnosis, and risk control methods.</div></div>","PeriodicalId":23628,"journal":{"name":"Water science and engineering","volume":"17 4","pages":"Pages 319-322"},"PeriodicalIF":3.7,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142535575","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of geometric features of impermeable discrete bedform on hyporheic exchange","authors":"","doi":"10.1016/j.wse.2024.01.003","DOIUrl":"10.1016/j.wse.2024.01.003","url":null,"abstract":"<div><div>The bedform-driven hyporheic exchange plays a crucial role in mass transport within natural aquatic ecosystems like streams and rivers. This study aimed to unveil the impact of geometric features of impermeable discrete bedforms on hyporheic exchange by experimentally measuring quantitative hyporheic exchange flux data and variation characteristics in an annual flume. The experiments encompassed diverse conditions involving the ratio of bedform wavelength (<em>λ</em>) to wave height (<em>h</em>) and relative submergence. The study also analyzed the dependence of the effective diffusion coefficient on the geometric characteristics of bedform composition elements. The experimental results showed that, in comparison to a permeable flat bed, the presence of an impermeable discrete bedform tended to either attenuate or enhance hyporheic exchange, contingent on the geometric characteristics of bedform composition elements. The hyporheic exchange flux exhibited an initially increase followed by a decrease with increasing <em>λ</em>/<em>h</em>, with turbulence penetration emerging as the dominant mechanism governing hyporheic exchange for cases with relatively denser bedform composition elements (e.g., <em>λ</em>/<em>h</em> = 4.0). The effective diffusion coefficient peaked at <em>λ</em>/<em>h</em> around 6.0–8.0, owing to a significant augmentation in the relative contribution of pumping exchange to gross hyporheic exchange. Furthermore, the hyporheic exchange intensity generally increased with decreasing relative submergence, primarily attributed to the augmented relative contribution of pumping exchange to gross hyporheic exchange.</div></div>","PeriodicalId":23628,"journal":{"name":"Water science and engineering","volume":"17 4","pages":"Pages 388-396"},"PeriodicalIF":3.7,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139632532","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Preparation and application of Ag–Ce–O composite metal oxide catalyst in catalytic ozonation for elimination of Reactive Black 5 dye from aqueous media","authors":"Nikita P. Chokshi,&nbsp;Abhi Chauhan,&nbsp;Rahul Chhayani,&nbsp;Sandip Sharma,&nbsp;Jayesh P. Ruparelia","doi":"10.1016/j.wse.2023.08.005","DOIUrl":"10.1016/j.wse.2023.08.005","url":null,"abstract":"<div><p>It is necessary to treat textile effluents before discharging them into natural water bodies as they harm the environment. Compared to conventional treatment methods, catalytic ozonation has gained attention due to its effectiveness in removing refractory organic pollutants. In this study, the coprecipitation method was used to synthesize a composite metal oxide of silver and cerium oxide, and the synthesized catalyst was used to eliminate the Reactive Black 5 (RB5) dye. X-ray diffraction, scanning electron microscopic, and Brunauer–Emmett–Teller surface area analyses were performed to characterize the synthesized catalyst. Afterwards, relevant experimental parameters, such as pH, ozone and catalyst dosages, and initial dye concentration, were investigated. The experiments revealed that the optimal experimental conditions were a pH value of 10, a catalyst dosage of 0.7 g/L, and an ozone dosage of 60 L/h. In these optimized conditions, the RB5 dye was entirely removed, and a chemical oxygen demand removal efficiency of 88% was achieved within a reaction time of 80 min. Furthermore, the recycling potential of the catalyst was tested for three cycles, and no deterioration in its activity was observed. Additionally, studies were conducted using a hydroxyl radical scavenger in order to understand the reaction pathway of the system. As a result, the indirect pathway was more dominant than the direct pathway in the system.</p></div>","PeriodicalId":23628,"journal":{"name":"Water science and engineering","volume":"17 3","pages":"Pages 257-265"},"PeriodicalIF":4.0,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1674237023000832/pdfft?md5=4e3d981aca9029f136ebff783e53cab1&pid=1-s2.0-S1674237023000832-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48904501","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hydrological responses to permafrost degradation on Tibetan Plateau under changing climate","authors":"Xue-gao Chen ,&nbsp;Zhong-bo Yu ,&nbsp;Hui Lin ,&nbsp;Tong-qing Shen ,&nbsp;Peng Jiang","doi":"10.1016/j.wse.2024.04.002","DOIUrl":"10.1016/j.wse.2024.04.002","url":null,"abstract":"<div><p>The Tibetan Plateau (TP) has undergone significant warming and humidification in recent years, resulting in rapid permafrost degradation and spatiotemporal variations in hydrological processes, such as subsurface water transport, hydrothermal conversion, and runoff generation. Understanding the mechanisms of hydrological processes in permafrost areas under changing climate is crucial for accurately evaluating hydrological responses on the TP. This study comprehensively discusses the permafrost hydrological processes of the TP under changing climate. Topics include climate conditions and permafrost states, subsurface water transport under freeze–thaw conditions, development of thermokarst lakes and hydrothermal processes, and runoff response during permafrost degradation. This study offers a comprehensive understanding of permafrost changes and their hydrological responses, contributing significantly to water security and sustainable development on the TP.</p></div>","PeriodicalId":23628,"journal":{"name":"Water science and engineering","volume":"17 3","pages":"Pages 209-216"},"PeriodicalIF":4.0,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1674237024000486/pdfft?md5=694ccebde1609b67f2443ffe39038146&pid=1-s2.0-S1674237024000486-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140779406","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biogas and photovoltaic solar energy as renewable energy in wastewater treatment plants: A focus on energy recovery and greenhouse gas emission mitigation","authors":"Sevda Jalali Milani,&nbsp;Gholamreza Nabi Bidhendi","doi":"10.1016/j.wse.2023.11.003","DOIUrl":"10.1016/j.wse.2023.11.003","url":null,"abstract":"<div><p>Globalization has led to a rapid rise in energy consumption, making climate change one of the world's most pressing issues. As wastewater treatment plants (WWTPs) contribute to climate change by emitting greenhouse gases (GHGs), this study estimated the total GHG emissions of WWTPs by classifying them as either direct or indirect carbon emissions. The effectiveness of the use of solar photovoltaic systems and biogas produced by WWTPs in increasing energy recovery and reducing GHG emissions was investigated. This study demonstrated that the use of an up-flow anaerobic sludge blanket (UASB) reactor with a biogas flow of 9 120.77 m³/d and an activated sludge processing system (ASPS) reactor with a biogas flow of 14 004 m³/d, in addition to the energy production from the UASB reactor (6 421.8 MW⸱h per year) and the ASPS reactor (9 860.0 MW⸱h per year), yielded a reduction of 3 316.85 and 5 092.69 t of CO₂ equivalent per year, respectively. Furthermore, the co-design of wastewater processes could be utilized to optimize biogas energy recovery. Moreover, the use of solar photovoltaic systems reduced GHG emissions from WWTPs. This is important to the transition to renewable energy because it resulted in a 10%–40% reduction in carbon emissions from WWTPs. Integrating renewable energy sources, biogas, and solar energy could provide up to 88% of the annual energy requirements of WWTPs. Recommendations are provided for further research considering the limited availability of integrated resources for studying the simultaneous utilization of photovoltaic and biogas systems.</p></div>","PeriodicalId":23628,"journal":{"name":"Water science and engineering","volume":"17 3","pages":"Pages 283-291"},"PeriodicalIF":4.0,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S167423702300114X/pdfft?md5=d6a75ed56c58ecbb4102973c36f262a7&pid=1-s2.0-S167423702300114X-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139297627","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of aeration on low-substrate CANON process","authors":"Qiong-qiong Xia,&nbsp;Wei Shang,&nbsp;Xing-can Zheng,&nbsp;Wen-an Zhang,&nbsp;Ya-xiong Wang,&nbsp;Yong-li Sun,&nbsp;Peng-feng Li","doi":"10.1016/j.wse.2023.11.005","DOIUrl":"10.1016/j.wse.2023.11.005","url":null,"abstract":"<div><p>The completely autotrophic nitrogen removal over nitrite (CANON) is a new type of nitrogen removal process developed in recent years. The control of dissolved oxygen (DO) in this process is relatively stringent, especially in low-substrate wastewater treatment. However, the results of studies on the operation of the process in different aeration modes are still controversial, and investigations on biofilm type CANON reactors are limited. In this study, a pilot-scale CANON bioreactor filled with suspended carriers was investigated on the treatment of wastewater at low ammonium concentrations, and the effect of the aeration mode on autotrophic nitrogen removal was evaluated. Seven conditions with various aeration on/off times and DO levels were tested. The results showed that an intermittent aeration with a 20-min/20-min aeration on/off time and DO concentrations of 1.0–1.3 mg/L at the end of the aeration period was appropriate, potentially inhibiting nitrite oxidizing bacteria (NOB) and keeping the total nitrogen (TN) removal rate at a relatively high level of 76.7% ± 2.5%. In the optimal aeration mode, the reactor achieved effluent TN and <span><math><msubsup><mtext>NH</mtext><mn>4</mn><mo>+</mo></msubsup><mtext>-</mtext><mi>N</mi></math></span> concentrations of (11.1 ± 3.3) mg/L and (3.6 ± 2.3) mg/L, respectively, with a hydraulic retention time of 12 h and an influent <span><math><msubsup><mtext>NH</mtext><mn>4</mn><mo>+</mo></msubsup><mtext>-</mtext><mi>N</mi></math></span> concentration of (48.6 ± 9.4) mg/L at 30.1°C ± 2.2°C. The results of metagenomic sequencing for microorganisms on carriers indicated that the main nitrogen removal bacteria in the reactor were Proteobacteria, Planctomycetes, and Nitrospirae. The NOB genus <em>Nitrospira</em> was completely inhibited by intermittent aeration. <em>Candidatus Kuenenia</em> had strong adaptability to low-concentration wastewater.</p></div>","PeriodicalId":23628,"journal":{"name":"Water science and engineering","volume":"17 3","pages":"Pages 292-299"},"PeriodicalIF":4.0,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1674237023001163/pdfft?md5=9279a43348416861ef64f9c92d14a4d7&pid=1-s2.0-S1674237023001163-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139295331","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microbial community diversity during algal inhibition using slow-release microcapsules of tea polyphenols","authors":"Li-xiao Ni ,&nbsp;Yuan-yi Fang ,&nbsp;Cun-hao Du ,&nbsp;Jia-jia Wang ,&nbsp;Cheng-jie Zhu ,&nbsp;Chu Xu ,&nbsp;Shi-yin Li ,&nbsp;Jian Xu ,&nbsp;Xu-qing Chen ,&nbsp;Hua Su","doi":"10.1016/j.wse.2024.05.004","DOIUrl":"10.1016/j.wse.2024.05.004","url":null,"abstract":"<div><p>Harmful algal blooms (HABs) resulting from eutrophication pose a major threat to ecosystems and human health, necessitating effective control measures. Allelochemicals have shown their importance in slowing down algal proliferation due to their proven efficacy and low ecological impacts. In this study, allelopathy tea polyphenols (TPs) and β-cyclodextrin were combined to prepare slow-release algicidal microcapsules, and the diversity of microbial community in the algal inhibition process was analyzed. Results showed that TP slow-release microcapsules had strong algicidal activity. When against <em>Microcystis aeruginosa</em> within 20 d, their constant inhibitory rate was up to 99% compared to the control group. Microbial diversity decreased with an increase in algae density, and the species richness and diversity of algae increased under the stress of TP slow-release microcapsules. The redundancy analysis showed that the environmental factors with impacts on the abundance and diversity of bacterial communities in descending order were dissolved oxygen, pH, and temperature. This study provides a theoretical basis for the application of TP slow-release microcapsules to actual water.</p></div>","PeriodicalId":23628,"journal":{"name":"Water science and engineering","volume":"17 3","pages":"Pages 266-273"},"PeriodicalIF":4.0,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1674237024000528/pdfft?md5=10c451ad88403e633f575865288f70e8&pid=1-s2.0-S1674237024000528-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141133382","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Numerical modeling of a mooring line system for an offshore floating wind turbine in Vietnamese sea conditions using nonlinear materials","authors":"Hien Hau Pham","doi":"10.1016/j.wse.2023.10.004","DOIUrl":"10.1016/j.wse.2023.10.004","url":null,"abstract":"<div><p>The offshore renewable energy industry has been developing farms of floating offshore wind turbines in water depths up to 100 m. In Vietnam, floating offshore wind turbines have been developed to increase the production of clean and sustainable energy. The mooring system, which is used to keep the turbine stable and ensure the safety and economic efficiency of wind power production, is an important part of a floating offshore wind turbine. Appropriate selection of the mooring type and mooring line material can reduce the risks arising from the motion of wind turbines. Different types of mooring line material have been simulated and compared in order to determine the optimal type with the minimum motion risk for a floating wind turbine. This study focused on numerical modeling of semi-taut mooring systems using nonlinear materials for a semi-submersible wind turbine. Several modeling approaches common to current practice were applied. Hydrodynamic analysis was performed to investigate the motion of the response amplitude operators of the floating wind turbine. Dynamic analysis of mooring systems was performed using a time domain to obtain the tension responses of mooring lines under the ultimate limit states and fatigue limit states in Vietnamese sea conditions. The results showed that the use of nonlinear materials (polyester and/or nylon) for mooring systems can minimize the movement of the turbine and save costs. The use of synthetic fibers can reduce the maximum tension in mooring lines and the length of mooring lines. However, synthetic fiber ropes showed highly nonlinear load elongation properties, which were difficult to simulate using numerical software. The comparison of the characteristics of polyester and nylon mooring lines showed that the maximum and mean tensions of the nylon line were less than those of the polyester line. In addition, the un-stretched length of the polyester line was greater than that of the nylon line under the same mean tension load. Therefore, nylon material is recommended for the mooring lines of a floating offshore wind turbine.</p></div>","PeriodicalId":23628,"journal":{"name":"Water science and engineering","volume":"17 3","pages":"Pages 300-308"},"PeriodicalIF":4.0,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1674237023000960/pdfft?md5=75bbc004fb333f8d976fcfe2943d3936&pid=1-s2.0-S1674237023000960-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"136129767","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prediction of wetting pattern dimensions under moistube irrigation with a multivariate nonlinear model","authors":"Yan-wei Fan,&nbsp;Chong Ren,&nbsp;Zhi-wei Yang,&nbsp;Chang-yan Zhang,&nbsp;Wei-fan Yin","doi":"10.1016/j.wse.2023.12.006","DOIUrl":"10.1016/j.wse.2023.12.006","url":null,"abstract":"<div><p>Moistube irrigation is a new micro-irrigation technology. Accurately estimating its wetting pattern dimensions presents a challenge. Therefore, it is necessary to develop models for efficient assessment of the wetting transport pattern in order to design a cost-effective moistube irrigation system. To achieve this goal, this study developed a multivariate nonlinear regression model and compared it with a dimensional model. HYDRUS-2D was used to perform numerical simulations of 56 irrigation scenarios with different factors. The experiments showed that the shape of the wetting soil body approximated a cylinder and was mainly affected by soil texture, pressure head, and matric potential. A multivariate nonlinear model using a power function relationship between wetting size and irrigation time was developed, with a determination coefficient greater than 0.99. The model was validated for cases with six soil texture types, with mean average absolute errors of 0.43–0.90 cm, root mean square errors of 0.51–0.95 cm, and mean deviation percentage values of 3.23%–6.27%. The multivariate nonlinear regression model outperformed the dimensional model. It can therefore provide a scientific foundation for the development of moistube irrigation systems.</p></div>","PeriodicalId":23628,"journal":{"name":"Water science and engineering","volume":"17 3","pages":"Pages 217-225"},"PeriodicalIF":4.0,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S1674237023001254/pdfft?md5=c011fde7945cf2bcb410cdef7e4bcac0&pid=1-s2.0-S1674237023001254-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139187906","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}