Search

A formulated photocurable poly(ethylene glycol) diacrylate (PEGDA) and 2‐hydroxylethyl methacrylate (HEMA) polymer matrix (PEGDA:HEMA) was developed for constructing an adsorptive 3D cubic monolith using masked stereolithography (MSLA) 3D‐printing technique. A pure PEGDA formulation served as a control in comparative studies. Additionally, two structural designs (solid cube and cubic lattice) were also quantitatively compared to determine the adsorption performance for Rhodamine B (RhB) dye removal. Results indicated that the cubic lattice formulated with hydrophilic PEGDA:HEMA (θ~47.20°) was more effective at removing RhB dye. Additionally, the preliminary study identified pH 9 as the optimal level for RhB dye removal using 3D cubic monolith for both formulations. A Taguchi orthogonal array of L9 (33) was used to concurrently vary three parameters: adsorbent dosage (0.65 ± 0.02 g per cubic lattice), operating temperature (30°C, 40°C, and 50°C), and initial RhB concentration (20, 60, and 100 ppm). The highest mean of the signal‐to‐noise (S/N) ratio was chosen to obtain the highest adsorption performance. The removal efficiency (R%) of RhB dye ranged from 44.48% to 94.86%, and the adsorption capacity (K) ranged from 0.59 to 3.73 (mg/g) after 5 h. Seven adsorption isotherms and five adsorption kinetics modelling were performed. Adsorption isotherm data fitted well with the Redlich–Peterson model for both linear (R2 = 0.998) and nonlinear (R2 = 1). Besides that, the pseudo‐second‐order model (PSO) accurately described adsorption kinetics (R2 = 0.995). The separation factor (RL) confirmed favourable adsorption (0 < RL < 1). Thermodynamic parameters indicated that the adsorption process was endothermic and at higher temperatures, entropy increased. Also, the 3D–printed PEGDA:HEMA cubic lattice exhibited good mechanical stability. Furthermore, the 3D PEGA: HEMA lattice has the ability to be used in several adsorption cycles of degrading RhB dye. Ultimately, the present work demonstrates the viability of 3D printing photocurable PEGDA:HEMA resin and utilizes statistical tools to optimize process parameters, enhancing predictability for wastewater management. [ABSTRACT FROM AUTHOR]

TiO2 photocatalyst has the advantages of high catalytic activity, suitable energy band potential, high chemical stability, high photoelectric conversion efficiency, high safety and non-toxicity, which exhibits excellent performances in photocatalytic degradation of organic wastewater. However, it is difficult to separate and recover TiO2 photocatalyst from the reactive system. Interestingly, magnetic TiO2 prepared by combining TiO2 with superparamagnetic ferromagnetic particles can overcome this shortcoming. In this review, the preparation method and the photocatalytic mechanism of magnetic TiO2 were summarized. Moreover, the catalytic mechanisms of the modified binary, ternary and multicomponent magnetic TiO2 composite photocatalysts were compared, and the effects of different magnetic substrates on the degradation activity were discussed. Besides the applications in the wastewater treatment, the development trend and application prospects were prospected. [ABSTRACT FROM AUTHOR]

Wastewater has become the predominant treatment because of the high scarcity of water. Transition metal molybdates were broadly investigated in water treatment. To enhance the performance and reliability, rare earth molybdates were investigated. Herein, we report the preparation of novel Gd 2 MoO 6 nanoparticles with carbon composites, such as rGO and g-C 3 N 4 , employing hydrothermal technique and it was used as a photocatalyst for wastewater treatment. The rGO substance was substantiated by D- and G-bands in Raman studies. The morphology of the pure photocatalyst revealed a coral structure when rGO and g-C 3 N 4 were added, and a nanoplate-like structure was grown. rGO sheets were identified in TEM studies, and their crystallinity was confirmed by the SAED pattern. Basic dyes, azo dyes, and textile wastewater were treated with the prepared photocatalysts under visible light. The photocatalysts achieved good performance in reducing different classes of dyes. rGO-Gd 2 MoO 6 exhibited superior performance evaluated with other two photocatalysts. The efficiency of g–C 3 N 4 –Gd 2 MoO 6 is almost equal to that of rGO-Gd 2 MoO 6. The rate constant value attained for the rGO-Gd 2 MoO 6 on wastewater was 0.0176 min1. The quality of the wastewater was also improved after treatment. The superior activity of the carbon-composited Gd 2 MoO 6 was due to better generation and low recombination of e−/h+ pairs during photocatalysis. As rGO-Gd 2 MoO 6 exhibits superior performance under visible light, it can be a novel photocatalyst for practical wastewater management. [ABSTRACT FROM AUTHOR]

The increasing volume of wastewater discharged in urban areas poses a significant environmental challenge, particularly due to the potential for organic carbon overload in aquatic ecosystems. This study aimed to identify the bacterial isolates with the potential to mitigate this burden by effectively degrading organic matter and exhibiting antagonistic activity against common aquatic pathogens. Through a screening process, two bacterial strains, Bacillus amyloliquefaciens and Bacillus licheniformis, were isolated based on their high amylolytic, cellulolytic, proteolytic and lipolytic activity indices. In addition, in relation to all effective strains for these activities, Bacillus amyloliquefaciens differed in the cellulolytic index (4.48 ± 0.12), while Bacillus licheniformis had a lipolytic index of 1.73 ± 0.10. Both strains were further characterized by their strong antagonistic activity against Aeromonas, a prevalent pathogen in aquatic environments. These findings suggest that B. amyloliquefaciens and B. licheniformis hold promise as bioremediation agents for wastewater treatment, potentially contributing to the sustainable management of urban wastewater and the protection of aquatic ecosystems. [ABSTRACT FROM AUTHOR]

There is a common misconception that aquatic macrophytes face significant challenges in wetland-based sewage treatment systems. This study aims to correct this perception by focusing on the crucial morphophysiological adaptations of aquatic macrophytes that enable them to thrive in wetland-based sewage treatment systems, particularly under environmental stress. These adaptations are vital for improving the efficiency and resilience of wastewater treatment processes, offering sustainable solutions in the face of variable environmental conditions and complex contaminant mixtures. The review emphasizes the role of macrophytes as natural engineers, capable of enhancing pollutant removal and system stability through their unique structural and functional traits. By understanding these adaptations, the review aims to guide the optimization of wetland design and management, ultimately contributing to more sustainable and effective wastewater treatment practices. The findings underscore the importance of species selection and the integration of nature-based solutions in environmental management, advocating for policies that support the use of macrophytes in modern wastewater management. [ABSTRACT FROM AUTHOR]

The quest for sustainable agricultural practices has led to a surge in research focused on innovative wastewater treatment methods. This review explores the emerging biological treatment approaches designed to address the challenges of eco-friendly agricultural wastewater treatment and subsequent reuse. The investigation centers around three novel techniques: constructed wetlands, algae-based systems, and microbial fuel cells. Constructed wetlands (CWs) mimic natural processes to treat agricultural wastewater, providing habitat for various plant species that collaboratively remove contaminants. Algae-based systems(ABs) harness the photosynthetic prowess of algae to absorb nutrients and pollutants, producing biomass that can be repurposed. Meanwhile, microbial fuel cells (MFCs) employ microorganisms to break down organic matter in wastewater while generating electricity as a valuable byproduct. This review aims to provide insights into the potential of these biological treatment methods to revolutionize wastewater management in agriculture. By mitigating environmental impact, conserving water resources, and yielding reusable outputs, these techniques will offer a sustainable pathway towards addressing the pressing challenges of agricultural wastewater treatment and enhancing the overall ecological balance. [ABSTRACT FROM AUTHOR]

The present research aimed to explore the durability of MMO electrodes through electro-oxidation (EO) in purifying secondary treated actual sewage wastewater using batch and pilot-scale setups. The main aim is to inactivate bacteria in sewage treatment plants before they are released into the environment, thus contaminating water and soil. Process parameters such as current density (j), NaCl dose (n), and treatment time (t) were optimized using response surface methodology in a lab-scale EO reactor under batch conditions. The results showed that optimization of current density at 5.90 mA/cm2 and NaCl concentration at 1.31 g/L led to 93.90% of bacterial inactivation (Q1) within 8 min of treatment and 0.48 kWh/m3 energy consumption (Q2). Biological analysis was conducted to validate bacterial cell destruction and count coliform bacteria in the EO-treated sewage wastewater. XRD, cyclic voltammetry studies, and FE-SEM/EDS analysis were done to confirm the MMO anode's durability and stability after 100 recycles. The study prioritized bacterial inactivation along with organic matter degradation. Besides that, a small pilot-scale study on the actual sewage wastewater with a volume of 10–50 L was done in batch mode under previously optimized conditions to analyze the efficacy of the MMO anodes in terms of bacterial inactivation. [ABSTRACT FROM AUTHOR]

Wastewater affordability is a pressing concern in the US as the cost of collecting and treating wastewater continues to rise rapidly, and reports have revealed that millions of residents are experiencing a lack of equitable access to affordable wastewater management. The USEPA has established an affordability metric based on 2.5% of median household income (MHI) and affordability is typically interpreted as the monthly utility bill. However, this approach is not applicable to the 25% of US households that are not connected to networked sewer. This study developed the first statewide methodology for mapping wastewater affordability for users of both networked and onsite wastewater treatment systems (OWTS) based on USEPA guidelines. The methodology used local data from the Alabama Department of Environmental Management (ADEM), utilities, and the US Census Bureau. This article presents a novel methodology for quantifying water and wastewater affordability challenges for large geographical areas while maintaining the accuracy of small-spatial scale analysis. This study also incorporated income inequalities by using census tract-level household income data to estimate the number of households in Alabama with unaffordable wastewater access. This study revealed that wastewater access affordability challenges are more widespread than indicated by traditional MHI-based analysis and are likely affecting approximately 445,000 households in Alabama (23.7%). This study also showed that expansions in the available funding and types of eligible applicants for grant programs that subsidize OWTS capital costs could reduce OWTS affordability challenges eightfold. We propose using this methodology to quantify affordability challenges alongside a suite of approaches to address wastewater affordability in the US at the utility and household levels to preserve the human right to affordable sanitation. Practical Applications: Wastewater affordability is a key aspect of providing sustainable wastewater collection and treatment for US residents. The ongoing discussions about wastewater access affordability are often centered around customers of sewer utilities and neglect to consider the affordability challenges of residents with OWTS (commonly known as septic tank systems). This study develops a methodology for analyzing statewide wastewater access affordability for both residents with sewer bills and users of OWTS based on annual household incomes at the census tract level. This study reveals that wastewater affordability challenges affect both users of centralized sewer networks and OWTS including approximately 445,000 households in Alabama (23.7%). [ABSTRACT FROM AUTHOR]

Solar evaporators have demonstrated huge potential in sewage purification and clean water supply based on their cost‐effective and sustainable merits. However, it remains challenging to realize the stable purification of high‐concentration dye sewage over the long term. Here, by incorporating a heterojunction photocatalyst, a photothermal/catalytic integrated solar evaporator is conceived to stabilize the purification of high‐concentration dye sewage. It is composed of g‐C3N4@TiO2 heterojunction as the photocatalyst, carbon nanotubes (CNTs) as the photothermal materials, and polyvinyl alcohol (PVA) network as water transportation material. The high photocatalytic activity of heterojunction enables the g‐C3N4@TiO2/CNTs/PVA (CTCP) evaporator to photodegrade the accumulated dye molecules on its evaporation surface under light irradiation during purifying dye sewage. More remarkably, the integrated CTCP evaporator achieves a stable evaporation rate of 2.30 kg m−2 h−1 in 1 mg mL−1 RhB solution with continuous light irradiation for 100 h, exhibiting preeminent long‐term stability. With the capacities of long‐term stable and high‐rate purification of high‐concentration dye sewage, it is expected that this CTCP evaporator provides an effective alternative to treat high‐concentration dye sewage and has direct implications in engineering multifunctional solar evaporators for complex wastewater treatment. [ABSTRACT FROM AUTHOR]

Water scarcity and sanitation pose a critical global challenge worsened by population growth and the finite nature of freshwater resources. Despite the United Nations' Sustainable Development Goal 6 (SDG6) advocating for universal water and sanitation access, progress remains insufficient. Presently, approximately 50% of generated wastewater is released into the environment without adequate treatment, emphasizing the urgent need to address this issue. This article examines the socio‐economic and technical aspects of both centralized and decentralized wastewater treatment systems (DWTS) and assesses the environmental impact, spatial footprint, and energy usage across treatment technologies. An economic analysis underscores the cost advantages of DWTS, especially in sparsely populated regions. With modular designs, DWTS not only provides environmental and economic advantages but also enables water reuse. The research concludes that adopting DWTS is crucial in achieving SDG6 targets and ensuring universal access to safe sanitation, especially in low‐density and newly developed areas. This thorough investigation of wastewater management contributes to the ongoing dialogue on sustainable solutions amidst escalating global challenges of water scarcity and sanitation. [ABSTRACT FROM AUTHOR]

Biomedical waste (BMW), including hospital wastewater (HWW), poses significant risks to the environment, workplace health and safety, as well as public health. Therefore, the selection of treatment technologies for BMW should be chosen in that way so that the negative impact of BMW and HWW can be neutralized. Considering this, the current review focuses on emerging green technologies for BMW and laboratory wastewater treatment and management. Improper waste management practices in developing nations have given rise to several issues, such as the introduction of pharmaceutical residues that are released into the environment. Hence, the timely adaptation and application of environmentally friendly technologies in the health sector is crucial. This study compares various technologies such as incineration, autoclaving, plasma pyrolysis, chemical disinfection, and microwave treatment, in terms of their feasibility, operational costs, and efficiency for the treatment of solid BMW. The study suggested selecting BMW treatment technology as per the Best Available Technology (BAT) principles of autoclave and microwave. Further, the liquid BMW is also a threat to the environment and human health. Ozonation technology has shown a promising ability for the pretreatment of laboratory and hospital wastewater. [ABSTRACT FROM AUTHOR]

The investigation into the implementation and widespread adoption of oyster shell recycling methods aimed at restoring coastal ecosystems and enhancing water quality is currently limited. In this study, we investigated the utilization of oyster shell powder (OSP) as a cost-effective and environmentally sustainable method for treating high-fluoride-concentration wastewater, a byproduct of industrial processes. We conducted extensive laboratory testing to determine the optimal conditions for fluoride removal. This involved variations in OSP doses, particle sizes, and initial wastewater pH levels. The results of these tests showed that OSP achieved fluoride removal efficiencies exceeding 98% at an optimal dosage of 5 g/L. In addition, OSP effectively adjusted the wastewater pH from highly acidic (pH 2) to almost neutral (pH 6.87), demonstrating its effectiveness in real-world industrial wastewater treatment. OSP, derived from oyster shell waste, is rich in calcium carbonate and offers a novel approach to wastewater management by leveraging a natural waste product. This study demonstrates the potential of OSP as a waste management strategy and contributor to the circular economy by repurposing industrial byproducts. [ABSTRACT FROM AUTHOR]

With urbanization acceleration, ensuring urban water use security and sustainable water resource management has become a major global challenge. As a populous country, China faces increasingly severe challenges. Comprehensive and systematic urban wastewater treatment efficiency (UWTE) assessments constitute a prerequisite for addressing this problem. Based on 2011-2021 panel data of 30 Chinese provinces, the superefficiency SBM model was employed for UWTE measurement from national and regional perspectives. ArcGIS software and the Tobit model were adopted to analyse the spatial-temporal patterns and factors influencing UWTE. UWTE in most provinces generally exhibited a fluctuating upward trend, with an uneven east-high and west-low spatial distribution pattern. The decomposition results showed that the low UWTE in the eastern region was mainly constrained by scale efficiency, while in the central region, pure technical efficiency was the primary constraint. The shunt pipeline construction level, load rate, and wastewater treatment scale significantly positively impacted UWTE, while economic scale yielded a negative impact. It is recommended that the Chinese government adjust the outdated construction-without-operation model and implement differentiated wastewater treatment policies. It is necessary to vigorously promote rainwater and wastewater diversion pipeline construction, optimize and upgrade sewer networks and wastewater treatment facilities, and fully utilize scale effects. These findings provide insights for China and countries similar to China to facilitate efficient wastewater management practices. [ABSTRACT FROM AUTHOR]

Abstract\nNOVELTYThis study investigates the treatment of combined wastewater from Hattar Industrial Estate using Biofilm Wetlands (BW) planted with monoculture species: Eichhornia crassipes (EAC), Pistia stratiotes (WL), and Arundo donax (GR). Each species showed distinct capabilities in organic degradation, metal uptake, and pH stabilization. BW2, planted with EAC, achieved the highest total solids (TS) and total suspended solids (TSS) removal efficiencies of 66% and 65%, respectively. GR effectively reduced initial COD concentrations from 232 mg/L to 58.67 mg/L, while EAC and WL reached reductions to 72.78 mg/L and 70.67 mg/L, respectively. Overall, the plant efficiency ranking was EAC > GR > WL. These findings underscore the potential of these plant species in synergistic BW systems, highlighting their role as natural solutions for remediating complex industrial effluents. This research contributes to advancing eco-friendly wastewater treatment approaches, suggesting promising applications for sustainable practices in industrial contexts.RESEARCH HIGHLIGHTSThis research assessed the effectiveness of phytoremediation using Eichhornia crassipes, Pistia stratiotes, and Arundo donax for removing pollutants i.e. heavy metals (Cd, Pb, Ni, K, Ca, Mg, Na, Fe, Hg) nitrates, phosphates and sulfates from combined industrial wastewater of Hattar Industrial Estate Pakistan.It highlighted the potential of selected plant species’ as natural treatment systems, providing crucial insights into their efficiency.Findings contribute to understanding nature-based solutions for complex industrial effluents.This research assessed the effectiveness of phytoremediation using Eichhornia crassipes, Pistia stratiotes, and Arundo donax for removing pollutants i.e. heavy metals (Cd, Pb, Ni, K, Ca, Mg, Na, Fe, Hg) nitrates, phosphates and sulfates from combined industrial wastewater of Hattar Industrial Estate Pakistan.It highlighted the potential of selected plant species’ as natural treatment systems, providing crucial insights into their efficiency.Findings contribute to understanding nature-based solutions for complex industrial effluents.This study harnessed the potential of three macrophytes to tackle industrial effluents, marking their debut in wastewater treatment. By championing environmentally conscious practices, it underscores the need for effective industrial wastewater management while promoting greener and more sustainable approaches within the industrial sector. [ABSTRACT FROM AUTHOR]

This study developed a new system for removing antibiotics using UV/ZIF-67 (Co)-activated peroxymonosulfate. The presence of antibiotic organic pollutants in urban sewage presents a substantial challenge for sewage treatment technologies. Due to the persistent chemical stability of antibiotics, their low environmental concentrations, and their resistance to degradation, effectively removing residual antibiotics remains a significant issue in urban wastewater treatment. This study introduces an eco-friendly photocatalytic technology designed to enhance the removal of oxytetracycline (OTC) from municipal wastewater using a UV/ZIF-67 (Co)/PMS system. The results showed that compared with UV, UV/PMS, ZIF-67 (Co), ZIF-67 (Co)/PMS, and UV/ZIF-67 (Co) systems, the UV/ZIF-67 (Co)/PMS system had the highest OTC removal rate. When 10 mg ZIF-67 (Co) and 1 mM PMS were applied to 100 mL 30 mg/L OTC solution, the degradation efficiency reached 87.73% under 400 W ultraviolet light. Increasing the dosage of ZIF-67 (Co) and PMS can improve the removal rate of OTC, but the marginal benefit of additional dosage is reduced. The highest degradation efficiency was observed at weakly acidic pH, which may be due to potential damage to the internal structure of the catalyst and reduced performance under extreme pH conditions. The influence of chloride ions and nitrate ions on the reaction system is minimal, while bicarbonate ions exhibit a significant inhibitory effect on the removal of OTC. The UV/ZIF-67 (Co)/PMS system exhibits adaptability to various water sources, including tap water, Guitang River water, and pure water. The results of free radical identification indicate the presence of hydroxyl and sulfate groups in the UV/ZIF-67 (Co)/PMS system, both of which play important roles in the degradation of OTC. This study offers valuable insights and technical support for the green, efficient, and environmentally friendly removal of antibiotics from urban wastewater. [ABSTRACT FROM AUTHOR]

Aerobic granular sludge (AGS) is an emerging replacement for activated sludge for advanced and sustainable wastewater treatment. This study examined the beneficial effect of granular activated carbon (GAC) addition on AGS formation and sewage treatment in tropical climates. GAC shortened the start-up period for granulation by minimizing sludge washout. Ammonium was removed effectively through partial nitrification and denitritation. Enhanced biological phosphate removal was established with ~98% removal efficiencies. Improved granulation, enrichment of polyphosphateaccumulating organisms, and establishment of enhanced biological phosphate removal pathways in tropical climates recommend GAC addition as a simple and potential start-up strategy for AGS-based biological wastewater treatment. [ABSTRACT FROM AUTHOR]

The study investigates the feasibility and performance of an indigenously designed algal-bacterial biofilm reactor (ABR) for treating graywater in rural areas. Focusing on both treatment efficacy and sustainability, the research explored two key areas: optimizing the ABR for efficient graywater treatment and evaluating the use of readily available, low-cost materials for its construction. To achieve this, ABR was optimized to handle the specific characteristics of rural graywater, including potential seasonal variations in nutrient concentrations. The optimized ABR's adaptability was rigorously assessed across various operational modes--batch, fed-batch, and continuous--demonstrating consistent removal efficiencies for key pollutants (COD, nitrate-nitrogen, total dissolved phosphate, and total ammoniacal nitrogen) under changing conditions. The fiber supportbased ABR demonstrated significant pollutant removal from rural graywater: 81% COD reduction, 49.5% nitrate-nitrogen (NO3-N), 88.46% total dissolved phosphate (TDP), and 83.42% total ammoniacal nitrogen (TAN) in batch mode. Moreover, there was almost complete removal of total suspended solids (from 142 mg L-1 on Day 1 to 0 mg L-1 on Day 6) and total coliform (39,000 CFU mL-1 to 30 CFU mL-1). Notably, these removal efficiencies remained consistent across fed-batch (and continuous operation modes), showcasing the ABR's adaptability. This adaptability facilitated a significant increase in treatment capacity, scaling from 3 L treated in batch mode (6 days) to 40 L in fed-batch mode (12 days) and a continuous treatment rate of 20 L per day. Further enhancing the sustainability of this approach, the study successfully employed readily available natural materials like bamboo pipes and sheets for constructing the ABR. This innovative design resulted in a remarkable increase in biomass productivity (9.8 g m-2 day-1) compared to polypropylene fiber-based reactors (4.5 g m-2 day-1) with enhanced treatment potential for all the parameters in batch mode (77.7% COD removal, 86% NO3-N removal, 81% TDP removal, 92% TAN removal, and 100% removal of total coliforms). This is the first reported algae-bacterial biofilm system using bamboo for wastewater treatment, promoting local resource utilization and a bio-based sustainable approach for rural graywater treatment. [ABSTRACT FROM AUTHOR]

In Erbil City, municipal wastewater (MWW) is disposed directly without any treatment processes in the natural environment water body and in some places used for irrigation purposes. Untreated MWW causes problems for the environment, and people's health. Water quantity and quality variation produce complications for water sources in Erbil City, Kurdistan Region-Iraq. There is a lack of performing MWW management fundamentals in the area as well. This research aimed to study the MWW management in Erbil City, presenting water resource difficulties and bringing about suitable solutions for the water resource problems, and also to highlight the risk for the poor Management. MWW Data on Erbil municipal (EMWW) water quality parameters were collected and analyzed for the study period (four months), beginning in October 2022 and ending in March 2023. Twelve EMWW quality parameters were captured and tested in the Laboratory, arranged, and compared with MWW disposal criteria and local standards. The following MWW parameters include pH, electrical conductivity (EC), total dissolved salts (TDS), chloride (CL), total solids (TS), total alkalinity, total acidity, chemical oxygen demand (COD), and colour. The results showed that Erbil's MWW characteristics in terms of temperatures ranged between 11-23 °C and in turn, affected biological species activities. Maximum PH value was 7.7. Total alkalinity found in the range from 140 to 178 mg/l. Chloride concentration results showed for October was 62 mg/l and the maximum value was 80 mg/l in November due to the increment in temperature and evaporation. The range of the COD values of sewage water for five months was 246 -773 mg. Erbil's MWW's moderate to medium strength may be treated and utilized for landscaping, fountains, and irrigation, minimizing the need for fresh water from resources like wells and surface water in the Greater Zab River. [ABSTRACT FROM AUTHOR]

The current concept of wastewater management and treatment in the European Union complies with the requirements of Directive 91/271/EEC on urban wastewater treatment, established in 1991 with a primary focus on limiting excessive organic carbon, nitrogen, and phosphorus in treated water. At that time, the reuse of treated water was not considered. Not surprisingly, attempts were made to remove as much carbon as possible in the form of CO2. The removal of nitrogen compounds by denitrification results in the formation of N2, which is then released into the atmosphere. When removing phosphorus compounds, the aim is to incorporate as much phosphorus as possible from the water into the sludge of the wastewater. This also ignores the fact that treated water can be a very valuable resource. In regions, particularly those with advanced agriculture, where wastewater from treatment plants pollutes the environment, adopting an appropriate approach could address summer water shortages, reduce CO2 emissions into the air, and reduce reliance on artificial fertilisers. The key prerequisite for any use of treated wastewater is adequate microbiological purification and the absence of hazardous substances. This paper analyses the effluent characteristics of some examples of wastewater treatment plants along the Slovenian Adriatic coast, and evaluates the possibilities of reusing the treated water. The results are correlated with the wastewater treatment efficiency data from the town of Rovinj (Croatia), which provides the reuse of treated wastewater for municipal purposes. [ABSTRACT FROM AUTHOR]

Interactions between anammox bacteria and ammonium-oxidizing archaea, complete ammonia-oxidizing bacteria, and nitrate/nitrite-dependent anaerobic methane oxidizing microorganisms offer a novel approach for the supply of nitrite to anammox bacteria for nitrogen removal from low-ammonium wastewater. Advances in material science reveal that interactions between anammox bacteria and carbonaceous materials, such as graphene oxide, granular activated carbon, biochar, and various forms of iron, can enhance anammox activity and nitrogen removal. The discovery of the extracellular electron transfer capability of anammox bacteria suggests a promising energy-efficient method for nitrogen removal with simultaneous energy recovery. The intrinsic adaptation of marine anammox bacteria to saline conditions positions them as a key tool for treating saline wastewater streams. Anaerobic ammonium oxidation (anammox) is an energy-efficient method for nitrogen removal that opens the possibility for energy-neutral wastewater treatment. Research on anammox over the past decade has primarily focused on its implementation in domestic wastewater treatment. However, emerging studies are now expanding its use to novel biotechnological applications and wastewater treatment processes. This review highlights recent advances in the anammox field that aim to overcome conventional bottlenecks, and explores novel and niche-specific applications of the anammox process. Despite the promising results and potential of these advances, challenges persist for their real-world implementation. This underscores the need for a transition from laboratory achievements to practical, scalable solutions for wastewater treatment which mark the next crucial phase in the evolution of anammox research. [ABSTRACT FROM AUTHOR]

A collaborative analysis of constructed wetlands in Latin America and the Caribbean, published in Spanish, brought together insights from 10 different countries in the region. The collective reports focused on both subsurface and surface flow wetlands. Treatment targets included industrial and agricultural discharges, yet the emphasis was on the treatment of domestic wastewater as a pollutant, and a lack of sufficient municipal wastewater treatment infrastructure. Common macrophyte genera as well as unique species were highlighted for their potential contributions to treatment and ecological diversity. Finally, a growing body of legal frameworks for establishment and protection were reported. [ABSTRACT FROM AUTHOR]

The unplanned and rapid expansion of metropolitan areas reduces accessibility to existing and often outdated centralized water and wastewater systems. In this context, sanitation policies that focus exclusively on centralized systems become expensive and unfeasible. Using Q methodology, we identified three different social perspectives on onsite wastewater treatment systems (OWTS) in the metropolitan area of the Lerma Valley in northern Argentina. We focused our analysis on the legal, environmental, and technical aspects of onsite sanitation. The perspectives found were: 'OWTS have advantages', 'Hard path for sewerage', and 'Process before technology'. We describe the perspectives identified and we provide an analysis of their differences and similarities to discuss their possible policy implications for our study area and comparable regions in the country and beyond. [ABSTRACT FROM AUTHOR]

Phosphorus (P) discharge from anthropogenic sources, notably sewage effluent and agricultural runoff, significantly contributes to eutrophication in aquatic environments. Stringent regulations have heightened the need for effective P removal technologies in wastewater treatment processes. This paper provides a comprehensive review of current P removal methods, focusing on both biological and chemical approaches. Biological treatments discussed include enhanced biological P removal in activated sludge systems, biological trickling filters, biofilm reactors, and constructed wetlands. The efficiency of microbial absorption and novel biotechnological integrations, such as the use of microalgae and fungi, are also examined. Chemical treatments reviewed encompass the application of metal salts, advanced oxidation processes such as chlorination, ozonation, and the Fenton reaction, as well as emerging techniques including the Electro-Fenton process and photocatalysis. Analytical methods for P, including spectrophotometric techniques and fractionation analyses, are evaluated to understand the dynamics of P in wastewater. This review critically assesses the strengths and limitations of each method, aiming to identify the most effective and sustainable solutions for P management in wastewater treatment. The integration of innovative strategies and advanced technologies is emphasized as crucial for optimizing P removal and ensuring compliance with environmental regulations. [ABSTRACT FROM AUTHOR]

The article discusses the importance of water, wastewater, and waste management for sustainable development. It emphasizes the need for innovative and effective solutions to improve the quality of life and maintain ecosystem balance. The article presents a special issue titled "Water, Wastewater and Waste Management for Sustainable Development," which covers various topics related to sustainable water and waste management in agriculture, waste and wastewater management, and the industrial sector. The special issue includes papers that explore topics such as the reuse of treated slaughterhouse wastewater for hydroponics, anaerobic digestion for biomethane production, evaluation of pollutant discharge in tomato hydroponic wastewater, and the impact of different cultivation methods on stream water quality. The article concludes by highlighting the importance of research and inviting further scientific activity in this area. [Extracted from the article]

In recent decades, the rising wastewater output from industrial pollution has inflicted severe harm on both surface and groundwater, leading to substantial environmental damage. The elimination of harmful, toxic materials and wastewater remediation are pressing global concerns and pose a formidable challenge for scientists worldwide. Heterogeneous photocatalysis has been recognized as a promising, effective, energy-free, and eco-friendly process capable of completely degrading various organic pollutants. Finding a material that simultaneously satisfies various thermodynamic and kinetic criteria, coupled with good thermal- and photo-stability, is a challenging task necessitating the modification of existing materials or the synthesis of new ones to meet the required standards. This present study comprehensibly elaborates on different approaches to the modification of various photocatalytic systems, both organic and inorganic, in order to obtain more efficient and feasible catalysts for practical applications. In addition, the current status of the application of photocatalysts in dye wastewater treatment is summarized, projecting the future direction for wastewater management by photocatalytic processes. [ABSTRACT FROM AUTHOR]

The partial nitritation (PN)–anammox (PN/A) process offers a sustainable alternative to nitrogen management in wastewater treatment, addressing the high costs and increasing the low eco-friendliness associated with traditional nitrification/denitrification processes. Stable partial nitritation (PN) is critical for effective PN/A operation, and this study specifically focused on the need to suppress nitrite-oxidizing bacteria (NOB) to facilitate the enrichment of ammonia-oxidizing bacteria (AOB). Utilizing two sequencing batch reactors (SBRs), PN1 and PN2 with different free ammonia (FA) concentrations, this study aimed to evaluate the NOB suppression strategy while enriching AOB. The PN2 reactor, which operated with a higher initial FA concentration (50 mg/L), successfully maintained high nitritation activity, with 96.1% ammonium removal efficiency (ARE) and 95.1% nitrite accumulation efficiency (NAE) at reduced influent NH4+-N concentrations (50 mg NH4+-N/L, FA 10 mg/L). In contrast, PN1 showed inadequate NOB suppression due to lower FA concentrations (10 mg/L). These results suggest that initiating the nitritation process with higher FA concentrations can effectively suppress NOB, enhancing the stability and efficiency of PN/A processes in mainstream applications. [ABSTRACT FROM AUTHOR]

The present work investigates the performance of a biofilm reactor filled with a new type of combined packing used to treat wastewater and explores a new technology approach for the application of coral sand and waste non-woven fabric. The combined packing was made of coral sand and waste non-woven fabric, which was used as a biofilm carrier to treat sewage. The experimental results showed that the removal efficiencies of COD, NH4+-N and TN in the biofilm reactor containing the combined packing were 92.9%, 72.9% and 63.2%, respectively. The maximum removal efficiencies of COD, NH4+-N and TN in the biofilm reactor containing single packing were 89.0%, 63.4% and 55.2%, respectively. The properties of the combined packing were characterized by Fourier Transform Infrared (FTIR), specific surface area, SEM and dehydrogenase activity. Infrared analysis showed that there were hydroxyl, carboxyl and carbonyl groups on the surface of coral sand and non-woven fabric which were beneficial for biofilm growth and wastewater treatment. The large pores in the interior of coral sand and non-woven fabric could provide a comfortable environment for microbes to grow and reproduce. The dehydrogenase activity of the biofilm on the surface of coral sand in the third biofilm reactor was 49.91 μgTF·g−1·h−1, which was significantly higher than that of the other two biofilm reactors. The new type of combined packing is suitable for biofilm carriers with low cost, which can be applied to actual sewage treatment projects. This study provides a reference for the practical application of the technique. [ABSTRACT FROM AUTHOR]

Constructed wetlands (CWs) have been widely recognised for efficiently removing many pollutants from wastewater, making them vital for environmental bioremediation. The substrates used in constructed wetlands are crucial in determining their overall performance, notably their ability to improve nitrogen and phosphorus removal from wastewater. This study aims to investigate the possibility of removing pollutants from wastewater using a pilot scale vertical flow constructed wetland (VFCW) planted with Phragmites australis applied to various substrates, such as gravel and sand in an arid climate in Southeast Algeria. The study involved using four basins, filled with sand and gravel. Two were planted with Phragmites australis and the others were left as a control without vegetation. The efficiency of the filtration systems was evaluated based on various physicochemical and organic parameters. Results showed that the highest hydraulic retention time is in the 7 days. The removal efficiency values are 84.38% for biological oxygen demand (DBO5), 77.45% for chemical oxygen demand (COD), and 83.30% for total solid matter (TSS) in the planted gravel filter. The planted sand filter had even higher removal efficiency values, with 89.59%, 85.80%, and 86.63% for DBO5, COD, and TSS, respectively. Nitrate concentration increased in all filters due to the complete transformation of ammonium into nitrate. NO2 -, NH4 +, and PO4 3-removal efficiencies were also higher in the planted sand filter 74.45%, 95.43%, and 77.64%, respectively. [ABSTRACT FROM AUTHOR]

This study presents a comprehensive investigation into the efficacy of advanced oxidation treatment methods, focusing on the photo-Fenton process for removing organic pollutants from wastewater. Despite prior research, significant knowledge gaps persist regarding the optimal operational conditions for maximizing pollutant removal efficiency. This manuscript fills those gaps through extensive batch experiments, meticulously evaluating the impacts of irradiation time, pH levels, and ferrous sulfate and hydrogen peroxide concentrations on treatment outcomes. Our results indicate that an irradiation time of 140 minutes and a pH of 3.1 are critical for achieving remarkable pollutant removal efficiencies: 91.57% for color, 85.14% for chemical oxygen demand (COD), and 79.87% for total organic carbon (TOC) over a 180-minute treatment period with optimal dosages. To further enhance understanding, we employed predictive models utilizing response surface methodology (RSM) and central composite design (CCD), rigorously assessing their statistical performance. The models demonstrated strong alignment with experimental data and existing literature, showcasing their reliability. This research not only provides novel insights into optimizing wastewater treatment processes but also holds significant practical value for industries aiming to implement effective strategies for mitigating organic pollution. By addressing critical knowledge gaps, this study lays a foundation for improved environmental remediation practices, offering a vital framework for industries committed to sustainable wastewater management. [ABSTRACT FROM AUTHOR]

Underground wastewater treatment plants (U-WWTPs) have emerged as a novel paradigm for urban wastewater pollutants management, offering benefits such as alleviating the Not-in-my-backyard (NIMBY) effect and utilizing land resources efficiently. China stands at the forefront, witnessing swift advancements in U-WWTP technology and deployment. However, the absence of a thorough understanding of their geographical distribution and operational characteristics could lead to misaligned planning and construction, resulting in inefficient resource allocation and treatment capacities for urban wastewater treatment. This dataset provides an up-to-date overview of the spatial distribution, process selection, and discharge standards for all U-WWTPs in China (with a total number of 201) constructed since 1995. To enhance comparative analysis, the dataset has been supplemented with information on conventional aboveground wastewater treatment plants (A-WWTPs), comprising a total of 2464 records, which enriches a more comprehensive evaluation of different wastewater treatment approaches. Utilizing this dataset can provide essential data support for the strategic management of urban wastewater systems and serve as a valuable reference for the paradigmatic renovation of existing wastewater treatment plants. [ABSTRACT FROM AUTHOR]

The widespread use of organophosphorus flame retardants (OPFRs) in industrial and household products increases the risk of their environmental exposure, posing a serious threat to ecosystems and human health. Photocatalytic technology has been widely used in wastewater treatment due to its high efficiency, mild reaction conditions, and robustness. This review summarizes the current status of research on photocatalytic degradation of OPFRs, focusing on the effect of different types of catalysts on the degradation efficiency, the effects of pH, and co-existing inorganic and organic ions. And pH and co-existing inorganic mainly affect the active oxygen and the active surface sites of the catalyst. In addition, toxicological calculations of the intermediates of the degradation pathway using T.E.S.T. and ECOSAR showed that photocatalysis could effectively reduce the toxicity of OPFRs. Development of new photocatalytic materials, in-depth study of the degradation mechanism of different catalysts and flame retardants, and attention to practical applications and toxicity issues can be the development direction of future research. [ABSTRACT FROM AUTHOR]

Bacteria of the Thiothrix morphotype, comprising the genera Thiothrix, Thiolinea and Thiofilum, are frequently encountered in domestic and industrial wastewater treatment systems, but they are usually not clearly differentiated due to the marked similarity in their morphologies. Methods ranging from light microscopy, FISH and PCR to modern high-throughput sequencing are used to identify them. The development of these bacteria in wastewater treatment systems has both advantages and disadvantages. On the one hand, the explosive growth of these bacteria can lead to activated sludge bulking or clogging of the treatment system's membranes, with a consequent decrease in the water treatment efficiency. On the other hand, members of the Thiothrix morphotype can improve the quality of granular sludge and increase the water treatment efficiency. This may be due to their capacity for sulfide oxidation, denitrification combined with the oxidation of reduced sulfur compounds, enhanced biological phosphate removal and possibly denitrifying phosphate removal. The recently obtained pangenome of the genus Thiothrix allows the explanation, at the genomic level, of the experimental results of various studies. Moreover, this review summarizes the data on the factors affecting the proliferation of representatives of the Thiothrix morphotype. [ABSTRACT FROM AUTHOR]

Johkasou systems have emerged as quintessential examples of decentralized wastewater treatment technologies due to their compact design, easy operation, and robust resistance to mechanical impact attributes that are particularly effective in mitigating and treating rural domestic wastewater. Although the efficiency of the Johkasou process in removing nitrogen and phosphorus has been well-documented, a comprehensive synthesis of the underlying mechanisms and influencing factors is still elusive. This review seeks to elucidate these aspects by detailing the biogeochemical pathways involved in nitrogen and phosphorus removal, characterizing the key microbial consortia, and addressing the potential accumulation of nitrous oxide (N2O). Furthermore, the review critically examines the impact of various media used in Johkasou systems on nutrient removal efficacy, with a particular emphasis on nitrogen. It also proposes a range of practical adjustments to design parameters, including dissolved oxygen (DO), pH, temperature, and hydraulic retention time (HRT), to enhance process performance. Finally, the practical implementation of Johkasou systems and their integration with ancillary processes in actual domestic sewage treatment scenarios are synthesized, providing a theoretical foundation for advancing Johkasou methodologies in rural areas. [ABSTRACT FROM AUTHOR]

Wastewater treatment plants generate significant amounts of sludge, a residual product that is rich in nutrients, usually considered waste, and traditionally eliminated by storage or incineration, methods that are expensive, environmentally damaging, and often unsustainable. Composting is increasingly recognized as an ecological and durable solution for managing biodegradable waste, including sludge resulting from wastewater treatment. The composting of residual sludge usually requires mixing with bulking agents, such as green waste or agricultural residues, to ensure a well-balanced carbon–nitrogen ratio. This mixture undergoes a controlled aerobic decomposition, sometimes followed by post-treatment, resulting in a stabilized final product that is nutrient-rich and pathogen-free and can be used as soil amendment or fertilizer in different agricultural or landscaping applications. By using composting, communities can reduce elimination costs, reduce greenhouse gas emissions, and minimize the environmental impact of sludge management. This paper reviews recent reported experiences in the laboratory regarding full-scale sludge composting, highlighting the particularities of the processes, the influence factors, the quality of the final product, and the environmental and regulatory constraints. Composting is a sustainable and ecological solution for managing wastewater sludge, contributing to nutrient circularity, and minimizing the environmental impact. [ABSTRACT FROM AUTHOR]

Land application of anaerobic digestion (AD) effluent as a fertilizer is desirable for nutrient recycling, but often supplies excess phosphorus (P), which contributes to surface water eutrophication. Reducing the P content in AD effluent filtrate using calcium (Ca) treatment prior to land application is a potential strategy for improving effluent disposal and meeting the discharge standard. This study took flue gas desulphurization (FGD) gypsum, a by-product of coal-fired power plants, as a low-cost Ca source, and combined with traditional phosphorus removal agents to achieve high phosphorus removal efficiency with less chemical cost. As the results showed, FGD gypsum dosages of 20 mmol/L Ca (3.44 g/L) and 40 mmol/L Ca (6.89 g/L) removed up to 97.1% of soluble P (initially 102.8 mg/L) within 60-90 minutes. Combining FGD gypsum treatment with traditional chemical treatments using calcium hydroxide [Ca(OH)2] or ferric chloride (FeCl3) could achieve >99% P removal with reduced chemical costs. This study demonstrated that FGD gypsum is an efficient calcium-based precipitant for phosphorus removal, offering a cost-effective and sustainable approach to enhance wastewater treatment practices and meet discharge standards in wastewater management. [ABSTRACT FROM AUTHOR]

Simple Summary: This study examines the use of dairy wastewater to cultivate three types of microalgae: Spirulina platensis, Micractinium, and Chlorella. The research found that these algae can effectively remove nutrients like nitrogen and phosphorus from industrial wastewater. Spirulina sp. and a mixed culture of all three algae performed best, significantly reducing nitrogen levels, while Chlorella sp. also removed a substantial amount of phosphorus. Additionally, microalgae treatment greatly reduced pathogens. These results suggest that microalgae could be a promising method for treating dairy wastewater and improving water quality. This study explores the novel use of mixed cultures of microalgae—Spirulina platensis, Micractinium, and Chlorella—for nutrient removal from dairy wastewater (DW). Microalgae were isolated from a local wastewater treatment plant and cultivated under various light conditions. The results showed significant biomass production, with mixed cultures achieving the highest biomass (2.51 g/L), followed by Spirulina (1.98 g/L) and Chlorella (1.92 g/L). Supplementing DW (75%) with BG medium (25%) significantly enhanced biomass and pH levels, improving pathogenic bacteria removal. Spirulina and mixed cultures exhibited high nitrogen removal efficiencies of 92.56% and 93.34%, respectively, while Chlorella achieved 86.85% nitrogen and 83.45% phosphorus removal. Although growth rates were lower under phosphorus-limited conditions, the microalgae adapted well to real DW, which is essential for effective algal harvesting. Phosphorus removal efficiencies ranged from 69.56% to 86.67%, with mixed cultures achieving the highest removal. Microbial and coliform removal efficiencies reached 97.81%, with elevated pH levels contributing to significant reductions in fecal E. coli and coliform levels. These findings suggest that integrating microalgae cultivation into DW treatment systems can significantly enhance nutrient and pathogen removal, providing a sustainable solution for wastewater management. [ABSTRACT FROM AUTHOR]

In light of the immense pressure population increase and urbanization are putting on freshwater resources, wastewater recycling and reuse have received more attention in recent years. However, in most developing countries, the available infrastructure is not adequate for efficient wastewater recycling and reuse. In this study, the Indian wastewater scenario was assessed in depth to elicit insights into managing wastewater challenges in developing countries. Sewage generation increased proportionately with the increasing urban population for the last 2 decades in India. The treatment capacity, however, could not keep pace with sewage generation, and currently, only 50% of urban sewage is being treated through centralized facilities. The same is the case with most prominent developing nations. Additionally, data show that the number of non-operational plants is increasing. The compliance rate of existing treatment facilities is meager in most Indian states, making the reuse of wastewater harder. Most other developing countries are likely to be operating under similar conditions. Having identified challenges in wastewater management for developing countries, this study further discusses some data gaps that need attention and the importance of closing these knowledge gaps in the context of decentralized treatment and reuse of wastewater. Furthermore, it discusses interventions and recommendations that can help overcome the identified challenges. [ABSTRACT FROM AUTHOR]

Filtration is one of the oldest techniques and by far the most widely applied in water treatment operations. It is considered one of the most effective methods for purifying waste water. Sand filtration consists of passing water loaded with suspended and colloidal matter through a filtering material in order to clarify it. In Ouargla region, wastewater is evacuated in a closed system without any treatment, which presents a natural risk to public health and endangers the sustainability of agriculture and the environment. In this modest study, two sand samples of different grain size and shape were used as the filter bed. Several filters were constructed using two types of sand with the same dimensions and different characteristics. The filter was exposed to clogging during the operation, which is prejudicial to the filtration process. For this reason, our study aims to see the influence of the type of sand on this process and analyze the phenomenon of filter clogging: the causes of its appearance, its types and their location as well as the parameters governing it. The most important thing is to evaluate the quantity of organic matter deposited in the different layers of the filter, and see its distribution as a function of time over the whole the depth of the filters. This study shows that the sand filter is subjected to progressive clogging. This clogging is classified into three fragments: mechanical, physical and organic. The study showed that the finer the granulometry, the greater the accumulation of organic matter. From the third week onwards, the formation of a biological film has been observed, which allows for very thorough purification. In other words, a quantity of suspended matter settles as the biomass degrades the organic matter. [ABSTRACT FROM AUTHOR]

As global urbanisation, industrialisation, and population growth escalate, the production of wastewater also increases, leading to significant water pollution on a global scale. This pollution poses severe threats to environmental health, wildlife, and human communities. In rural areas where centralised sewage systems are often absent, septic tanks play a crucial role in managing wastewater. They separate solids from liquids and facilitate the biological decomposition of organic matter. This paper utilises a Patent Landscape Review (PLR) to analyse the scope and direction of innovations in septic tank technology. Conducted on 23 September 2022, the patent search targeted filings from January 2001 through June 2022 to identify prevailing trends and advancements within this field. Through a detailed examination of 889 patents, categorised by keywords, processes, materials, and designs, this study offers a comprehensive overview of the patent landscape for septic tanks. Key findings indicate that fibreglass cylindrical tanks dominate the market due to their durability and efficiency. This review also highlights a growing trend towards modular septic systems, which offer scalable solutions adaptable to specific environmental conditions. Furthermore, some patents propose the repurposing of various objects as septic tanks, demonstrating a move towards sustainability by reducing waste and enhancing environmental conservation. This paper emphasises the importance of continued innovation in septic tank technology to address the challenges of effective wastewater management in underserved rural communities. [ABSTRACT FROM AUTHOR]

This review critically evaluates the algal–bacterial consortium (ABC) as a promising technology for wastewater treatment, carbon capture and storage, while also assessing its challenges and opportunities. The ABC system, characterized by the coupling of algae and bacteria, not only removes pollutants and reclaims resources but also helps in reducing greenhouse gas emissions. This system harnesses algal photosynthesis and bacterial degradation of organic matters to establish a carbon cycle, enhancing biomass production and pollutant removal. Despite its promise, the ABC process is subject to several hurdles, including sensitivity to low temperatures, reliance on artificial illumination, and the potential for algal biomass contamination by toxic substances. To capitalize on its full potential, continued research and technological advancements are imperative. Future investigations should focus on optimizing the system's operational efficiency, developing precise process models, exploring avenues for resource recovery, and broadening the scope of its applications. By surmounting these challenges, the ABC system has the capacity to make a significant impact on sustainable wastewater management and carbon fixation. [ABSTRACT FROM AUTHOR]

This year-long research analyzed emerging risks in influent, effluent wastewaters and biosolids from six wastewater treatment plants in Spain's Valencian Region. Specifically, it focused on human enteric and respiratory viruses, bacterial and viral faecal contamination indicators, extended-spectrum beta-lactamases-producing Escherichia coli, and antibiotic-resistance genes. Additionally, particles and microplastics in biosolid and wastewater samples were assessed. Human enteric viruses were prevalent in influent wastewater, with limited post-treatment reduction. Wastewater treatment effectively eliminated respiratory viruses, except for low levels of SARS-CoV-2 in effluent and biosolid samples, suggesting minimal public health risk. Antibiotic resistance genes and microplastics were persistently found in effluent and biosolids, thus indicating treatment inefficiencies and potential environmental dissemination. This multifaced research sheds light on diverse contaminants present after water reclamation, emphasizing the interconnectedness of human, animal, and environmental health in wastewater management. It underscores the need for a One Health approach to address the United Nations Sustainable Development Goals. [ABSTRACT FROM AUTHOR]

[Objective] The purpose of this paper is to study the optimal operation condition of AAO-MBBR mode of the new rural sewage treatment process and its treatment effect on pollutants. [Method] By comparing the pollutant removal rate under different residence time, different internal circulation ratio and different aerobic tank dissolved oxygen concentration, the optimal operation parameters of the equipment were screened out, and the equipment was set to operate under the optimal operating condition. The treatment effect on various pollutants was analyzed. [Result] The results showed that the improved AAO-MBBR process had the best removal effect when the hydraulic retention time was 8 h, the internal circulation ratio was 300% and the concentration of dissolved oxygen in aerobic pool was 2.5 mg/L. Under optimal operating conditions, the removal rates of SS, COD, BOD, NH3-N and TP of the equipment were 80%, 85%, 91%, 84.5% and 46%, respectively. And the treatment effect is significantly higher than that of other sewage treatment equipment. [Conclusion]The improved AAO-MBBR process has a good effect on pollutant removal in integrated wastewater treatment equipment. [ABSTRACT FROM AUTHOR]

Recently, membrane bioreactors (MBRs) have emerged as a promising approach for sewage treatment because of their high efficiency in removing contaminants. However, they are prone to membrane-fouling and computational loading. To resolve these issues, this research article presents an innovative control strategy combining both artificial bee colony optimization (ABC) and recurrent neural network (RNN) to regulate the performance of MBR in sewage treatment. Initially, the influent wastewater data were collected and pre-processed using the regression imputation approach. RNN architecture was designed and trained using the pre-processed data to forecast the performance of the MBN system. Further, the ABC algorithm was applied to optimize the function of MBR by adjusting the control variables. The developed model was validated with the publically available wastewater treatment plan dataset and the effectiveness of the developed model was validated by performing intensive performance and comparative assessment. The performance evaluation demonstrates that the proposed methodology attained greater results of 98.59% effluent quality, 98.70% of nutrient removal efficiency, less computational time of 2.87 s, and a low membrane-fouling index of 1.23%. The comparative analysis illustrates that the presented approach achieved improved performances than the existing methodologies. [ABSTRACT FROM AUTHOR]

Microbial flocculants (MBFs), a class of eco-friendly and biodegradable biopolymers produced by various microorganisms, have gained increasing attention as promising alternatives to conventional chemical flocculants in wastewater treatment and pollutant removal. This review presents a comprehensive overview of the current state of MBF research, encompassing their diverse sources (bacteria, fungi, and algae), major categories (polysaccharides, proteins, and glycoproteins), production processes, and flocculation performance and mechanisms. The wide-ranging applications of MBFs in removing suspended solids, heavy metals, dyes, and other pollutants from industrial and municipal wastewater are critically examined, highlighting their superior efficiency, selectivity, and environmental compatibility compared to traditional flocculants. Nonetheless, bioflocculants face significant challenges including high substrate costs, low production yields, and intricate purification methodologies, factors that impede their industrial scalability. Moreover, the risk of microbial contamination and the attendant health implications associated with the use of microbial flocculants (MBFs) necessitate thorough evaluation. To address the challenges of high production costs and variable product quality, strategies such as waste valorization, strain improvement, process optimization, and biosafety evaluation are discussed. Moreover, the development of multifunctional MBF-based flocculants and their synergistic use with other treatment technologies are identified as emerging trends for enhanced wastewater treatment and resource recovery. Future research directions are outlined, emphasizing the need for in-depth mechanistic studies, advanced characterization techniques, pilot-scale demonstrations to accelerate the industrial adoption of MBF, and moreover, integration with novel wastewater treatment processes, such as partial nitrification and the anammox process. This review is intended to inspire and guide further research and development efforts aimed at unlocking the full potential of MBFs as sustainable, high-performance, and cost-effective bioflocculants for addressing the escalating challenges in wastewater management and environmental conservation. [ABSTRACT FROM AUTHOR]

Wastewater output has increased considerably as a result of global population growth. Efforts to manage wastewater are expanding globally. Bio-based methods are useful and effective for treating a wide range of wastewaters, especially those from homes. In this research, the gray water stream at Sari Agricultural College in the north of Iran was treated using an anaerobic biological method. The purpose of this study was to determine whether using treated gray water for landscape irrigation was feasible or not. A fine screening pre-treatment system and a septic tank system were created in order to achieve this goal. After the first stage screening of superfluous solid components, anaerobic digestion was carried out for 26 hours at a temperature of between 14 and 16 °C in a 5 m³ septic tank. Treatment method function was revealed by measuring and comparing the pollutant indices with the permissible rates. The obtained data were: BOD of 19.5 mg/L, COD of 185 mg/L, suspended solid (SS) 90 mg/L, organic matter (OM) 80 mg/L, NO3 26 mg/L, PO4-3 of 6.25 mg/L, oil and grease (O&G) of 9.3%, pH of 5.9-7.1. The permissible rates for these indices are 100, 200, 200, 300, 30, 6.75, 10, and 6.8-7.1, respectively. The treated gray water was allowed to be utilized as irrigation water. After irrigating, the landscape did not face any negative effects. Nonetheless, the high acidity was owing to the detergents in effluent and this was the main reason provides a vast range of microelements leading to poisoning plants in a long period. [ABSTRACT FROM AUTHOR]

Rural decentralized domestic wastewater treatment (DDWT) facilities, as an alternative to centralized sewage treatment plants, have been rapidly developed in rural areas worldwide. However, the lack of performance evaluations and operational status assessments of these facilities poses a significant obstacle to advancements in rural domestic wastewater treatment strategies. In the present study, 30 rural DDWT facilities with AO (anoxic/oxic) and AAO (anaerobic/anoxic/oxic) processes were investigated. The results revealed that only two facilities reached the first A-grade discharge standards of China, and twelve facilities met the first B-grade discharge standards for all ten wastewater quality indicators. Low standard-achieving ratios for biochemical oxygen demand (BOD5) (63.3%), total nitrogen (TN) (60.0%), ammonia nitrogen (NH3-N) (63.3%), total phosphorus (TP) (30.0%), suspended solids (SS) (46.7%), and fecal coliforms (FC) (26.7%) were calculated. Thus, it is essential to improve the treatment efficiency for BOD5, TN, NH3-N, TP, SS, and FC for rural wastewater treatment facilities. In addition, the AAO process had a median weighted average removal efficiency of 82.02%, which was better than that of the AO process (72.48%). Minor equipment failure rates, i.e., less than 20%, did not affect the operation of the rural DDWT facilities, since most equipment in the DDWT facilities was backed up. Notably, problems in several areas, e.g., process design, equipment selection, construction, and especially operations, influencing treatment performance should be investigated and proactively addressed. These findings provide specific suggestions for improvements that could benefit the long-term operation and management of rural DDWT facilities. [ABSTRACT FROM AUTHOR]

Mercury pollution is a serious public health problem. China's extensive use and reliance on mercury has led to water pollution, particularly the presence of methylmercury in water. Estimating total mercury emissions from wastewater in China is challenging due to the large amount and wide range of emissions. An estimation model for total mercury content in sewage in China was established by establishing a relationship between sewage treatment volume, mercury content in effluent after sewage treatment, and the data of sludge production and mercury content in the sewage treatment plant. It was determined that only 3% of mercury entered the air during sewage treatment, 27.5% of mercury entered the effluent, and about 69.5% of mercury entered the sludge, based on the treatment of existing wastewater treatment plants in China. From 2002 to 2021, the average annual sewage mercury emission in China was 32.07 Mg, and the emissions were higher in densely populated and economically developed provinces such as Beijing, Shandong, Hebei, and Guangdong. By 2025, China's mercury emissions are projected to reach 55.41 Mg. By 2035, China's mercury emissions are projected to reach 49.3 Mg. [ABSTRACT FROM AUTHOR]

The 2030 Agenda, established in 2015, contains seventeen Sustainable Development Goals (SDGs) aimed at addressing global challenges. SDG-06, focused on clean water, drives the increase in basic sanitation coverage, the management of wastewater discharges, and water quality. Wastewater treatment could contribute to achieving 11 of the 17 SDGs. For this purpose, phytoremediation is a low-cost and adaptable alternative to the reduction and control of aquatic pollutants. The objective of this study is to highlight the role of macrophytes in the removal and degradation of these compounds, focusing on Eichhornia crassipes (Mart.) Solms, commonly known as water hyacinth. The reported values indicate that this plant has a removal capacity of over 70% for metals such as copper, aluminum, lead, mercury, cadmium, and metalloids such as arsenic. Additionally, it significantly improves water quality parameters such as turbidity, suspended solids, pH, dissolved oxygen, and color. It also reduces the presence of phosphates, and nitrogen compounds to values below 50%. It also plays a significant role in the removal of organic contaminants such as pesticides, pharmaceuticals, and dyes. This study describes several valuable by-products from the biomass of the water hyacinth, including animal and fish feed, energy generation (such as briquettes), ethanol, biogas, and composting. According to the analysis carried out, E. crassipes has a great capacity for phytoremediation, which makes it a viable solution for wastewater management, with great potential for water ecosystem restoration. [ABSTRACT FROM AUTHOR]