ALBERT

Beschreibung: Water treatment specialists need more and more to understand how viruses behave in potable water pipes and wastewater setups. This work discusses the late advances in dealing with viruses present in water treatment processes. Activated carbon adsorption (ACA) remains one of the most efficient and credible physicochemical methods. Nanoparticles have been utilized to turn activated carbon into a more efficient sorbent. Membrane filtration could lead to total elimination of viruses and ensure the safety of drinking water plants. As a feasible utilization for disinfecting potable water, solar disinfection (SODIS) remains a green and cost-efficient technology with its optical and thermal pathways and deserves more interest in its large and industrial implementation. Identically, solar distillation remains a viable solution for disinfecting and treating water. The water treatment techniques that are currently utilized for surface water treatment are appropriate for eliminating viruses like influenza A viruses, as proved by the literature. More strict precautions have to be taken to secure viruses' total elimination from water and wastewater as for influenza A and H5N1 in terms of advanced oxidation processes, ACA, and membrane processes application. Before reaching surface water, pathogens have to be removed efficiently from hospital and municipal wastewaters.

Beschreibung: A renewable, green activated carbon made from sucrose (sugar) was compared with traditional bituminous coal-based granular activated carbon (GAC). Single and multi-component competitive adsorption of nitrate and phosphate from water was investigated. Langmuir and Freundlich isotherm models were fitted to data obtained from the nitrate and phosphate adsorption experiments. Nitrate adsorption fits closely to either Freundlich or Langmuir model for sucrose activated carbon (SAC) and GAC with a Langmuir adsorption capacity of 7.98 and 6.38 mg/g, respectively. However, phosphate adsorption on SAC and GAC demonstrated a selective fit with the Langmuir model with an adsorption capacity of 1.71 and 2.07 mg/g, respectively. Kinetic analysis demonstrated that adsorption of nitrate and phosphate follow pseudo-second-order kinetics with rate constant values of 0.061 and 0.063 g/(mg h), respectively. Competitive studies between nitrate and phosphate were demonstrated in preferential nitrate removal with GAC and preferential phosphate removal with SAC. Furthermore, nitrate and phosphate removals decreased from 75% removal to 35% removal when subject to multi-component solutions, which highlights the need for adsorption analysis in complex systems. Overall, SAC proved to be competitive with GAC in the removal of inorganic contaminants and may represent a green alternative to coal-based activated carbon.

Beschreibung: Two laboratory-scale single-stage submerged membrane bioreactors (MBRs) were operated in parallel to examine the effect of different flux conditions and several fouling mitigation methods. After control operation (filtration only), three fouling control methods (relaxation, standard backwash and chemical backwash) at 27 litres per m2 per hour (LMH) flux and four different flux conditions (54, 36, 27 and 18 LMH) with standard backwash were applied. Physical performance of MBRs was evaluated based on the operational duration to reach maximum transmembrane pressure and the volume of permeate produced during the operational duration. Then relative cost–benefit analysis was carried out. Results showed that the combination of chemical backwash and standard backwash was the most effective for fouling mitigation in terms of physical improvement of MBR performance. However, the combination proved less economical (400% + α relative cost) than standard backwash alone (343% relative cost), because of the additional cost for pumps and chemicals. It also showed that lower flux (18 LMH) is desirable as it showed better physical performance (1,770% improvement as compared to the highest flux, 54 LMH) and proved more economical than higher flux configuration. Therefore, it is concluded that the operation with standard backwash at the lowest possible flux is the best combination to improve MBR performance as well as long-term cost–benefit.

Beschreibung: The expansion of water-intensive industrial activities and the impacts of climate change are jeopardising the sufficiency of safe drinking water in several Southeast Asian countries. One is Viet Nam, where geogenic arsenic contamination further limits the availability of freshwater resources with a simultaneous increase in water demand. Innovative and sustainable water treatment technologies are required to meet these challenges. Equally, we assume that the provision of safe drinking water requires tailored business models (BMs). In this study, we focus on the key stakeholders and framework conditions to design tailored BMs providing safe drinking water to the low-income and middle-income population in Viet Nam. We consider decentralised technologies to be suitable due to their lower investment costs for implementation and the avoidance of strong path dependencies. We therefore conducted a literature review and interviews with international experts in the domain of decentralised water treatment technologies. Our results show that relevant aspects include a lack of financial resources, specific characteristics associated with Vietnamese culture, e.g. the importance of relationships and trust in the business domain, lack of education and vocational training, market saturation suggesting co-operation with existing water suppliers, lack of suitable partners, and deficiencies in the institutional environment.

Beschreibung: Waste stabilization ponds (WSP) are a well-established wastewater treatment technology in Namibia. However, they are often overloaded and we still lack concepts and technologies for improvement. Therefore, this study presents the full-scale implementation of two pretreatment technologies to reduce the inflow of organic and solid loads into a facultative pond. We specifically compared the effects of anaerobic biological and mechanical pretreatment by an upstream anaerobic sludge blanket (UASB) reactor and a 250 μm micro sieve (MS). Not only in Namibia but also in most sub-Saharan countries, there is little experience with these technologies for the treatment of municipal wastewater in small and fast-growing local communities. Both technologies were tested in parallel for a period of 17 months and proved operational. While the UASB achieved better removal results with respect to chemical oxygen demand (COD) and suspended solids (TSS), the MS was more flexible in handling changing inflow patterns and had a much smaller footprint. The average total COD reductions of the MS and the UASB were 22 and 50%, respectively. TSS were removed by 45% with the MS and by 57% with the UASB reactor. Therefore, UASB and MS are viable options for the enhancement of existing WSP to reach better effluent values of the facultative pond.

Beschreibung: Urban areas are complex, vulnerable and continuously evolving, with interacting strategic services, assets and stakeholders. Potential effects of climate dynamics on urban areas may include the aggravation of current conditions, with identification of new hazards or risk drivers. These challenges require an integrated and forward-looking approach to sustainable urban development. Several tools and frameworks for assessing resilience have already been developed in different fields of study. However, aiming to focus on climate change, urban services and infrastructure, some specific needs were identified. In this light, a resilience assessment framework was developed to direct and facilitate an objective-driven resilience diagnosis of urban cities and services; to support decisions on selection of resilience measures and development of strategies to enhance resilience to climate change; to outline a path to co-build resilience action plans; and to track the progress of resilience in the city or in the service over time. The paper presents an outline of the structure of the framework and details the approach used in its development, including engagement tools and actions undertaken to assure stakeholder involvement in its development, validation and testing.

Beschreibung: High-temperature calcination was used to modify garnet media. Brunauer–Emmett–Teller (BET) measurements, X-ray diffractometer (XRD), scanning electron microscopy (SEM), zeta potential analysis, and a static adsorption experiment on humic acid removal were carried out to compare unmodified garnet and traditional quartz sand. Fitting adsorption isotherm of the media before and after modification was conducted to determine the adsorption type, and a dynamic filtration experiment was performed to treat micro-polluted water. Results of the characterization analysis and the static adsorption experiment revealed that, compared with the smooth surface of unmodified garnet, the surface of modified garnet media was covered with Fe2O3, which showed a rough concave-convex structure with a specific area that was 2.44 times larger than that of unmodified garnet. The removal efficiency of organic matter after modification increased from 2.5–4.5% to 51.7–63.1%, and the adsorption capacity increased 11–24 times. The adsorption type of the modified garnet media belongs to the Langmuir and Freundlich adsorption mode, while that of the original media belongs to the Freundlich adsorption mode. Results of the dynamic filtration experiment revealed that the effect of modified garnet media on turbidity, CODMn, and UV254 removal was better than that of unmodified garnet and traditional quartz sand.

Beschreibung: Approximately 40% of the water used in intensive agriculture is discarded as ‘drainage,’ which contains high amounts of ions that pollute the environment. This work aimed at investigating polyculture (tomatoes, cucumbers, and lettuce) under three production systems, namely, open (OPS), soil (SPS), and closed (CPS), in which the drainage water from the first crop was used to feed the second crop, and the water from the second crop was used to feed the third crop. The water and fertilizer efficiencies and some physical–chemical properties of the plants and soil were measured. The results showed no significant difference in the yield for polycultures between the CPS and OPS systems. The most efficient system for water use was the CPS, with 54.85 kg m−3, with a water savings of 55.69% compared to the OPS. The efficiency of fertilizers, such as N, P, K, Ca, and Mg, was statistically higher in the CPS, providing more kilograms of fruit per kilogram of nutrients. The reuse of drainage water in a polyculture not only increased the efficiency of the water and fertilizers but also increased the yields produced per cubic meter of water used, thereby minimizing environmental contamination.

Beschreibung: At the request of the French Ministry for Ecological and Inclusive Transition (MTES) and the French Biodiversity Agency (AFB), INRAE carried out a study focusing on the creation of a national asset knowledge base for drinking water networks, operating at Water Agency (WA) scale. Our study involved the creation of a number of statistical models. These models combine data relating to network characteristics (gathered from a sample of utilities) with geographical and demographical data collected from all municipalities in France. The SISPEA database, along with geographical information system (GIS) data from a sample covering around half of the total French drinking water network, were used to configure multilinear pipe models by diameter, installation period and type of material. On the basis of these models, the total length of drinking water pipes in mainland France was estimated to be 875,000 km. Networks are quite young (60% of the total length was laid after 1970), small diameter pipes are the majority (70% of the pipes have a diameter less than or equal to 100 mm) and the materials used are linked on geographic areas (pipes are mainly made of PVC in the west of France while cast iron pipes predominate in the other regions).

Beschreibung: Palm oil mill effluent (POME) is a hazardous wastewater which contains high organic constituents and salt concentrations. The ultrafiltration (UF) process is a promising treatment design used for secondary treatment such as POME. However, membrane fouling is the major problem which limits the performance of the UF. This paper describes a detailed investigation of polyvinylidiene fluoride (PVDF) membrane for the treatment of POME. The fouling behavior was analyzed by water flux, fouling mechanism, scanning electron microscopy (SEM), particle size distribution (PSD) and Energy Dispersive X-ray (EDX). It was found that a significant reduction in the permeate flux was caused by the build up of a fouling layer. Study on the fouling mechanism shows that cake filtration dominated the fouling activities on the membrane surface, compared to standard blocking, intermediate blocking, and complete blocking. This result is supported by membrane autopsy through SEM, PSD and EDX.

Beschreibung: Estimating stream flow has a substantial financial influence, because this can be of assistance in water resources management and provides safety from scarcity of water and conceivable flood destruction. Four common statistical methods, namely, Normal, Gumbel max, Log-Pearson III (LP III), and Gen. extreme value method are employed for 10, 20, 30, 35, 40, 50, 60, 70, 75, 100, 150 years to forecast stream flow. Monthly flow data from four stations on Mahanadi River, in Eastern Central India, namely, Rampur, Sundargarh, Jondhra, and Basantpur, are used in the study. Results show that Gumbel max gives better flow discharge value than the Normal, LP III, and Gen. extreme value methods for all four gauge stations. Estimated flood values for Rampur, Sundargarh, Jondhra, and Basantpur stations are 372.361 m3/sec, 530.415 m3/sec, 2,133.888 m3/sec, and 3,836.22 m3/sec, respectively, considering Gumbel max. Goodness-of-fit tests for four statistical distribution techniques applied in the present study are also evaluated using Kolmogorov–Smirov, Anderson–Darling, Chi-squared tests at critical value 0.05 for the four proposed gauge stations. Goodness-of-fit test results show that Gen. extreme value gives best results at Rampur, Sundergarh, and Jondhra gauge stations followed by LP III, whereas LP III is the best fit for Basantpur, followed by Gen. extreme value.

Beschreibung: In this work, δMnO2 was anchored into graphene nanosheets via a mediated simple and eco-friendly approach to be used as a potential low-cost cathodic catalyst in microbial desalination cells (MDC). MnO2/G based MDC revealed a faster start-up and stable performance during the operation compared with the catalyst-free control MDC. The average chemical oxygen demand (COD) removal efficiencies were 85.11 ± 5.13 and 86.20 ± 4.85% and average columbic efficiencies throughout the operation cycles were 1.52 ± 0.32% and 0.70 ± 0.35% for MnO2/G based reactor and control reactor, respectively. The average desalination efficiencies were 15.67 ± 3.32 and 13.21 ± 2.61% for MnO2/G based reactor and control reactor, respectively. The superior catalytic performance of MnO2/G based cathode improved current generation which is the key desalination stimulus. MnO2/G based reactor revealed a lower internal resistance of 430 Ω compared with 485 Ω for the catalyst-free control reactor and, similarly, the maximum power densities were found to be 12.5 and 6.5 mW/m2, respectively. MnO2/G catalyst offered an improved MDC performance, however, still with uncompetitive performance in comparison with platinum group metals catalysts.

Beschreibung: The American Water Works Association (AWWA) has developed and disseminated advanced methods and performance indicators for assessing and reducing water losses in North America, based in large part on the methods and indicators developed by the International Water Association (IWA). However, many utilities and regulators still use the old, inaccurate, %NRW indicator. A robust, quantitative assessment of the technical rigor of water loss indicators was needed but could not be found in the literature. So, an innovative approach was developed, using Frontier Analysis which provided such a score of ‘technical rigor’. This paper presents this method, applied to three datasets from North America, assessing 15 candidate indicators for total water losses, apparent losses and real losses. The results provide quantitative ‘scores’ of the technical rigor of the candidate indicators. Indicators with relatively high scores align with indicators used in the IWA best practices. Other indicators, such as the %NRW indicator, were found to have low technical rigor. The conclusion of the paper summarizes the rigorous indicators, and suggests areas for further application of this method, and for further research.

Beschreibung: Flood inundation simulation models are widely used for simulating severe events of flood, generating hazard maps, risk assessment, and to identify flood vulnerable locations. It is important to assess the degree of accuracy of flood model results as these results may be one of the triggering parameters considered in developing flood hazard maps, flood mitigation policies, and land using planning where multi-criteria analysis is approached. In the present study, an algorithm is developed in order to know the performance of flood models by validating it with flood footprints extracted from synthetic aperture radar (SAR) images using multi-segmentation and Otsu's thresholding technique. Evaluation of the performance of the model is based on two best fit criteria called F1 and F2. For this, HEC-RAS model is used for simulating the severe event of flood witnessed in Mahanadi River in Odisha stretching between Tikarpara and Mundali during September 2008.Three simulations were made by considering three different Manning's roughness for river and floodplain. The model gives appreciable results and best fit F1 = 0.85 and F2 = 0.74 was found for Manning's roughness 0.020.

Beschreibung: NO3-N and dye colors discharged from textile wastewater pose environmental problems in Thailand. This study aimed to observe the nitrogen removal rate (NRR) with and without RB-5 color contamination via hydrogenotrophic denitrification (HD) processing, which uses H2 gas as electron donor to reduce NO3-N and NO2-N; comparing with bioreactors treatment to evaluate systems that can simultaneously remove NO3-N and dye color. Five reactors under different operation and gas supply conditions were set-up under HRT of 24 h, including an aerobic reactor using air, two anaerobic reactors using argon and H2, and a combined process using intermittent air/argon and air/H2. NRR without dye varied between 45 and 90% for H2 and air/H2 by HD processing, while it was completely removed when adding color. H2 and air/H2 reactors experienced partial decolorization of approximately 20–30%, whereas the other three reactors remained unchanged. Effluent of NO3-N were close to wastewater standards, but the color was still easy to detect, which indicated that the treatment time needs to be sufficient. In conclusion, HD and intermittent air/H2 processing can completely remove NO3-N and NO2-N when contaminated with RB-5 color. Furthermore, RB-5 did not affect the NRR, whereas some particles of dye color can also reduce in these processes.

Beschreibung: During the last three decades, the water resources engineering field has received a tremendous increase in the development and use of meta-heuristic algorithms like evolutionary algorithms (EA) and swarm intelligence (SI) algorithms for solving various kinds of optimization problems. The efficient design and operation of water resource systems is a challenging task and requires solutions through optimization. Further, real-life water resource management problems may involve several complexities like nonconvex, nonlinear and discontinuous functions, discrete variables, a large number of equality and inequality constraints, and often associated with multi-modal solutions. The objective function is not known analytically, and the conventional methods may face difficulties in finding optimal solutions. The issues lead to the development of various types of heuristic and meta-heuristic algorithms, which proved to be flexible and potential tools for solving several complex water resources problems. This paper provides a review of state-of-the-art methods and their use in planning and management of hydrological and water resources systems. It includes a brief overview of EAs (genetic algorithms, differential evolution, evolutionary strategies, etc.) and SI algorithms (particle swarm optimization, ant colony optimization, etc.), and applications in the areas of water distribution networks, water supply, and wastewater systems, reservoir operation and irrigation systems, watershed management, parameter estimation of hydrological models, urban drainage and sewer networks, and groundwater systems monitoring network design and groundwater remediation. This paper also provides insights, challenges, and need for algorithmic improvements and opportunities for future applications in the water resources field, in the face of rising problem complexities and uncertainties.

Beschreibung: Between 2015 and 2018, the Western Cape region of South Africa experienced three consecutive years of below average rainfall. The local authority of Cape Town imposed water restrictions to avert ‘Day Zero’, an event that was expected to occur if the storage capacity of the main dams supplying the city fell to below 13.5%. This study analyses how different residential areas in Cape Town responded to water restrictions and tariffs that were imposed from January 2016 to October 2018 during the midst of the water crisis. It further explores the potential implications for tariff adjustments that were designed to sustain water conservation measures beyond the drought, while also being sensitive to the ability of poorer households to access sufficient water at an appropriate per capita cost. Different socio-economic groups displayed a different response to the restrictions. A delay or lag-time was observed in lower-income suburbs during the initial phases of water restrictions, while middle- and higher-income suburbs responded immediately. Once the water crisis eased by mid-2018 and restrictions were reduced, more affluent suburbs began relaxing their water conservation efforts. Nevertheless, lower-, middle-, and higher-income suburbs significantly reduced their water demand by 32, 59, and 58%, respectively, over the study period. It can therefore be concluded that water restrictions and accompanying tariffs altered water use of all users regardless of socio-economic status.

Beschreibung: Recently, physically-based hydrological models have been gaining much popularity in various activities of water resources planning and management, such as assessment of basin water availability, floods, droughts, and reservoir operation. Every hydrological model contains some parameters that must be tuned to the catchment being studied to obtain reliable estimates from the model. This study evaluated the performance of different evolutionary algorithms, namely genetic algorithm (GA), shuffled complex evolution (SCE), differential evolution (DE), and self-adaptive differential evolution (SaDE) algorithm for the parameter calibration of a computationally intensive distributed hydrological model, variable infiltration capacity (VIC) model. The methodology applied and tested for a case study of the upper Tungabhadra River basin in India, and the performance of the algorithms is evaluated in terms of reliability, variability, efficacy measures in a limited number of function evaluations, their ability for achieving global convergence, and also by their capability to produce a skillful simulation of streamflows. The results of the study indicated that SaDE facilitates an effective calibration of the VIC model with higher reliability and faster convergence to optimal solutions as compared to the other methods. Moreover, due to the simplicity of the SaDE, it provides easy implementation and flexibility for the automatic calibration of complex hydrological models.

Beschreibung: Decision trees are ideally suited for handling huge datasets and modelling non-linear relationships between different variables. Given the relationship between precipitation and bias may be very complex and non-linear, bias-correction of satellite precipitation is a challenge. We examine the applicability of Classification and Regression tree (CART) for bias-correction of the Integrated Multi-satellite Retrievals for Global Precipitation Mission (IMERG) precipitation dataset over India. The gauge-based 0.25° gridded precipitation dataset from India Meteorological Department is considered as the reference. The CART model is trained (2001–2011) and tested (2012–2016) over each 0.25° grids. The training dataset is subjected to 10-fold cross-validation and optimization of the minimum size of leaf node (one of the hyper-parameter). Efficiency of the CART model is evaluated using performance metrics like R2, RMSE and MAB over the whole of India and different climate and elevation zones in India. CART model is observed to be highly effective in capturing the bias during the training (average R2= 0.77) and testing (average R2 = 0.66) period. Significant improvement in average monthly MAB (−6.3 to 29.2%) and RMSE (8.7–37.3%) was obtained post bias-correction by CART. Better performance of CART model was observed when compared to two widely adopted bias-correction techniques.

Beschreibung: Urban communities in developing countries are one of the most vulnerable areas to extreme rainfall events. The availability of local information on extreme rainfall is therefore critical for proper planning and management of urban flooding impacts. This study examined the past and future characteristics of extreme rainfall in the urban catchments of Dar es Salaam, Tanzania. Investigation of trends and frequency of annual, seasonal and extreme rainfall was conducted, with the period 1967–2017 taken as the past scenario and 2018–2050 as the future scenario; using data from four key ground-based weather stations and RCM data respectively. Mann–Kendall trend analysis and Sen's slope estimator were used in studying changes in rainfall variability. Frequencies of extreme rainfall events were modeled using the Generalized Pareto model. Overall, the results of trend analysis provided evidence of a significant increase in annual and seasonal maximum rainfall and intensification of extreme rainfall in the future under the RCP4.5 CO2 concentration scenario. It was determined that extreme rainfall will become more frequent in the future, and their intensities were observed to increase approximately between 20 and 25% relative to the past. The findings of this study may help to develop adaptation strategies for urban flood control in Dar es Salaam.

Beschreibung: Effective quantitative and qualitative management of water for irrigation is crucial in many regions and the use of reclaimed water is a possible solution. Quantifying the impact of the use of such water is thus important. Using life cycle assessment methodology, this study analyzes the impact of water reuse irrigation and farmers’ practices in greenhouse cucumber production. Three scenarios concerned sources of water for irrigation and agricultural practices: the first scenario used surface water including reclaimed water, the second used groundwater. The third scenario resembled the first but also accounted for fertilizer application based on theoretical cucumber requirements. The third scenario showed 35% less fertilizer is required than the quantities farmers actually use. Our results show that the higher environmental impact of irrigation using reclaimed water than using groundwater is mainly due to over-fertilization. Comparison of the first and third scenarios also showed that the reduction in the environmental impact under the third scenario was significant. We conclude that LCA is a useful tool to compare the impacts of different water sources and farmers’ irrigation/fertilization management practices, and in particular, that the quantity of nutrients in reclaimed water should be deducted from the actual amount applied by the farmers.

Beschreibung: Modelling of runoff is a significant practice in water resources engineering. Therefore, discovering consistent and advanced methods for prediction of runoff is crucial for hydrologic processes. Here, a narrative integrated intelligence model attached with PSR (phase space reconstruction) is anticipated to estimate runoff for five watersheds of Balangir, Odisha, India. Monthly monsoon precipitation, temperature, humidity data of five watersheds over 28 years (1990–2017) are employed and validated. Here, the proposed model is an integration of support vector machine (SVM) with firefly algorithm (FFA) and PSR. Various indices like NSE (Nash–Sutcliffe), RMSE (root mean square error) and WI (Willmott's index) are used to find the performance of the model. The developed PSR-SVM-FFA model demonstrates pre-eminent WI value ranging from 0.97 to 0.98 while the SVM and SVM-FFA models encompass 0.92 to 0.93 and 0.94 to 0.95, respectively. Also an assessment of data from the suggested model is schemed and validated. The proposed PSR-SVM-FFA model gives better accuracy results and error limiting up to 2–3%.

Beschreibung: Optimizing the efficiency of urban water systems is a growing concern for water utilities worldwide. Wastewater treatment plants (WWTP) are crucial in maintaining water quality and resource recovery in a world facing growing challenges such as climate change, water-energy-food nexus and the increase of legal requirements and users' expectations. Thus, adopting a performance assessment system (PAS) is of the utmost importance to assess operating conditions and to identify critical aspects of the WWTP which can negatively affect its effectiveness, efficiency and reliability. This paper presents the global and operational performance assessment of an urban WWTP and identifies improvement measures. The WWTP presented a good performance in terms of effectiveness and reliability. Nevertheless, in terms of efficiency, relevant improvement opportunities were identified, specifically in the sludge treatment phase and in terms of energy management. PAS was proven to be successful in the identification and prioritization of rehabilitation needs in a systematic way which will continuously improve the efficiency and effectiveness of the WWTP as well as to support asset management decisions regarding their upgrade and retrofit.

Beschreibung: This paper presents the results of electrochemical oxidation of dye-containing wastewater over a BDD anode. Batch experiments were conducted at a fixed current density of 2.8 mA/cm2 to analyze the performance of the electrochemical process for the treatment of textile and paint wastewater utilizing different supporting electrolytes (Na2SO4 and NaCl). During electrolysis, emphasis was put on measuring different parameters such as COD, turbidity, conductivity, and color removal. The results revealed that BDD cell exhibited higher COD removal efficiency for textile wastewater than for paint wastewater. Adding supporting electrolytes had a positive effect on COD, turbidity, and color removal efficiencies for both textile and paint industry effluents. For textile wastewater, Na2SO4 and NaCl yielded a reduction in COD of 94% in 6 hours compared to 84% with no electrolyte added. The presence of Na2SO4 and NaCl in paint wastewater resulted in different COD removal percentages of 71 and 85% respectively with 21% in raw sample after 4 hours of treatment. The discoloration reached a percentage higher than 96% for both effluents and for both electrolytes. Under the same experimental conditions, all cases showed turbidity removal higher than 97%. The kinetic study showed that the reaction rate followed pseudo-first-order kinetics.

Beschreibung: Urban water supply, wastewater and storm water services (globally, water services) are essential to society. The lack of permanent, safe, and respondent services has inevitable consequences on public health and the well-being of communities, on the economy, and on the environment. Goal 6 of the Sustainable Development Goals (SDGs) recognizes this; failing to meet it necessarily affects the accomplishment of many of the other SDGs. Water services’ provision depends on expensive and long-lasting physical assets. Managing them strategically (e.g., according to the international standards on asset management, series ISO 55x and to the IWA recommendations on infrastructure asset management) is, therefore, fundamental for sustainable societies. Countries need to have sound public policies that enable asset management of water infrastructures. Portugal is a paradigmatic case. This paper elaborates on key government goals, on why asset management is important to meet them, and on key building blocks that a coherent public policy should consider in order to enable asset management of water infrastructures. It also presents how Portugal has been implementing this process, addressing the challenges to overcome.

Beschreibung: Treated wastewater is expected to constitute an essential part of the urban water cycle as an additional water resource in water-scarce or densely populated regions in the future. As decisions on the implementation of water recycling measures should always consider local conditions, the project ‘MULTI-ReUse: Modular treatment and monitoring for wastewater reuse’ has developed a comprehensive sustainability assessment tool, designed to support decision-makers in examining the technical feasibility, economic viability, ecological compatibility and social acceptance of alternative service water supply solutions at local level. This article describes the structure of this sustainability assessment tool and its underlying multi-criteria assessment approach based on 23 evaluation criteria. Already in the development phase, the tool was tested in a German and a Namibian case study. Both case studies are presented with a special focus on the technologies used and the results of the analysis with the sustainability assessment tool. Case study testing proved that the tool is applicable in various environmental and societal settings with widely differing climatic conditions, limited resource availability, for varying feed water qualities and water quality requirements. The comprehensive, straightforward assessment approach enabled the local users to identify the most sustainable supply system or strategy for their decision case.

Beschreibung: Industrial wastewater reuse is a major measure to mitigate the depletion of available freshwater resources in the catchments around industrial areas and to prevent possible future water shortages and the resulting problems for industry, economy and society. Combining a set of environmental aspects and economic aspects of different wastewater treatment technologies, the authors develop a model-based approach for planning and evaluating water reuse concepts in industrial parks. This paper is based on an exemplary Model Industrial Park. The results based on data primarily calculated for Germany show that, for the majority of the indicators, the installation of the Water Reuse Plant seems to be beneficial for all examined reuse options. Considering the economic dimension, due to economies of scale, reuse options with larger volumes of treated water are preferable since the costs per m3 of reuse water are reduced up to 33%. On the other hand, the environmentally preferable option depends on the respective indicator, e.g. for freshwater eutrophication, the higher the reuse factor, the lower the impact, leading to reductions between 8 and 12%. For climate change, the best option is dependent on the reuse purpose leading to reductions between 8 and 52%.

Beschreibung: Due to water scarcity and water pollution, the importance of water reuse is increasing more and more. As part of a German research programme on water reuse, the effluent of a wastewater treatment plant in the coastal region of northern Germany was used to investigate the direct treatment of tertiary effluent within the project MULTI-ReUse. A modular constructed pilot system has been operated to optimize different treatment chains producing different water qualities simultaneously. The technological focus was put on membrane technologies, namely ultrafiltration (UF) and reverse osmosis (RO), and also biofiltration, adsorption and disinfection were part of the piloting. Beside the development of monitoring strategies for ensuring biological and chemical safe water qualities, the operational stability and the safe transport of water to the consumers were examined. The direct treatment of wastewater is a demanding task due to the lack of dilution and hydraulic retention time in the receiving water (environmental buffer). However, the multiple barrier approach guaranteed constant secure water. Fine adjustments of individual processes were particularly important. A stable operation of the UF could be realized in particular by using more or less intermitting inline coagulation as coating. The RO performance could be improved significantly by using monochloramine as disinfectant to minimize biofouling.

Beschreibung: The present understanding of how changes in climate conditions will impact the flux of natural organic matter (NOM) from the terrestrial to aquatic environments and thus aquatic dissolved organic carbon (DOC) concentrations is limited. In this study, three machine learning algorithms were used to predict variations in DOC concentrations in an Australian drinking water catchment as a function of climate, catchment and physical water quality data. Four independent variables including precipitation, temperature, leaf area index and turbidity (n = 5,540) were selected from a large dataset to develop and train each machine learning model. The accuracy of the multivariable linear regression, support vector regression (SVR) and Gaussian process regression algorithms with different kernel functions was determined using adjusted R-squared (adj. R2), root-mean-squared error (RMSE) and mean absolute error (MAE). Model accuracy was very sensitive to the time interval used to average climate observations prior to pairing with DOC observations. The SVR model with a quadratic kernel function and a 12-day time interval between climate and water quality observations outperformed the other machine learning algorithms (adj. R2 = 0.71, RMSE = 1.9, MAE = 1.35). The area under the receiver operating characteristic curve method (AUC) confirmed that the SVR model could predict 92% of the elevated DOC observations; however, it was not possible to estimate DOC values at specific sampling sites in the catchment, probably due to the complex local geological and hydrological changes in the sites that directly surround and feed each sampling point. Further research is required to establish potential relationships between climatological data and NOM concentration in other water catchments – especially in the face of a changing climate.

Beschreibung: Stricter environmental regulation policies and freshwater as an increasingly valuable resource are leading to global growth of zero liquid discharge (ZLD) processes in recent years. During this development, in addition to water, the recovery of recyclable materials, e.g. salts, from industrial wastewater and brines is considered more frequently. Within the framework of the HighCon research project, the subject of this study, a new ZLD process with the goal of pure single-salt recovery from industrial wastewater has been developed and investigated in a demonstrational setup at an industrial site. With regard to pure salts recovery, separating organic components is of great importance during the treatment of the concentrate arising from used water recycling. The removal of COD and of ions responsible for scaling worked very well using nanofiltration. The nanofiltration permeate containing the monovalent ions was pre-concentrated using electrodialysis and membrane distillation before selective crystallization for single-salt recovery was performed. An example economic case study for the newly developed ZLD process – based on demonstration results and considering optimization measures for a full-scale design – indicates that the costs are equal to those of a conventional ZLD process, which, however, does not provide inter alia the aforementioned benefit of single-salt recovery.

Beschreibung: The adsorption of Congo red onto titanium dioxide (TiO2) material has been investigated at batch conditions. The effects of contact time (0–60 min), initial pH (3–11), agitation speed (100–500 rpm), temperature (298–343 K), adsorbent dosage (0.5–2 g/L), and Congo red concentration (5–15 mg/L) on the Congo red adsorption by TiO2 have been studied. The kinetic parameters, rate constants, and equilibrium adsorption capacities were calculated and discussed for each kinetic model. The adsorption of Congo red onto TiO2 is well described by the pseudo-second order equation. The adsorption isotherm follows the Langmuir model, providing a better fit of the equilibrium data. The batch adsorption experiments were carried out to optimize the physical parameters on the Congo red removal efficiency. It has been found that 152 mg/g at 25 °C is removed. The thermodynamic parameters indicate the spontaneous and endothermic nature of the adsorption process with activation energy (Ea) of −64.193 kJ/mol. The positive value of the entropy (ΔS°) clearly shows that the randomness is decreased at the solid–solution interface during the Congo red adsorption onto TiO2, indicating that some structural exchange may occur among the active sites of the adsorbent and the ions.

Beschreibung: Water reuse is becoming an increasing necessity due to depleted water resources or increased water demand. A treatment process on a pilot scale was designed to produce different water qualities for different applications in industry or agriculture. We report here microbiological changes along the modular process using treated municipal wastewater effluent as raw water. Treatment technologies included coagulation, ultrafiltration (UF), reverse osmosis (RO), quartz sand and activated granular activated carbon (GAC) filtration and disinfection. Elimination of traditional hygiene indicator bacteria was already achieved by ultrafiltration as the first barrier. Profound changes by each treatment step also applied to the microbiome. Total and intact cells concentrations as quantified by flow cytometry underwent a strong decline after UF and RO, whereas biological stabilization was achieved through quartz sand filtration and GAC passage. Interestingly assimilable organic carbon (AOC) was still present at levels that allowed substantial regrowth of bacteria. Overall, UF and RO led only to a 0.43 and 0.78 log decrease in intact cells concentrations in stagnated water after regrowth compared with 6.5 log intact cells/ml in the stagnated raw water. Temperature was shown to be an important parameter determining the microbiome of the regrown population. Regrowth could, however, be efficiently suppressed by monochloramine.

Beschreibung: Within the research project HypoWave, a hydroponic system for plant production was investigated. The hydroponic system was fed with wastewater that had undergone specially adapted treatment. The principal aim was to develop a combined system for water treatment and hydroponic plant production, where water and nutrients were reused efficiently to produce marketable food products. Another goal was to find out whether the reuse of pre-treated wastewater for plant growth in a hydroponic system could also present an additional alternative wastewater treatment step for enhanced nutrient removal. A pilot plant, consisting of various treatment steps such as activated sludge process, ozonation and biological activated carbon filtration, was used to produce lettuce with irrigation water of different qualities. The hydroponic pilot plant was operated in two different modes – flow-through and feed & deplete. This paper focuses on the influence of the various modes of operation and accordingly varying nutrient concentrations (N, P, K) on plant growth. Furthermore, heavy metal content in the various types of treated wastewater and in the produced plants was investigated. In addition, the results of the different modes of operation were verified by mass balances for N, P and K.

Beschreibung: Against the background of drastically rising global water demand and increasing pollution and overexploitation of regional water resources, the demand-driven water supply of households and industry is of central importance. Water reuse and desalination are seen as key technologies to overcome potential regional and local water shortage. In the joint projects funded by the German Federal Ministry of Education and Research (BMBF) ‘Future-oriented Technologies and Concepts to Increase Water Availability by Water Reuse and Desalination (WavE)’, evaluation approaches for analysing innovative technologies and concepts are being developed and assessed. All evaluation methods and criteria used were selected based on the decision situation at hand and the decision-makeŕs preferences. Based on the analysis of six multi-criteria evaluation concepts used in selected WavE projects, this paper presents a general approach for comparative multi-criteria evaluation of water reuse systems consisting of prerequisites, minimum requirements, evaluation criteria (qualitative, semi-quantitative or quantitative) and a final aggregation of results. Exemplary sets of criteria for the application in a more industrial, municipal and/or international context are presented as an aid for the application of holistic evaluation approaches for (process) concept and technology selection in the context of water reuse and desalination.

Beschreibung: The impact of climate change upon the hydrological regimes of streams has become an issue of major concern that requires adapted tools to detect and follow the scale of possible changes. In this study, we use a geochemical approach that exclusively relies on measurements of chemical concentrations in order to investigate the effect of climate change on the hydrological regime of the River Arve, a Franco-Swiss river running from the Alps to the River Rhône. Our method relies on the use of a dimensionless parameter, the ratio of uranium and barium concentrations in river waters. This marker has the advantage of not needing the measurement of river discharges. Its application to 25 years of data collected in the River Arve by Canton Geneva, Switzerland, leads to the conclusion that the glacio-nival signature is appearing earlier in the year and lasts for longer periods.

Beschreibung: Industrial parks (IPs) play a significant role in the context of economic growth as well as urban and regional development strategies. They rely on the availability of factors of production and an enabling environment, which also includes the legal framework and economic conditions. The availability of water is essential for the operation and expansion of IPs. Sustainable, efficient and reliable water supply is crucial for IPs and the companies located in the IPs. Reusing wastewater to reduce the amount of drinking or process water necessary for production requires economically viable treatment processes. From an economic point of view, it is important to compare the costs of different treatment trains and to ensure that technical solutions generate an economic benefit for the operators of the IPs. Based on data from municipal wastewater treatment, the authors derive cost functions for individual treatment processes and develop tools for a modular economic assessment of water reuse in IPs.

Beschreibung: Water-saving agricultural practices can reduce negative environmental impacts in water-scarce regions all over the world. This study deals with an innovation that combines hydroponic crop production and municipal wastewater reuse for irrigation purposes. The research question was what impacts such hydroponic water reuse systems have on product confidence, economic viability, groundwater recharge, biodiversity and landscape quality. It should also be clarified under which conditions and with which measures these systems can be sustainable. To answer these questions, a number of generic hydroponic water reuse systems were modeled and assessed using a Bayesian Belief Network that included both numerical values and expert knowledge. The hydroponic water reuse systems with the most positive overall impacts are small-scale food production systems (tomatoes) equipped with lighting and heating whose products are marked with a quality label or with a label for regional products. The systems are located in a former industrial area. In addition, a wetland system and landscape integration are implemented as landscaping measures. Hydroponic systems can be operated economically viable, their products have a high level of product confidence and their ecological impacts can be positive. No tradeoffs have to be accepted between economic, social and ecological goals.

Beschreibung: The HypoWave transdisciplinary research project investigated the innovation of water reuse in a hydroponic system, focusing on its applicability in Germany. The methods applied were the operation of a pilot plant for the appropriate treatment and subsequent reuse of water in a hydroponic system, expert interviews, feasibility studies, an impact assessment and a stakeholder dialogue. To identify the concept's advantages and disadvantages, publications specialising in the various disciplines involved and meeting protocols were analysed and the results grouped together in a SWOT (strengths, weaknesses, opportunities and threats) analysis. This revealed that the system has potential for application in Germany subject to certain requirements being met, such as suitable local wastewater treatment conditions and actors looking for new business opportunities within agricultural production. This system is not recommended for the country as a whole, but it does offer an interesting alternative for locations that meet the appropriate conditions. Nevertheless, additional efforts and knowledge are required to promote and operate a new system of this kind. These include the reliable supply of irrigation water with guaranteed plant nutrition, comprehensive quality management to manage potential risks, a good understanding of the cooperation arrangements required and a more detailed examination of energy aspects.

Beschreibung: The objective of the present work is to determine an optimal cropping pattern under uncertainty, which maximizes four objectives simultaneously, including net benefits (NBF), crop production (CPD), employment generation (EGN) and manure utilization (MUT). Except the objective of maximizing the NBF, the other objectives are related to sustainability. To deal with uncertainty, a multi-objective fuzzy linear programming (MOFLP) model has developed along with fuzziness in decision parameters (objective function coefficient, cost coefficients, technological coefficients and resources) and decision variables (area to be irrigated under each crop in each season) and applied the same to Jayakwadi Project Stage-I, Maharashtra, India. The present study is in the form of a successful attempt to deal with irrigation planning associated with sustainability and uncertainty.

Beschreibung: Water and wastewater tariffs constitute a primary avenue for utilities to generate revenue towards covering the costs associated with water and wastewater service provisions. In the pursuit of achieving global access to safe and affordable water and sanitation, utilities and governments play an important role in regulating and setting combined tariffs, so that they are able to fund the necessary infrastructure while at the same time ensuring that tariffs do not impede on the ability of consumers to access these services. From a survey of 568 cities across 192 countries, this paper examines the main economic and financial drivers of change to regional urban water and wastewater tariffs from 2018 to 2019. Historically, the average global price for water and wastewater services increased from US$ 1.70/m3 in 2011 to US$ 2.16/m3 in 2019, equating to an annual rise in the mean global combined water tariff of ∼3.4%. The analysis indicates that for the studied regions, the financial and economic costs associated with recurring droughts, old infrastructure, subsidy cuts, increasing energy costs and a shift to alternative water resources such as desalination all contribute to changes in tariffs. Further research on the social and political drivers of change in tariffs is needed, in order to provide a holistic understanding of the balance required to be struck between the objectives of affordability and cost-recovery for achieving global access to water and sanitation.

Beschreibung: The internet of things (IoT), an emerging technological marvel, consists of a group of physical objects such as vehicles, machines and sensors to monitor and transfer data over the internet with much less human to machine interaction. It relies on a host of technologies like application programming interfaces (API), which in turn, help the devices to get connected with the internet. Efficient irrigation tank management requires a strong database on continuous water level dynamics for irrigation decision-making. Real-time tank water level monitoring is possible through an IoT device by integrating sensors and microcontroller that can send the water level data to the cloud. Google sheet is used to store the water level data that can be viewed using web application as well as mobile application. The contour map of the study tank is used to develop the stage (water level) vs volume curve. The volume of water present in the tank at any time can be arrived at for any tank water level using the above curve. The developed device can provide real-time continuous water level data with low cost and simple infrastructure, thus aiding tank water management.

Beschreibung: Hydrodynamic models for morphodynamic studies in estuaries require continuous tidal water level data as boundary conditions. However, for the Hooghly estuary in India, measurement of continuous tidal water elevation data at the most downstream point is a very difficult task because of the remote location and the confluence with the deep sea. The tidal water level data at this station are measured for a half tidal cycle which is not useful for hydrodynamic modeling. However, at other upstream stations, tide water level data are measured continuously. Accordingly, in this study, an attempt is made to generate continuous tidal water level data at the remote station, using the data of the neighboring stations as input to an artificial neural network (ANN) model. A three-layered feed-forward backpropagation (FFBP) network with two hidden layers is selected and five different combinations of input vectors are used. Simulated water level data obtained from each model are compared with the observed data graphically as well as by estimating the standard error parameters. The best model suitable for prediction of continuous tidal elevation during any time of the tidal cycle and applicable throughout the year is then identified. It is found that tidal data from the nearest neighboring station is more suitable for training.

Beschreibung: An ever-increasing volume of saline effluents from industries, oil–gas fields, and desalination plants has resulted in an enormous amount of pollutants with undesirable effects on the environment and human health. Adequate disposal and treatment of these effluents remains a persistent problem and poses significant technical as well as economic challenges. Saline effluents can have considerable environmental impacts, depending upon the sensitivity of the surrounding ecosystems. Conventional disposal techniques mostly suffer from direct or indirect contamination of water/soil and are no longer preferred. As a result, several advanced treatment methods are being considered for sustainable saline effluent management in recent times. In this context, a comprehensive and updated review of conventional methods, along with emerging technologies for disposal and treatment of saline effluent, is presented. Existing treatment approaches, including membrane operation, thermal processes, chemical techniques, and biological methods, are discussed. The application of innovative hybrid processes (combining two or more treatment methods) aiming at lower energy demand and higher treatment efficiency has also been evaluated. Subsequently, emerging sustainable strategies like waste minimization & water recovery, zero liquid discharge, and resource recovery for saline effluents have been examined. The prospect of integrating the renewable energy sources with energy-intensive saline treatment methods towards energy–water–environment nexus is also explored.

Beschreibung: To evaluate energy efficient concepts for the modular treatment of brackish water, pilot trials for groundwater desalination and arsenic (As) removal were carried out in the Mekong Delta, Vietnam. Groundwater here is affected by naturally occurring high iron (Fe2+) and As concentrations, while, in coastal regions, groundwater is additionally contaminated by high salinity mostly due to seawater intrusion. Desalination was conducted by membrane capacitive deionization (MCDI), which shows low specific energy consumption (SEC). Anoxic groundwater with As(III) and Fe2+ was treated using a pre-oxidation step called subsurface arsenic removal (SAR) with the main advantage that no As-laden waste is produced. The pilot plant was operated using a photovoltaic system (3 kWp) and a small wind turbine (2 kWp). The SEC of drinking water produced was 3.97 kWh/m3. Total dissolved solids (TDS) of 1,560 mg/L were lowered to 188 mg/L, while Fe2+ was reduced from 1.8 mg/L to the below detection limit and As from 2.3 to 0.18 μg/L. The results show that SAR is a feasible remediation technique for Fe2+ and As removal in remote areas, and demonstrate the potential of MCDI for brackish water desalination coupled with renewable energies. However, improvements in energy demand of the MCDI module can still be achieved.

Beschreibung: This study focuses on the removal of three model compounds, classified as emerging persistent organic pollutants (Em-POPs), from water using a modified version of natural Australian zeolite. Following a series of subsequent treatments and vacuum deposition of graphene oxide (GO), both chemical and physical properties of the adsorbent were characterized. The GO-coated zeolite was tested for the removal of methylene blue (MB), disperse blue 26 (DB26), and sodium fluorescein (NaFn). Results show excellent removal capability for MB and DB26 dyes and decent removal for NaFn when compared to commercially available products such as granular activated carbon. Regeneration of the adsorbent showed virtually no loss in adsorptive performance after two cycles, with MB and DB26.

Beschreibung: The removal of brilliant green dye (BGD) from aqueous solution by using Salix alba leaves (SAL) was carried out via batch studies. The maximum removal efficiency was found to be 95.2% with initial dye concentration 50 mg/L at 0.15 g adsorbent dosage, pH = 6, and 298 K temperature, and the equilibrium was observed within 3½ hours. The adsorption capacity increased (2.21–15.89 mg/g) from 10 to 50 mg/L of dye concentration. Kinetic and isotherm studies were also carried out. The results showed that pseudo-second order model better describes the adsorption mechanism. The isotherm equilibrium data analysis was carried out by using Freundlich and Langmuir models and the sorption process was observed to conform with the Langmuir isotherm with linear correlation coefficient (R2 = 0.99). The thermodynamic properties ΔG°, ΔH°, and ΔS° delineated that BGD adsorption over SAL was feasible, spontaneous, and endothermic between 303 and 323 K temperature.

Beschreibung: The modified topographic index () based on digital elevation models (DEMs) was employed to delineate flood-prone areas in Mahanadi basin, India. and flood inundation maps were compared to obtain the threshold () beyond which the area is assumed to be inundated by flood and the exponent of the . Scale dependence was also investigated to evaluate the sensitiveness of spatial resolution of the DEMs. DEMs of five resolutions, namely, ASTER global, SRTM, GMTED2010 (30 arc-seconds), GMTED 2010 (15 arc-seconds), and GMTED 2010 (7.5 arc-seconds), were used and ASTER global was preferred due to its low error compared to the remainder. Flood frequency analysis was conducted to obtain the relationship between flood-prone areas and flood magnitude. It was observed that (i) the exponent in the showed little variation, (ii) is reduced with reducing spatial resolution of the DEM, and (iii) error is also reduced as the DEMs' resolution is reduced.

Beschreibung: Chemical cleaning with hypochlorite is routinely used in membrane-based processes. However, a high-transient cleaning efficiency does not guarantee a low biofouling rate when filtration is restarted, with the physiological mechanisms largely remaining unknown. Herein, we investigated the microbial regrowth and surface colonization on membrane surfaces after NaOCl cleaning had been completed. Results of this study showed that the regrowth of model bacteria, Pseudomonas aeruginosa, was initially subject to inhibition due to the damage of key enzymes' activity and the accumulation of intracellular reactive oxygen species although the oxidative stress induced by NaOCl had been removed. However, with the resuscitation ongoing, the stimulatory effects became obvious, which was associated with the enhanced production of N-acyl homoserine lactones and the secretion of eDNA that ultimately led to more severe biofouling on the membrane surface. This study elucidates the inhibition–stimulation mechanisms involved in biofilm reformation (membrane biofouling) after membrane chemical cleaning, which is of particular significance to the improvement of cleaning efficiency and application of membrane technologies.

Beschreibung: In the context of the management of bathing water quality, the intermittent contamination of rainwater drainage pumps (unconventional point sources) could be controlled by peracetic acid disinfection. Thus, a field experimental study was carried out to set up a water safety plan, determining the monitoring parameters and the critical limit for corrective actions. With a 0.5 mg/l dosage, the average logarithmic microbial reduction was 0.50 ± 0.48 for Escherichia coli (EC) and 0.43 ± 0.54 for intestinal enterococci. Among the chemical and physical parameters that could be monitored in real time, the oxidation–reduction potential was the only one able to predict the microbial concentration discharged from a drainage pump and the logarithmic abatement of EC. Considering the possible impact of this source on bathing waters in terms of additional risk of gastrointestinal infections, the critical limit for continuous monitoring was established using a quantitative microbial risk assessment (QMRA) model.

Beschreibung: To offer an alternative for supplying fresh water to people in distress in tropical seas before rescue or to garrison soldiers on a small reef, a portable solar-photovoltaic atmospheric water generator was designed and tested experimentally, and is composed of a water generating module, a water purifying module, a power supply and control module, and a buoyancy module. The results showed that the best water production rate of 460 mL/h was achieved when Tin = 27, RHin = 92%, Qa = 600 m3/h, with the desalination rate above 99.65%, proving itself a feasible solution as a portable desalination device. The daily water production can reach 5.52 L/d, which is more than twice the minimum quantity of the WHO drinking water standard (2.5 L/capita-day), and the energy consumption can be controlled under 200 W. The influences of major operating parameters on the device performance were analyzed and performance comparisons were carried out with the reported AWG products/prototypes. By integrating with a distress signal launcher and positioning module to shorten rescue time, the device has the potential to be employed as a small rescue platform for people in distress in tropical oceans, carried on board ship as a precaution.

Beschreibung: Activated carbon particle electrodes modified by oxygen or nitrogen groups could be promising electrode candidates for capacitive deionization (CDI) processes. In this work, activated carbon particle electrodes were modified by phosphoric acid, nitric acid, urea, melamine, and zinc chloride to enhance desalination of an aqueous electrolytic solution. The modified activated carbon particles were characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, Brunauer–Emmett–Teller measurements and electrochemical scanning. The electrodes with oxygen or nitrogen groups on the surface exhibited a much higher desalination capacity and charge efficiency than those without any surface modification. Particularly, the activated carbon particle electrode modified by phosphoric acid exhibited a desalination capacity of 15.52 mg/g at 1.4 V in 500 mg/L NaCl solution, which was approximately eight times that of the unmodified electrode (2.46 mg/g). The enhancement was attributed to a higher specific capacitance, a lower electrochemical impedance and an increase in oxygen or nitrogen-containing groups on the surface.

Beschreibung: Escherichia coli and other enteric pathogens presence indicate that the water has been contaminated with fecal matter. River deltas are population hotspots which are becoming increasingly urbanized and where poor sanitation has been frequently identified as a pressing issue. In this study, we have investigated the spatial distribution of E. coli in river deltas under varying river discharge, temperature and irradiation at the water surface. A hydrodynamic and water quality model has been used to reproduce an idealized river delta configuration and to investigate the spatial distribution of E. coli across the delta floodplain and channels. The concentration of E. coli rapidly declines downstream, following a tripartite trend with different decline rates on the delta front, pro-delta and shelf area. The highest differences in the spatial distribution of E. coli bacteria occur for low-river discharge values. Temperature and irradiation both influence the concentration of E. coli and mostly influence downstream areas and smaller channels.

Beschreibung: Sewer pipe networks are expected to operate with minimal or no interruptions. The complex nature of randomly occurring failures in sewer networks arising from blockages significantly adds to the cost of operation and maintenance. Blockages are significant due to sewage backup or basements flooding, resulting from their occurrence. Therefore, continuous performance assessment of sewer pipe networks is necessary to ensure required levels of service at an acceptable cost. This study provides insight into the performance of the sewer pipe networks by assessing the proneness of the network to blockages. Furthermore it draws inferences at a holistic strategic level of influential explanatory factors of blockage proneness, using data available in the Swedish Water and Wastewater Association's benchmarking system. Results indicate that medium sized municipalities are prone to at least 30% more blockages per km per year compared to other municipalities. A hypothesis of explanatory factors includes reduced flow volumes and flow depth. Flow velocities below self-cleaning velocity in sewer pipe networks, encouraged by sluggishness of flow are responsible for increased possibility for sediment deposition and accumulation in sewers leading to blockages. This is also exacerbated by the deposition of non-disposables (wet wipes, baby diapers, hard paper, etc.), accumulation of fats, oils and grease in sewers and increased water conservation measures.

Beschreibung: Craft beer is a rapidly growing market globally, placing an increased burden on wastewater treatment plants. To avoid discharge fees, new technology is required to make the on-site treatment of brewery wastewater affordable. This study assessed the application of a novel attached growth bioreactor (AGBR) to treat brewery wastewater to a discharge target (1,500 mg sCOD/L). Specifically, the impacts of the single-pass residence time (HRTsingle-pass), organic loading and media height were investigated. A HRTsingle-pass of 67 min demonstrated the shortest required time to meet the discharge target and the lowest final effluent concentration after 120 hr treatment time. Long HRTsingle-pass demonstrated slower biomass development, while smaller HRTsingle-pass caused an earlier rise in dissolved oxygen (DO) which hindered organic removal by heterotrophic bacteria. The sCOD removal rate increased with loading rates, however plateaued at 65 g sCOD/m2/day for loading rates above 300 g sCOD/m2/day. The media became flooded with biomass for feed strengths above 6.0 g sCOD/L. Greater media height provided additional surface area for biomass development, but marginally decreased the sCOD removal rate (g/m2/day) due to an earlier introduction of DO. Power consumption and footprint considerations found the greater media height to be the preferred choice for breweries.

Beschreibung: The Ganga is an international transboundary river that flows across three major riparian countries: India, Nepal, and Bangladesh, where India shares a significant proportion of the total basin area. The river system is highly dynamic and regularly floods in all three countries due to abundant rainfall in a short period of only four months each year that causes tremendous loss of both property and human life. In this study, we have done a synoptic review to synthesize the hydrology, hydrogeology, and modeling studies that have analyzed hydrological changes and their impacts in the Ganga basin. This review also identifies some of the knowledge gaps and discusses possible options for enhancing the understanding of sustainable water development and management. This review indicated that transparent data sharing, use of satellite-based observations along with in-situ data, integrated hydro-economic modeling linked to reliable coupled surface–groundwater models, a central shared decision support center for early warning systems to deal with hydrological extremes, joint river commissions and monitoring teams, and multilateral water sharing treaties (agreements) are required to promote sustainable and equitable distribution of water resources and to avoid water sharing conflicts in the Ganga basin.

Beschreibung: The federal research project, PAkmem, deals with the recycling of industrial wastewater. The aim of the project is to develop and pilot an innovative integrative process for produced water treatment in the oil and gas industry utilizing flotation and ceramic micro-nano-membrane filtrations (MF-NF membranes) as well as the wastewater treatment of the ceramic industry with ceramic NF-membranes and electrodialysis (ED). The process utilized should remove fine particles, organic matter and divalent ions in order to make the water dischargeable or reusable (direct disposal or reuse as process water in the ceramic industry and the enhanced oil recovery reinjection in the oil and gas industry in which the water is conditioned in order to increase the oil production yield). Three pilot plants were designed and built according to strict safety standards and were operated on industrial manufacturing sites in Germany in 2019. Two innovative optical fine particle measuring techniques (inline and online) have been specially adapted for the project and integrated into the pilot plants. The results show promising technical potential for the use of ceramic membranes in the above-mentioned applications.

Beschreibung: Advanced wastewater treatment is often used to produce one single water quality. In recent years, technologies have been developed that allow the production of different qualities that are fit for their purpose. These technology bundles are still not being marketed, and market requirements are unclear. Two constellations in West Basin, California and in Oman were analysed to shed light on the different constellations of actors, resource situations and institutions. The first led to the industrial reuse of several water qualities, while the second produced an application in holiday resorts, leisure and food production. A hypothetical solution was contrasted with an historical case. The analysis of the constellations showed that multi-sectoral investments and dependencies require strong cooperation arrangements and long-term agreements. Governmental institutions were revealed to be suitable for coordinating the process, especially during the initial phase, but also in view of security of supply. A (comparative) examination allows an initial, still provisional systematic overview of other constellations that favour systems with recycled water of different qualities. Further research is required to understand the welfare and distribution effects of multimodal water pricing policies and the feasibility of co-financing of agricultural irrigation and opportunities for more sustainable water reuse.

Beschreibung: Water infrastructure in cities is complex and requires proactive management to optimise function. The scale and distribution of assets across municipalities requires affordable systems which can trigger alerts. Systems underpinned by low-cost sensors could meet increasing monitoring needs: more assets, more often, and at a better resolution. However, low-cost sensors require appropriate testing to assess their performance and optimise their use. Here, we focus on low-cost water level sensors, often considered as the main monitoring parameters for water-related infrastructures. We developed a platform and testing protocol to assess the suitability of low-cost sensors. We assessed the performance of three widely used low-cost sensors: laser-ranging, ultrasonic-ranging, and pressure. Our main results showed that the ultrasonic sensor offers the best price to accuracy ratio, and the pressure sensor provides the highest accuracy while still at a very low cost. Our platform and protocol provide a standardised testing and calibration method which can be applied to any sensor. The platform can be used to gather and share results, to enhance community knowledge and encourage the use of new (low-cost or not) sensors. The development of low-cost sensors is an important step toward the wider use monitoring systems for water infrastructure.

Beschreibung: A shortage of safe drinking water is one of the leading problems in the world. Even in developed countries where water treatment systems are present, safe drinking water may not be always available due to the limitations of advanced water treatment techniques and high energy costs. On the other hand, many rural communities in Asia and Africa situated in semi-arid to arid regions are without reliable access to clean drinking water. It is, therefore, important to explore how solar energy can be linked to water treatment systems for clean drinking water production. Membrane-based water purification technologies play a major role in water purification by utilization of low-cost heat sources to make the process economically and technically viable for small, medium, and large-scale applications. Solar energy can be a viable source of power for water purification facilities in the coming years. Photovoltaic panels and solar thermal collectors are appropriate solar energy collectors for making a solar-powered water treatment system. Solar-assisted membrane-based water purification techniques could have a viable solution to the existing problems in semi-arid and arid regions. Due to the high quality of potable water demand, studies have been carried out on solar-assisted membrane-based technologies in water purification. This review considers basic concepts, specific energy consumption, water production cost, and applications of solar-driven membrane-based water purification technologies such as reverse osmosis, forward osmosis, electrodialysis, membrane distillation, and hybrid membrane systems. This review will allow the researchers to have a wider overview of the effort made by several investigators in the area of solar-assisted membrane-based water purification technology.

Beschreibung: Requirements for wastewater management and water-reuse concepts concerning sustainability are gaining greater importance, especially in times of climate change. Industrial park developments are often hindered due to water scarcity. Thus, nowadays, the reuse of wastewater is becoming more and more important to increase the availability of water and to enable new developments. The sustainable Industrial WasteWater Management Concept with the focus on Reuse (IW2MC → R) provides a solution strategy to produce reuse water from industrial wastewater within production plants. To achieve sustainability, certain requirements are essential since the reuse water can be provided directly via an optimized wastewater treatment process for subsequent use. Hence, it is then ‘fit for purpose’. This enables a more efficient application of reuse water. Furthermore, due to environmental issues, it is important to construct space-saving water resource recovery facilities for reducing land consumption within industrial parks.

Beschreibung: Catchment scale conceptual hydrological models apply calibration parameters entirely based on observed historical data in the climate change impact assessment. The study used the most advanced machine learning algorithms based on Ensemble Regression and Random Forest models to develop dynamically calibrated factors which can form as a basis for the analysis of hydrological responses under climate change. The Random Forest algorithm was identified as a robust method to model the calibration factors with limited data for training and testing with precipitation, evapotranspiration and uncalibrated runoff based on various performance measures. The developed model was further used to study the runoff response under climate change variability of precipitation and temperatures. A statistical downscaling model based on K-means clustering, Classification and Regression Trees and Support Vector Regression was used to develop the precipitation and temperature projections based on MIROC GCM outputs with the RCP 4.5 scenario. The proposed modelling framework has been demonstrated on a semi-arid river basin of peninsular India, Krishna River Basin (KRB). The basin outlet runoff was predicted to decrease (13.26%) for future scenarios under climate change due to an increase in temperature (0.6 °C) compared to a precipitation increase (13.12%) resulting in an overall reduction in water availability over KRB.

Beschreibung: Mining is usually associated with draining of large quantities of water. On the other hand, mining operations themselves are water users for purposes like coal or ore washing, dust mitigation, recultivation, etc. The normally existing water surplus can be seen as a resource for public purposes instead of discharging the water to rivers and the sea. It is typical for the mining operation that these water amounts vary spatio-temporally according to the mining process. The R&D project WaterMiner investigates the example of the Hon Gai hard coal mining area in Ha Long, Vietnam, as to how and to what extent under the variable spatio-temporal conditions the mine water can cover the water demand in the mines themselves and contribute to the public water supply in the surrounding settlement area of Hon Gai. The spatio-temporal change of mine water drainage, mine water treatment and mine-internal water use and the potential mine-external water use volumes in the project region are investigated by a material flow model and visualized by Sankey diagrams, maps, and tables. Several options for delivery of mine water for mine-external water uses as a contribution to the public water supply are shown.

Beschreibung: Landfill leachate is characterised by high chemical and biological oxygen demand and generally consists of undesirable substances such as organic and inorganic contaminants. Landfill leachate may differ depending on the content and age of landfill contents, the degradation procedure, climate and hydrological conditions. We aimed to explain the characteristics of landfill leachate and define the practicality of using different techniques for treating landfill leachate. Different treatments comprising biological methods (e.g. bioreactors, bioremediation and phytoremediation) and physicochemical approaches (e.g. advanced oxidation processes, adsorption, coagulation/flocculation and membrane filtration) were investigated in this study. Membrane bioreactors and integrated biological techniques, including integrated anaerobic ammonium oxidation and nitrification/denitrification processes, have demonstrated high performance in ammonia and nitrogen elimination, with a removal effectiveness of more than 90%. Moreover, improved elimination efficiency for suspended solids and turbidity has been achieved by coagulation/flocculation techniques. In addition, improved elimination of metals can be attained by combining different treatment techniques, with a removal effectiveness of 40–100%. Furthermore, combined treatment techniques for treating landfill leachate, owing to its high chemical oxygen demand and concentrations of ammonia and low biodegradability, have been reported with good performance. However, further study is necessary to enhance treatment methods to achieve maximum removal efficiency.

Beschreibung: In recent years, the use of solar energy has been growing exponentially and applied in a wider range of applications; one of the important applications for using solar energy is water desalination. The current work investigates the proof of concept experimental setup for a novel solar multi-effect distillation (MED) using alternate storage tanks. The experimental setup consists of a MED unit, two thermal storage tanks, and a solar collector. One storage tank is used as a charging tank while the other tank is used as a discharging tank. This unique dual-tank system stores the thermal energy to be used later in the MED unit, which improves the control of the water mass flow rate and water temperature throughout the MED process. The peak temperature achieved every day in the charging tank determines the MED production capacity. This system is designed for the tanks to alternate roles every 24 hours. The testing of this design was carried out during May 2019 in Saudi Arabia. The experimental results prove the novel concept design to work efficiently providing an average production rate of about 21 kg/day with total solar collector area of 2.7 m2 and average daily performance ratio of 2.5.

Beschreibung: Stormwater runoff is identified as a major source of pollution in water bodies, and to limit the impact of these pollutants on groundwater quality, permeable asphalt pavement systems (PAPS) have been built worldwide. But so far, few have considered zeolite or regulated zeolite as a post-treatment in reservoirs in PAPS. This study aimed at investigating the efficiencies of modified zeolites in removing NH4+-N and TP from stormwater runoff and providing a novel insight into the research on the reuse of stormwater runoff by PAPS. The effect of PAPS with a zeolite-regulated reservoir on removing nutrient in stormwater was explored by artificial rainfall experiments and temporary storage experiments. Results showed that the removal rate of NH4+-N and TP in PAPS with a regulated-zeolite reservoir increased by 23.7% and 37.2%, respectively, during simulated rainfall events when compared to those without a regulated-zeolite reservoir. TP was mainly removed by the form of phosphorus precipitation such as Zr(H2PO4)2. Ion exchange and adsorption during the temporary storage period were considered as the main approaches for removal of NH4+-N and TP. This study can help develop an optimal strategy for the operation of PAPS in treating stormwater runoff from urban roads.

Beschreibung: Rising water scarcity and abundant brine water resources, especially in desert locations, call for the wider adaptation of desalination techniques. Furthermore, the interdependency of water and energy has gained more attention in recent years and it is expected to play an important role in the near future. The present study deals with both topics in that it presents the coupling of a power plant with desalination units for the simultaneous generation of energy and water in Iran. The power plant used in the analysis is the Qom combined-cycle power plant. The plant is integrated, first, with a multi-stage flash (MSF) unit and, then, with a multi-effect desalination (MED) unit, and it is evaluated using energy and exergy analyses. We find that the generated power of the integrated systems is decreased by 9.7% and 8.5% with the MED and the MSF units, respectively. Lastly, the freshwater production in the plant using MED is significantly higher than in the plant with MSF (1,000 versus 1,521 kg/s).

Beschreibung: In the coming years, numerous regions are expected to suffer from water scarcity. One of the technologies of great interest in facing this challenge has been the generation of freshwater through water desalination, a process that reduces the amount of salt and minerals to a standard level, making the water suitable for drinking or agricultural/industrial use. The efficiency of each desalination process depends on the concentration of salts in the raw water and the end-use of the produced water. The present study presents the exergetic and exergoeconomic analyses of the coupling of a power plant with desalination units for the simultaneous generation of energy and water in Iran. The plant is integrated, first, with a multi-stage flash (MSF) unit and, then, with a multi-effect desalination (MED) unit. We find that the cost of exergy destruction of the MED and MSF integrated plants is lower when compared to the standalone power plant by about 0.1% and 9.2%, respectively. Lastly, the freshwater production in the plant using MED is significantly higher than that in the plant with MSF (1,000 versus 1,521 kg/s).

Beschreibung: In the circular economy system, the water sector is increasingly becoming a field of concrete experimentation and application on an industrial scale of techniques intended to save and produce energy and to produce materials from water treatment cycles. The water cycle itself represents a ‘circular economy system’ connected to the use of water resources and to the processes of recovery of ‘secondary’ resources, such as energy and raw materials. This paper aims to identify the measures that can be taken by the institutions responsible for regulating the sector to encourage operators to invest in the circular economy and to develop corporate policies based on environmental sustainability and efficiency. It describes: the main actions for the recovery of energy and matter in the management of the water cycle; the current configuration of the regulatory measures adopted in Italy by the Italian Regulatory Authority of Energy, Networks and the Environment (ARERA); and some future developments in regulation policies. The views expressed in this paper are those of the authors and do not necessarily represent those of ARERA.

Beschreibung: Dewatered municipal sludge was used as raw material to prepare activated carbon (SAC), and the SAC was modified by walnut shell and nano-titanium dioxide (MSAC). The results showed that the MSAC had a higher specific surface area (SBET) (279.147 m2/g) and total pore volume (VT) (0.324 cm3/g) than the SAC. Simultaneously, the functional groups such as C-O, C = O, and Ti-O-Ti on the surface of MSAC were enhanced due to modification. These physicochemical properties provided prerequisites for the diffusion and degradation of pollutants in MSAC. Furthermore, the MSAC was applied to adsorb amoxicillin (AMX) from aqueous solution, in batch experiments, the maximum removal rate (88.19%) was observed at an initial AMX concentration of 30 mg/L, MSAC dosage of 5.0 g/L, pH of 8, contact time of 180 min, and temperature of 25 °C. In addition, the adsorption process was well described by the Freundlich isotherm model and pseudo-second-order kinetic model, indicating that the adsorption of AMX onto MSAC was dominated by multilayer chemisorption. Also, the adsorption thermodynamics suggested that the adsorption process of AMX onto MSAC was endothermic, feasible and spontaneous.

Beschreibung: Classifying water quality irregularities in reverse osmosis (RO) production plants requires suitable systems to provide intelligent warnings to the operators or supervisors who are engaged in executing corrective procedures applicable to production. The suggested deep learning methods are of utmost importance to identify at once variations in water quality irregularities in plants through competent classification methods, thereby enabling a reduction of burden for operators. In this paper, two types of LSTM-CNN based classification techniques are suggested to classify water quality features temporally into grades based on corrective actions that classify irregularity conditions of water quality on the basis of corrections. Distinct control methods are used for experiment to find water quality irregularities from variables, namely, pH, TDS, ORP, and EC, which aim to assist the production line. This proposed method enables automatic diagnosis and warning system about water quality in RO plants. For classification, LSTM-CNN was trained with data recorded from eight plants of west and north parts of Chennai region. This research is meant to demonstrate particularly the top-level classification job for quality alerts. The features obtained from 4,096 time series array data using LSTM-CNNs achieved sensitivity to 97% and accuracy to 98%.

Beschreibung: High nitrate concentrations in wastewater treatment plant effluents and aquifers can challenge sequential biofiltration systems in preventing nitrite and gas formation in the sand bed, as well as to achieve the regulated limit value for nitrate in potable water reuse applications. This study investigates the introduction of electron donors in the form of organic fixed bed materials as an in-situ anoxic zone into sequential biofiltration systems. Laboratory batch and column tests with straw, soft wood, peat, polylactic acid (PLA), and polycaprolacton (PCL) revealed incomplete denitrification with a hydraulic retention time below 10 h, high organic carbon leaching, especially during the first three months, and gas accumulation within the filter bed. Therefore, ex-situ denitrification prior to oxic biofilters or in a defined side-stream treatment is recommended. No enhanced transformation of trace organic chemicals was observed under nitrate reducing conditions. Peat revealed a sorption potential for 5-methyl-benzotriazole, carbamazepine, benzotriazole, and metoprolol.

Beschreibung: Based on three pilot- and demonstration-scale projects investigating agricultural irrigation practices with reclaimed water, risks associated with these water reuse practices are highlighted and processes and strategies to minimize associated microbial risks were evaluated. A number of treatment processes and combinations were tested regarding their efficacy for pathogen removal, representing the biggest threat to the quality of products from reuse irrigation practices. In addition, the importance of regrowth potential and different methods for monitoring risks associated with pathogens were discussed. One method for online monitoring is flow cytometry. The results of an exemplary quantitative microbial risk assessment (QMRA) were discussed to determine the significance of microbial risks. Multi-barrier approaches comprised of technical and administrative barriers can reduce the risks of water reuse significantly. Quality management also needs to address all stakeholders involved in a reuse project, starting from source control in the sewershed to marketing of the final products. In addition, environmental risks of water reuse need to be addressed by quality management as well.

Beschreibung: An electrolysis (ELC) system was proposed to remove co-existing F−, Ca2+, Mg2+, CO32−, and HCO3− from groundwater without the addition of any chemicals. The proposed system utilized an ELC cell composed of non-corrosive platinum and stainless steel electrodes. Ion removal mechanisms, performance against different ion concentrations, and charge loading were studied and compared with drinking and industrial water quality guidelines. System performance with real groundwater was also examined. Results revealed that ELC effectively removes (CO32− + HCO3−) in the anode as CO2, and (CO32− + HCO3−), Ca2+, and Mg2+ in cathode as MgCO3, CaCO3, and Mg(OH)2. F− was removed by co-precipitation with Mg(OH)2 and Coulomb transfer. Maximum removal of 58%-F−, 42%-Ca2+, and 95%-Mg2+ were observed at a charge loading of 1500 C/L. With increasing Ca2+ and Mg2+, removal increments of cathode F−, Ca2+, Mg2+, and (CO32− + HCO3−) were noticed. To meet drinking water guidelines value of 1.5 mg/L of F−, minimum initial ion concentration ranges should be within F− 〈 4.29–6 mg/L, Mg2+ 〈 75–125 mg/L, Ca2+ > 50 mg/L, and (CO32− + HCO3−) 〈 10–0 mmol/L for 1500 C/L. The anode delivered the quality water which meets industrial boiler water alkalinity guideline for the initial (CO32− + HCO3−) 〈 12.5 meq/L. The community-scale treatment system established in Sri Lanka confirmed smooth operation with a higher removal of F− and Ca2+ in the cathode and (CO32− + HCO3−) in the anode which can be slightly approximated with laboratory results.

Beschreibung: Nitrate and organic contamination from Midwest rivers, including the White River at Muncie, IN, has been an on-going concern and contributes to the hypoxic zone in the Gulf. Despite rich data, recent water quality changes have rarely been investigated. This study employed 16 years of continuous monitoring data, including biochemical oxygen demand (BOD), dissolved oxygen (DO), and nitrate–nitrite as nitrogen (NN) from five sites near Muncie, and analyzed the water quality trend and pollution sources. A novel approach, Weighted Regression on Time, Discharge and Seasons that allows for the representation of long-term water quality patterns by considering seasonal variance and discharge-related effects over time, is adopted. Flow-normalized BOD and NN concentration and flux both increased, and DO concentration and flux decreased. However, the changes vary among sites. Muncie wastewater treatment plant and combined sewage outflows (CSOs) contribute remarkably to NN pollution during low-flow seasons. Urban and agricultural runoff, and CSOs impact BOD levels. Agricultural runoff contribution to BOD is increasing in recent years. Seasonal patterns of nitrate and BOD in the river are also analyzed. The results are helpful for watershed managers to re-think conservation practices and have indications to water quality management beyond the study area.

Beschreibung: The objective of this study is to assess the level of application of integrated water resources management (IWRM) in the lower Oueme valley. In order to achieve this, interviews with the actors' families allowed, on the basis of the survey on indicator 6.5.1 of the Sustainable Development Goals, to represent the degree of implementation of IWRM in the lower Oueme valley using a United Nations (UN) form. The results of this analysis reveal a low level of IWRM implementation with a score of 31 on a scale of 0–100. The weaknesses identified are mainly related to the lack of funding (score of 20/100) to cover all aspects of the development and management of water resources. Inadequate instruments or tools (score of 25/100) to enable decision-makers and users to make rational and informed decisions between different options and action measures, the unfavourable environment (score of 35/100) and finally weak institutional efficiency (score of 45/100), intersectoral coordination, and the involvement of various other stakeholders, are all evils that undermine the efficient management of water resources in the lower valley of Oueme.

Beschreibung: In this paper, a reliable treatment process for olive mill wastewaters (OMWW) is proposed. In order to develop a more sustainable process with polyphenols recovery and water reuse, two treatment schemes have been simulated by using a process simulator (SuperPro Designer®), depending on wastewater characteristics; the first applied for ‘biological’ effluents by using membrane technology (microfiltration MF, ultrafiltration UF, nanofiltration NF and reverse osmosis RO), the second for wastewaters containing pesticides, in which RO is replaced with an advanced oxidation process for pesticide degradation. The results of the process analysis showed that the final permeate is a treated water suitable for both disposal in aquatic receptors and for civil or agriculture reuse. Moreover, the results of a techno-economic analysis of the proposed processes is presented, carried out by means of a life cycle cost analysis, considering the mass and energy balances obtained from process analysis. The analysis showed that the first scenario is more economically feasible. In detail, the treatment cost (€/m3 of OMWW) was 253 and 292 €/m3 for the first and second case study, respectively. However, the second process scheme result is inappropriate if the wastewater to be treated does not come from biological olive processing.

Beschreibung: White adipose tissue (WAT) and brown adipose tissue (BAT) are involved in whole-body energy homeostasis and metabolic regulation. Changes to mass and function of these tissues impact glucose homeostasis and whole-body energy balance during development of obesity, weight loss, and subsequent weight regain. Omega-3 polyunsaturated fatty acids (ω-3 PUFAs), which have known hypotriglyceridemic and cardioprotective effects, can also impact WAT and BAT function. In rodent models, these fatty acids alleviate obesity-associated WAT inflammation, improve energy metabolism, and increase thermogenic markers in BAT. Emerging evidence suggests that ω-3 PUFAs can also modulate gut microbiota impacting WAT function and adiposity. This review discusses molecular mechanisms, implications of these findings, translation to humans, and future work, especially with reference to the potential of these fatty acids in weight loss maintenance.

Beschreibung: Epigenetic mechanisms play fundamental roles in regulating numerous biological processes in various developmental and environmental contexts. Three highly interconnected epigenetic control mechanisms, including small noncoding RNAs, DNA methylation, and histone modifications, contribute to the establishment of plant epigenetic profiles. During the past decade, a growing body of experimental work has revealed the intricate, diverse, and dynamic roles that epigenetic modifications play in plant–nematode interactions. In this review, I summarize recent progress regarding the functions of small RNAs in mediating plant responses to infection by cyst and root-knot nematodes, with a focus on the functions of microRNAs. I also recapitulate recent advances in genome-wide DNA methylation analysis and discuss how cyst nematodes induce extensive and dynamic changes in the plant methylome that impact the transcriptional activity of genes and transposable elements. Finally, the potential role of nematode effector proteins in triggering such epigenome changes is discussed.

Beschreibung: Land plants host a vast and diverse virome that is dominated by RNA viruses, with major additional contributions from reverse-transcribing and single-stranded (ss) DNA viruses. Here, we introduce the recently adopted comprehensive taxonomy of viruses based on phylogenomic analyses, as applied to the plant virome. We further trace the evolutionary ancestry of distinct plant virus lineages to primordial genetic mobile elements. We discuss the growing evidence of the pivotal role of horizontal virus transfer from invertebrates to plants during the terrestrialization of these organisms, which was enabled by the evolution of close ecological associations between these diverse organisms. It is our hope that the emerging big picture of the formation and global architecture of the plant virome will be of broad interest to plant biologists and virologists alike and will stimulate ever deeper inquiry into the fascinating field of virus–plant coevolution.

Beschreibung: Plant pathogens are a critical component of the microbiome that exist as populations undergoing ecological and evolutionary processes within their host. Many aspects of virulence rely on social interactions mediated through multiple forms of public goods, including quorum-sensing signals, exoenzymes, and effectors. Virulence and disease progression involve life-history decisions that have social implications with large effects on both host and microbe fitness, such as the timing of key transitions. Considering the molecular basis of sequential stages of plant–pathogen interactions highlights many opportunities for pathogens to cheat, and there is evidence for ample variation in virulence. Case studies reveal systems where cheating has been demonstrated and others where it is likely occurring. Harnessing the social interactions of pathogens, along with leveraging novel sensing and -omics technologies to understand microbial fitness in the field, will enable us to better manage plant microbiomes in the interest of plant health.

Beschreibung: Plant pathology must contribute to improving food security in a safe operating space, which is shrinking as a result of declining natural resources, climate change, and the growing world population. This review analyzes the position of plant pathology in a nexus of relationships, which is mapped and where the coupled dynamics of crop growth, disease, and yield losses are modeled. We derive a hierarchy of pathogens, whereby pathogens reducing radiation interception (RI), radiation use efficiency (RUE), and harvest index increasingly impact crop yields in the approximate proportions: 1:4.5:4,700. Since the dawn of agriculture, plant breeding has targeted the harvest index as a main objective for domesticated plants. Surprisingly, the literature suggests that pathogens that reduce yields by directly damaging harvestable plant tissues have received much less attention than those that reduce RI or RUE. Ecological disease management needs to target diverse production situations and therefore must consider variation in attainable yields; this can be achieved through the reengineering of agrosystems to incorporate built-in dynamic diversity of genes, plants, and crop stands.

Beschreibung: During the Cold War, coffee became a strategically important crop in the global contest between the United States and the Soviet Union. The economies of many US allies in Latin America depended upon coffee. In the Cold War context, then, the coffee leaf rust ( Hemileia vastatrix) became a geopolitical problem. Coffee experts in Latin America, which produced most of the world's coffee, began to prepare for an outbreak. In the 1950s, they built a global network of coffee experts. This network was sustained by US-led Cold War programs that promoted technical collaboration across the Global South, such as Harry Truman's Point Four programs. We explore the network's growth and evolution through one of its central figures, the American plant pathologist Frederick L. Wellman. This network has survived the end of the Cold War and evolved to reflect the new geopolitical context.

Beschreibung: The EDS1 family of structurally unique lipase-like proteins EDS1, SAG101, and PAD4 evolved in seed plants, on top of existing phytohormone and nucleotide-binding–leucine-rich-repeat (NLR) networks, to regulate immunity pathways against host-adapted biotrophic pathogens. Exclusive heterodimers between EDS1 and SAG101 or PAD4 create essential surfaces for resistance signaling. Phylogenomic information, together with functional studies in Arabidopsis and tobacco, identify a coevolved module between the EDS1–SAG101 heterodimer and coiled-coil (CC) HET-S and LOP-B (CCHELO) domain helper NLRs that is recruited by intracellular Toll-interleukin1-receptor (TIR) domain NLR receptors to confer host cell death and pathogen immunity. EDS1–PAD4 heterodimers have a different and broader activity in basal immunity that transcriptionally reinforces local and systemic defenses triggered by various NLRs. Here, we consider EDS1 family protein functions across seed plant lineages in the context of networking with receptor and helper NLRs and downstream resistance machineries. The different modes of action and pathway connectivities of EDS1 family members go some way to explaining their central role in biotic stress resilience.

Beschreibung: Detection, identification, and quantification of plant diseases by sensor techniques are expected to enable a more precise disease control, as sensors are sensitive, objective, and highly available for disease assessment. Recent progress in sensor technology and data processing is very promising; nevertheless, technical constraints and issues inherent to variability in host–pathogen interactions currently limit the use of sensors in various fields of application. The information from spectral [e.g., RGB (red, green, blue)], multispectral, and hyperspectral sensors that measure reflectance, fluorescence, and emission of radiation or from electronic noses that detect volatile organic compounds released from plants or pathogens, as well as the potential of sensors to characterize the health status of crops, is evaluated based on the recent literature. Phytopathological aspects of remote sensing of plant diseases across different scales and for various purposes are discussed, including spatial disease patterns, epidemic spread of pathogens, crop characteristics, and links to disease control. Future challenges in sensor use are identified.

Beschreibung: Plant pathogens have played an important role in weed biological control since the 1970s. So far, 36 fungal pathogens have been authorized for introduction across 18 countries for the classical biological control of weeds. Their safety record has been excellent, but questions continue to be asked about the risk that they could transfer to other plants. Quantitative data documenting their impact on the weed populations are still limited. Of the 15 bioherbicides based on living microorganisms that have ever been registered, only two were commercially available at the time of this review. The development and commercialization of bioherbicides in affluent countries are still plagued by technological hurdles and limited market potential. Not-for-profit small-scale production and distribution systems for bioherbicides in low-income countries may have potential as an inexpensive approach to controlling pervasive weeds. The types of research underpinning biological control approaches and challenges encountered are highlighted using specific examples.

Beschreibung: The significance of water scarcity to crop production and food security has been globally recognized as a pivotal sustainability challenge in the UN Sustainable Development Goals ( 86 ). The critical link between water scarcity and sustainability is adaptation. Various changes in water use practices have been employed to alleviate production constraints. However, the potential for these changes to influence crop diseases has received relatively little attention, despite the circumglobal importance of diseases to agricultural sustainability. This article reviews what is known about the realized effects of scarcity-driven alterations in water use practices on diseases in the field in order to raise awareness of the potential for both increased disease risk and possible beneficial effects on crop disease management. This is followed by consideration of the primary mechanistic drivers underlying disease outcomes under various water use adaptation scenarios, concluding with a vision for disease–water co-management options and future research needs.

Beschreibung: Increasing evidence indicates that tolerance is a host defense strategy against pathogens as widespread and successful as resistance. Since the concept of tolerance was proposed more than a century ago, it has been in continuous evolution. In parallel, our understanding of its mechanistic bases and its consequences for host and pathogen interactions, ecology, and evolution has grown. This review aims at summarizing the conceptual changes in the meaning of tolerance inside and outside the field of phytopathology, emphasizing difficulties in demonstrating and quantifying this trait. We also discuss evidence of tolerance and current knowledge on its genetic regulation, mechanisms, and role in host–pathogen coevolution, highlighting common patterns across hosts and pathogens. We hope that this comprehensive review attracts more plant pathologists to the study of this key plant defense response.

Beschreibung: Global change is pressing forest pathologists to solve increasingly complex problems. We argue that understanding interactive effects between forest pathogens and global warming, globalization, and land-use changes may benefit from a functional ecology mindset. Traits can be more informative about ecological functions than species inventories and may deliver a more mechanistic description of forest disease. Myriad microbes with pathogenic potential interact with forest ecosystems at different organizational levels. Elucidation of functional traits may enable the microbial complexity to be reduced into manageable categories with predictive power. In this review, we propose guidelines that allow the research community to develop a functional forest pathology approach. We suggest new angles by which functional questions can be used to resolve burning issues on tree disease. Building up functional databases for pathogenicity is key to implementing these approaches.

Beschreibung: Focusing on the discovery and characterization of the Arabidopsis disease resistance protein RPS5 and its guardee PBS1, this review discusses work done in the Innes laboratory from the initial identification of the RPS5 gene in 1995 to the recent deployment of the PBS1 decoy system in crops. This is done through discussion of the structure, function, and signaling environment of RPS5 and PBS1, highlighting collaborations and influential ideas along the way. RPS5, a nucleotide-binding leucine-rich repeat (NLR) protein, is activated by the proteolytic cleavage of PBS1. We have shown that the cleavage site within PBS1 can be altered to contain cleavage sites for other proteases, enabling RPS5 activation by these proteases, thereby conferring resistance to different pathogens. This decoy approach has since been translated into crop species using endogenous PBS1 orthologs and holds strong potential for GMO-free development of new genetic resistance against important crop pathogens.

Beschreibung: Gall-inducing insects and nematodes engage in sophisticated interactions with their host plants. These parasites can induce major morphological and physiological changes in host roots, leaves, and other tissues. Sedentary endoparasitic nematodes, root-knot and cyst nematodes in particular, as well as gall-inducing and leaf-mining insects, manipulate plant development to form unique organs that provide them with food from feeding cells. Sometimes, infected tissues may undergo a developmental switch resulting in the formation of aberrant and spectacular structures (clubs or galls). We describe here the complex interactions between these plant-reprogramming sedentary endoparasites and their infected hosts, focusing on similarities between strategies of plant manipulation. We highlight progress in our understanding of the host plant response to infection and focus on the nematode and insect molecules secreted in planta. We suggest thatlooking at similarities may identify convergent and conserved strategies and shed light on the promise they hold for the development of new management strategies in agriculture and forestry.

Beschreibung: The loss of methyl bromide as a soil fumigant and minimal advances in the development and registration of new chemical fumigants has resulted in a resurgence of interest in the application of organic amendments (OAs) for soilborne plant pathogen and plant-parasitic nematode management. Significant progress has been made in the characterization of OAs, application of strategies for their use, and elucidation of mechanisms by which they suppress soilborne pests. Nonetheless, their utility is limited by the variability of disease control, expense, and the logistics of introducing them into crop production systems. Recent advances in molecular techniques have led to significant progress in the elucidation of the role of bacteria and fungi and their metabolic products on disease suppression with the addition of OAs. Biosolarization and anaerobic soil disinfestation, developed to manipulate systems and favor beneficial microorganisms to maximize their impact on plant pathogens, are built on a strong historical research foundation in OAs and the physical, chemical, and biological characteristics of disease-suppressive soils. This review focuses on recent applications of OAs and their potential for the management of soilborne plant pathogens and plant-parasitic nematodes, with emphasis primarily on annual fruit and vegetable production systems.

Beschreibung: Non-native invasive plants can establish in natural areas, where they can be ecologically damaging and costly to manage. Like cultivated plants, invasive plants can experience a relatively disease-free period upon introduction and accumulate pathogens over time. Diseases of invasive plant populations are infrequently studied compared to diseases of agriculture, forestry, and even native plant populations. We evaluated similarities and differences in the processes that are likely to affect pathogen accumulation and disease in invasive plants compared to cultivated plants, which are the dominant focus of the field of plant pathology. Invasive plants experience more genetic, biotic, and abiotic variation across space and over time than cultivated plants, which is expected to stabilize the ecological and evolutionary dynamics of interactions with pathogens and possibly weaken the efficacy of infectious disease in their control. Although disease is expected to be context dependent, the widespread distribution of invasive plants makes them important pathogen reservoirs. Research on invasive plant diseases can both protect crops and help manage invasive plant populations.