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Polymeric composite materials are in great demand in biomedical and water treatment applications. This is because they possess distinct characteristics and can fulfill specific biomedical needs, in addition to their ability to degrade dyes. This study successfully synthesized sustainable strontium titanate (STO) particles with an average size of 120 nm using the solid-state method. When these STO particles were mixed into a PCL-based polyurethane matrix, the matrix became hydrophilic with a contact angle of 58.60° and its mechanical strength enhanced by 320%. The morphology and surface roughness of the films were determined using FESEM and AFM techniques. The antibacterial studies of polymeric composites film against E. coli, Klebsiella pneumonia, and S. aureus , showing good zone growth, and showing enhanced swelling properties of 270% for wound healing and biomedical applications. The photocatalytic performance of the STO by degrading Methyl Orange (MO) and Congo Red (CR) under UV light, achieving degradation efficiencies of 92.25% for MO and 62.5% for CR over 150 min. These findings suggest that PU scaffolds and STO are suitable for biological and water treatment in industrial applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Pollution from organic molecules is a major environmental issue that needs to be addressed because of the negative impacts of both the harmfulness of the molecule structures and the toxicity that can spread through natural media. This is mainly due to their unavoidable partial oxidation under exposure to air and solar radiation into diverse derivatives. Even when insoluble, the latter can be dispersed in aqueous media through solvatation and/or complexation with soluble species. Coagulation–flocculation, biological water treatments or adsorption on solids cannot result in a total elimination of organic pollutants. Chemical degradation by chlorine and/or oxygen-based oxidizing agents is not a viable approach due to incomplete mineralization into carbon dioxide and other oxides. A more judicious strategy resides in mimicking natural oxidation under ambient conditions. Soils and aqueous clay suspensions are known to display adsorptive and catalytic properties, and slow and complete self-regeneration can be achieved in an optimum time frame with a much slower pollution throughput. A deep knowledge of the behavior of aluminosilicates and of oxidizing species in soils and aquatic media allows us to gain an understanding of their roles in natural oxidative processes. Their individual and combined contributions will be discussed in the present critical analysis of the reported literature. [ABSTRACT FROM AUTHOR]

In southwest Florida, the Caloosahatchee River flows from Lake Okeechobee into a biologically productive tidal estuarine system. A combination of excess water during the wet season, insufficient fresh water in the dry season, and poor quality of the river water are damaging the estuarine ecosystem. To better control the quality and quantity of the water entering the estuary, reservoirs are being constructed to store excess, poor quality water during the wet season and return it to the river for discharge into the estuary at an appropriate time. This stored water is enriched in nutrients and organic carbon. Because of the subtropical nature of the climate in southwest Florida and potential increases in temperature in the future, the return flow of water from the reservoirs must be treated before it can be returned to the river. Hence, an experimental water treatment system was developed and operated to compare biological treatment processes consisting of solely wetland plants versus adding some engineered processes, including slow sand filtration and a combination of slow sand filtration and ultraviolet (UV) treatment. These three treatment trains were operated and monitored through a seasonal cycle in 2021–2022. All three treatment methods significantly reduced the concentrations of nutrients and total organic carbon. While the enhanced engineered wetlands' treatment trains did slightly outperform the wetland train, a comparison of the three process trains showed no statistically significant difference. It was concluded that upscaling of the slow sand filtration and UV process could improve the treatment efficiency, but this change would have to be evaluated within a framework of long-term economic benefits. It was also concluded that the Caloosahatchee River water quality is quite enriched in nutrients so that reservoir storage would increase the organic carbon concentrations, making it imperative that it be treated before being returned to the river. It was also discovered that the green alga Cladophora sp. grew rapidly in the biological treatment tubs and will present a significant challenge for the treatment of the reservoir discharge water using the currently proposed alum treatment. [ABSTRACT FROM AUTHOR]

Aeration is crucial for the biological decomposition of organic compounds in wastewater treatment. However, it is a highly energy-intensive process in traditional activated sludge systems, accounting for 50% to 75% of a plant's electricity consumption and making it a major cost driver for wastewater treatment plants. Nanobubbles (NBs), characterized by their tiny size with diameters less than 200 nm, have emerged as a potential alternative to the low efficiency of aeration and high sludge production in aeration systems. NBs proved effective in removing COD and other pollutants from wastewater. For example, when applied in flotation, aeration, and advanced oxidation, NBs achieved up to 95%, 85%, and 92.5% COD removal, respectively. Considering the recent advancements in wastewater treatment, a compelling need arises for a thorough investigation of the effectiveness and mechanisms of nanobubbles in this field. This systematic review summarizes recent advancements in understanding nanobubbles (NBs) and their unique properties that enhance physical, chemical, and biological water and wastewater treatment processes. Moreover, this study reviews various methods for generating NBs and provides an in-depth review of their applications in wastewater treatment, with a particular focus on poultry slaughterhouse wastewater (PSW) treatment. [ABSTRACT FROM AUTHOR]

The waste of biological treatment plants in hospitals includes many pathological microbes, the rollout of which leads to problems for both the environment and the general health of organisms This study seeks to use environmentally friendly methods to tackle microbial pollution from hospital biologic treatment facilities in Basrah Govenoraten, and to use Elias' (Myrtus communis) paper extract as an antibacterial agent. Disc diffusion method has been used to determine a different concentration efficiency of Elias plant leaf extract as an antibacterial agent. The study's findings revealed the efficacy of alcoholic and aqueous extracts of Myrtus communis at various concentrations (12.5, 25, and 50 mg/mL) in eradicating pathogenic bacteria isolated from these treatment facilities. The bacteria included Staphylococcus lentus and Staphylococcus xylosus, as well as Sphingomonas paucimobilis, Escherichia coli Klebsiella oxytoca and Serratia ficaria, all of which have Gram-positive and Gram-negative bacterial profiles. The diameter of the inhibition zones was used to measure the effectiveness of the extracts, which ranged from 5 to 11 mm. The efficacy of plant extracts against each type of bacteria was greatly influenced by the type of extract used. Inhibition zones in the water extract were observed to be between 5 and 11 mm, with a greater activity against Gram-negative bacteria. Conversely, the alcohol extract showed inhibition zones that were 5 to 9 mm wide, with greater efficacy against Gram-positive bacteria. Based on these findings, it can be concluded that the Myrtus communis plant extract is an environmentally friendly method for addressing microbial pollution that originates from hospitals. [ABSTRACT FROM AUTHOR]

An attempt has been made to assess the performance of the third expansion of the Al-Rustamiya wastewater treatment plant (WWTP). This plant serves approximately 1,500,000 people in east Baghdad city, the capital of Iraq, and the increase of the population in this part of the city has reached about 4 million which led to deterioration in their effluents quality. Furthermore, the plant has no improvement on their processing units. Al-Rustamiya WWTP uses a biological water treatment method known as the activated sludge process with an average wastewater treatment of about 300 million liters. In the present paper, a wastewater quality data of ten years has been subjected to a multivariate statistical technique to identify the most important factors that affect the performance of the plant and estimating its efficiency. The data was collected and examined by the central laboratory of the Al-Rustamiya wastewater treatment plant in the mayoralty of Baghdad. Factor Analysis has been used to assess the important water quality parameters: pH, Total Suspended Solids, Biochemical Oxygen Demand (BOD), and Chemical Oxygen Demand (COD). The results revealed that the major factor that affects the performance is the organic load of raw wastewater and the removal efficiency of the WWTP. Furthermore, the results present that the performance of the current plant system is acceptable exclude for the removal efficiency of BOD below the prescribed limit. As well as, The BOD and COD correlation can evaluate wastewater treatment plant efficiency, aid in prompt intervention, and monitor harmful substances. [ABSTRACT FROM AUTHOR]

Electrochemical water treatment for recirculating aquaculture systems (RAS) is a promising approach for replacing the biological water treatment methods and establishing a new RAS generation with improved cost‐effectiveness, lower environmental footprint, and no start‐up periods. On top of ammonia oxidation directly into N2(g), electrochemical oxidation results in effective disinfection, and in the removal of organic matter, including specific organic constituents such as off‐flavour agents. The paper provides an overview of incentives for the implementation of electrochemical methods in RAS. It covers the electrochemical principles relevant to aquaculture applications, the effects of physical and chemical parameters, as well as design considerations. In addition, the research performed to date for integrating electrochemical methods in RAS operation is reviewed and the variety of designs and operational configurations described. The electrochemical water treatment is perceived beneficial over biological water treatment especially in cold saline‐seawater aquaculture (e.g., Atlantic salmon), where large nitrification reactors are required and the large water consumption for purging processes can be curtailed. It is also beneficial for the culturing of nitrate‐sensitive species (e.g., L. vannamei). The paper points out the gaps to be overcome for allowing commercial breakthroughs based on electrochemical water treatment, including the need for expanding the practice and improving engineering practices by operating pilot systems for growing fish at both small and large scales; adjusting of electrochemical cell designs for reducing both capital and operational costs; developing full‐proof malfunction‐free dechlorination strategies, and evaluating and optimizing the disinfection abilities for inactivating typical pathogens in aquaculture. [ABSTRACT FROM AUTHOR]

Rice milling involves shelling and polishing paddy grains to produce rice- both raw and parboiled. Parboiled rice production requires a massive quantity of freshwater for soaking, which, in turn, generates a large amount of wastewater. If this wastewater is not properly ameliorated, it can cause tremendous troubles of surface water pollution, land pollution, and, ultimately, groundwater pollution. Therefore, proper treatment of polluted water from rice mills (PWRM) as per the effluent discharge norms is necessary to protect the surface and subsurface water resources for sustainable development. There are two methods for remediating rice mill wastewater- physicochemical and biological. The biological methods produce comparatively less sludge and are cost-effective. Moreover, these processes are capable of retrieving green energy in the form of biomethane, biohydrogen, and bioelectricity to augment bio-fuel production, aiming to meet the ever-increasing fuel demands caused by rapid industrialization, motorization, and urbanization. The focus on green energy production is gaining momentum day by day due to the adverse effects of conventional energy derived from fossil fuel combustion in terms of enhanced Air Pollution Index (API) in the ambient atmosphere. In this paper, anaerobic biodegradation, phytoremediation, phyco-remediation, and microbial fuel cell techniques adopted by various researchers for remediating the polluted water from rice mills have been well addressed and critically discussed. The pros and cons of these biological methods have been well addressed to assess the socio-technoeconomic feasibility of each method. [ABSTRACT FROM AUTHOR]

A two-stage anaerobic-aerobic sequencing reactor system was developed in order to enhance the removal of biological phosphorus in the sequencing of combined reactors. Combining both aerobic and anaerobic designs in one reactor improved the efficiency and reduced the construction and operating costs. The combination of an upflow anaerobic fixed bed (UAFB) and a floating activated sludge aerobic bioreactor was designed with respective Kaldnes packing ratios of 90 and 30% for the anaerobic and aerobic sections. The controlled parameters were pH levels within a neutral range, a temperature of 37°C, mixed liquor suspended solids (MLSS) of 1220 and 1030 mg/L for the aerobic and anaerobic sections, respectively, and an attached growth that was equal of 743 and 1190 mg/L for the aerobic and anaerobic sections, respectively. Tests were conducted for three different initial phosphorus concentrations (12.8, 32.0, and 44.8 mg/L), two different volumes for each section, and four chemical oxygen demands (CODs) (500, 1000, 1200, and 1400 mg/L). The results demonstrated that, generally, the phosphorus removal in the anaerobic section fell significantly by increasing the inlet COD, and the maximum removal occurred at COD = 500 mg/L. More than 90% of the phosphorus was removed in the aerobic section at COD = 500 mg/L. In other words, the best performance of the reactor was when the ratio of the COD : N : P = 100 : 5 : 2, composition of phosphorus in industrial wastewater. [ABSTRACT FROM AUTHOR]

The study was conducted in 2017-2019 at the experimental field of the Institute of Irrigated Agriculture of NAAS (now the Institute of Climate-Smart Agriculture of the National Academy of Agrarian Sciences of Ukraine). Factor A studied different maturity groups of corn hybrids selected by the Institute of Irrigated Agriculture of the NAAS:Stepovyi, Skadovskyi, Inhulskyi, Chonhar, Arabat. Factor B - protection system: control, water treatment; biological; chemical; integrated. The highest conditionally net profit and profitability of hybrids of all FAO groups was observed under the integrated method of plant protection. The maximum value of conditional net profit is 2.26 and 3.26 thousand euro ha-1 was observed in mid-late hybrids Chonhar (FAO 420) and Arabat (FAO 430) under integrated plant protection systems. The mid-late Arabat hybrid (FAO 430) showed the maximum level of profitability of 117-141%. It is most economically profitable to grow mid-late hybrids Chonhar (FAO 420) and Arabat (FAO 430) under systems of integrated plant protection. [ABSTRACT FROM AUTHOR]

Phytoremediation is an economical technique for the biological treatment of soil and water contamination. Improving the growth of plants used in this technique leads to greater efficiency of the process. Herein, Lemna minor plant used in phytoremediation was collected from Sarab-e Nilufar region of Kermanshah province, Iran, and maintained in a culture medium. This study focused on the preparation of Ormus solution based on crystalline salt extracted from the salt mountains of Karmowstaj region in Fars province, Iran, to increase the proliferation of Lemna minor. The optimal growth conditions, including the pH of the medium, the residence time in the Ormus preparation process, and the concentration of Ormus solution were analyzed using the response surface methodology (RSM) based on a Box-Behnken design (BBD) model. Numerical optimization based on the quadratic model was carried out to achieve the maximum growth percentage. The percentage of the proliferation of Lemna minor varied from 34.6% to 117.3%, while growth was highest at a medium pH value of 10.75, a residence time of 72 h in the Ormus preparation process, and an Ormus concentration of 17 g.L−1. The results revealed that Ormus, as a supplemental fertilizer, under optimal conditions can significantly increase the rate of plant reproduction. Herein, the Ormus solution was applied for the first time to increase plant growth. In addition, the operating factors, including the pH of the medium, the residence time in the Ormus preparation process, and the concentration of Ormus solution, were optimized using the RSM based on a BBD model. In this study, Ormus was introduced under optimal conditions as a suitable additive to increase the proliferation rate of plants. [ABSTRACT FROM AUTHOR]

Natural swimming ponds using treatment wetlands (TWs) as an element of treatment of swimming water are an ecologically beneficial alternative to conventional pools. Unlike conventional swimming pools, in natural swimming ponds, the water treatment avoids the use of chemical methods and is based on the phenomenon of water self-purification and the rhizofiltration capacity of repository macrophytes in TWs of the regeneration zone, as well as on typical physical filtering processes (e.g., straining, sedimentation, or flotation), physicochemical filtration (physical and chemical adsorption, mainly of phosphorus), and biological filtration (nitrification and denitrification). Market solutions usually arise from the implementation of water treatment solutions used in small garden ponds, which are not typical for ponds; moreover, they are expensive and difficult to use and maintain. Therefore, they require the development of a dedicated system that improves the functioning and usability of the filtration system. A modular, compact filtration system for the treatment of water by physical and biological methods, made of polymer composites and with replaceable filtration modules and essential equipment (e.g., skimmers, dispensers, and filtration mats), is a solution expected by many pond users. It enables the exploitation of the natural functions of ponds and contributes to the preservation of biodiversity and active recreation in a biologically living aquatic ecosystem. [ABSTRACT FROM AUTHOR]

Several processes have been developed to treat the textile effluents. Membrane technologies are among the most reliable processes for purifying these effluents. However, due to high costs, only reduced quantities are being treated. The recycling practices of treated textile effluents (TTE) in agriculture have not been appropriately explored. This work evaluates the quality of waters treated by membrane processes and puts forward a scenario for optimizing TTEs in agriculture. Four types of TTE have been tested to irrigate Sesbania bispinosa plants: water from biological treatment (BT) and water from three membrane processes after BT (Ultrafiltration (UF), Nanofiltration (NF), and Reverse Osmosis (RO)). The results indicate that the NF and RO membranes have a high affinity to remove monovalent and multivalent ions. Indeed, the removal of SO42−, Na+, and Cl− by NF was 83, 61, and 55%, respectively. Thus, the RO reduces approximately 96% of these elements. Irrigation with NF and RO waters has no negative effect on the soil and Sesbania plants, contrary to BT and UF waters. It appears that the reuse of TTE resulting from BT is not a good alternative; however, by carrying out additional treatments by NF and RO, their reuses have been made possible. The achieved results are a proposal to simultaneously solve three major problems affecting most of the world's population: (1) environmental pollution by reducing the discharge of untreated textile effluents and improving the quality of this discharged water; (2) the pressure on water resources in the agricultural sector by replacing a conventional resource with a non-conventional resource (TTE); and (3) the lack of fodder, especially in the summer, by opting for crops that adapt to the quality of these TTE. [ABSTRACT FROM AUTHOR]

The paper discusses the current prognoses of aquaculture development worldwide putting an emphasis on its effect on the environment and the issue of the protection of water reservoirs in different countries. Water consumption in diversified aquaculture systems is presented herein as well as the characteristics of the mechanical and biological water treatment methods in fish farms, with particular attention paid to the recirculating water systems. New aquaculture technologies using post-production waters are presented. The paper provides a discussion on the contribution of aquaculture to the global greenhouse gas emissions and the means of limiting this emission. The effect of climate change on aquatic ecosystems is presented in the context of the changes of the aquaculture production profile. The paper includes a brief presentation of the methods of mitigating the changes with respect to contamination of aquatic ecosystems as well as climate change. Reducing the water footprint can be achieved through selective breeding, species diversification and implementation of more technologically advanced aquaculture systems such as: integrated multi-trophic aquaculture, aquaponics and recirculation systems in aquaculture. The need for certification of fish farms with water recirculation systems is justified in the paper. The issues addressed herein are summarised and the main areas for extending the research promoting preservation of aquatic ecosystems in aquaculture are presented. [ABSTRACT FROM AUTHOR]

A continuously stirred tank reactor (CSTR) is largely used in water treatment and in chemical and biological processes. It is characterized by a complex non‐linear behaviour. Operating large reactors in industry can be expensive, so a common trick used to reduce costs is to operate multiple CSTRs in series. Consequently, the CSTR is usually exposed to faults and noises. This paper addresses the design of a robust observer for estimation and fault diagnosis strategy on two CSTRs in series. The considered system is affected simultaneously by time‐varying actuator and sensor faults with measurement noises. The Takagi‐Sugeno multimodel approach is proposed to transform the non‐linear model into an interpolation of several linear sub‐models with non‐measurable premise variables. The purpose of this brief is to provide the state and the fault estimation for the considered system using a proportional multiple integral (PMI) unknown input observer. The exponential stability conditions are studied with the Lyapunov theory and L2 optimization and formulated in terms of linear matrix inequalities. In addition, a comparative study with a PMI observer is conducted. Finally, the proposed observer is used for time‐varying fault detection and isolation. [ABSTRACT FROM AUTHOR]

Water system closure in recycled containerboard mills may have reached a technical limit due to the accumulation of organic and inorganic contaminants in the process water. The specific water chemistry characteristics of recycled containerboard mills with restricted water systems were analyzed and a computer model was developed to simulate calcium carbonate solubility in the presence of volatile fatty acids under relevant mill conditions. A strong linear correlation between VFAs and calcium ions was found. The calcium carbonate dissolution mechanism, solubility, and precipitation were investigated. The reaction of VFAs with calcium carbonate results in the formation of bicarbonate and carbonic acid. By binding hydrogen ions, the carbonate has a pH buffering effect. The carbonic acid dissociates into water and CO2. Gaseous CO2 escapes from the water and leads to decarbonization. This mechanism is responsible for the uncoupling of pH from the concentration of VFAs, as well as from the concentration of dissolved calcium ions. The resulting lack of carbonates prevents the precipitation of calcium carbonate. The introduction of CO2 contained in the biogas produced in anaerobic biological water treatment reverses the dissolution mechanism and causes the precipitation of calcium carbonate. Concentrating technologies such as membrane filtration and evaporation may therefore meet the specific requirements for complete water system closure in recycled containerboard mills better than current commonly used biological treatment. [ABSTRACT FROM AUTHOR]

• 30023 articles and 50326 patents were evaluated by text mining and bibliometric analysis. • Research hotspots of SCI papers were identified by knowledge mapping. • Activated sludge and anaerobic-aerobic combined processes were the mainstream technologies. • Technology evolution path was elucidated in three stages based on the citation network analysis. • Future research and technology innovation directions were proposed. In order to reveal the hotspots and trends of biological water treatment from the perspectives of scientific and technological innovation, both of the bibliometric review and patents analysis were performed in this study. The Web of Science Core Collection database and Derwent Innovation Index database recorded 30023 SCI papers and 50326 patents, respectively were analyzed via information visualization technology. The results showed that China ranked the first in both papers and patents, while the United States and Japan had advantages in papers and patents, respectively. It was concluded through literature metrology analysis that microbial population characteristics, biodegradation mechanism, toxicity analysis, nitrogen and phosphorus removal and biological treatment of micro-polluted wastewater were the research hotspots of SCI papers. Activated sludge process and anaerobic-aerobic combined process were the two mainstream technologies on the basis of patent technology classification analysis. Technology evolution path of biological water treatment was also elucidated in three stages based on the citation network analysis. Furthermore, the future directions including research on the law of interaction and regulation of biological phases and pollutants and the technology innovations towards the targeted biotransformation or selective biodegradation of pollutants and resource reuse of wastewater were prospected. [Display omitted] [ABSTRACT FROM AUTHOR]

In order to improve the removal efficiencies of SS and Fe3+ in anaerobic digestion reject water for the subsequent biological treatment process, on the basis of the single factor test in the early stage, the response surface method was used, and the structure of the formed floc was analyzed by magnetic flocculation. The optimum amounts of magnetic powder, polyaluminum chloride (PAC) and polyacrylamide (PAM) were 40.51 mg/L, 31.31 mg/L and 4.05 mg/L, respectively. At this time, the removal efficiencies of SS and Fe3+ were 97.84% and 98.35%. The effects of floc particle size, scanning electron microscopy, infrared spectroscopy and two-dimensional fractal dimension of flocs on the flocculation ability showed that: compared with conventional coagulation, the average particle size of flocs treated by magnetic flocculation was 76.56 μm, the Fe-O-Al absorption peak appeared at 984 cm−1, the flocculation ability was significantly improved, the surface of the floc was rough and porous, and the structure was dense, and the sedimentation performance was significantly improved also. [ABSTRACT FROM AUTHOR]

Discharging waste water from the bauxite desilication process will bring potential environmental risk from the residual ions and organic compounds, especially hydrolyzed polyacrylamide. Characterization of the microbial community diversity in waste water plays an important role in the biological treatment of waste water. In this study, eight waste water samples from five flotation plants in China were investigated. The microbial community and functional profiles within the waste water were analyzed by a metagenomic sequencing method and associated with geochemical properties. The results revealed that Proteobacteria and Firmicutes were the dominant bacterial phyla. Both phylogenetical and clusters of orthologous groups' analyses indicated that Tepidicella, Paracoccus, Pseudomonas, and Exiguobacterium could be the dominant bacterial genera in the waste water from bauxite desilication process for their abilities to biodegrade complex organic compounds. The results of the microbial community diversity and functional gene compositions analyses provided a beneficial orientation for the biotreatment of waste water, as well as regenerative using of water resources. Besides, this study revealed that waste water from bauxite desilication process was an ideal ecosystem to find novel microorganisms, such as efficient strains for bio-desilication and bio-desulfurization of bauxite. [ABSTRACT FROM AUTHOR]

Nowadays, water defluoridation has become a necessity, for vital human health and for environmental protection through feasible technologies. This present work consists the fluoride absorption study by two algae Chlorella pyrenoidosa and Spirulina, in the exploiting purpose it for industrial water biological treatment. The results obtained allow to know how these algae behave towards toxic substances that can be found in their environment, and so the ability to be used in the water treatment field. However, in the experiment onset, the different environments have fluoride concentration variation from 0.5 to 2.5 mg/L. Just 3 d after; we could notice the almost total fluoride consumption by the cultured cells. Cultivated microalgae cells demonstrated a high fluoride removal with 100% and 84.5% reduction for Chlorella pyrenoidosa and Spirulina respectively. According to the study results, we have shown that the algae are a good bioadsorbent of existing elements in water. In addition, it can be considered that the water treatment by algae is the most modern and suitable technology, because of these advantages its: profitability, ease to use, the quickness for the treatment of all wastewater types. [ABSTRACT FROM AUTHOR]

Koopman-based modeling and model predictive control have been a promising alternative for optimal control of nonlinear processes. Good Koopman modeling performance significantly depends on an appropriate nonlinear mapping from the original state-space to a lifted state space. In this work, we propose an input-augmented Koopman modeling and model predictive control approach. Both the states and the known inputs are lifted using two deep neural networks (DNNs), and a Koopman model with nonlinearity in inputs is trained within the higher-dimensional state space. A Koopman-based model predictive control problem is formulated. To bypass non-convex optimization induced by the nonlinearity in the Koopman model, we further present an iterative implementation algorithm, which approximates the optimal control input via solving a convex optimization problem iteratively. The proposed method is applied to a chemical process and a biological water treatment process via simulations. The efficacy and advantages of the proposed modeling and control approach are demonstrated. • An input-augmented learning-based Koopman modeling approach is proposed. • An iterative MPC is designed to maintain convexity in Koopman MPC problems. • The efficacy of the proposed approach is demonstrated through applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nanocomposite with TiO 2 NPs encapsulated in MWCNTs internal channels for photocatalyst is fabricated. • The fabrication process is facile and is green, solid chemistry without using a solvent. • Selective growth of anatase crystal phase through heating temperature control. • Successful removal of organic dyes and disinfection of biohazardous substances due to photocatalytic effect. Sustainable energy has been widely researched to address issues caused by population growth and rapid industrialization. Among them, photocatalysis using solar energy has been considered promising. We developed a hybrid photocatalyst by combining titanium dioxide (TiO 2) with carbon nanotubes (CNTs), known for their excellent adsorption performance. A unique structure encapsulating TiO 2 nanoparticles (NPs) within the inner space of multi-walled carbon nanotubes (MWCNTs) was developed via a facile, solvent-free method, conforming to green chemistry principles. Except purification and modification of the CNTs, the particle formation process is solvent-free, making this method remarkably simple and environmentally friendly. This arrangement enhances stability and recyclability, maintaining over 90 % efficiency up to the 3rd cycle. X-ray diffraction (XRD) analysis confirmed that the TiO 2 NPs exhibited a crystalline phase, forming exclusively anatase. The defects in the outer walls of the MWCNTs in the composite, coupled with their large specific surface area and dangling bonds, endow them with high adsorption capacity and photocatalytic activity when combined with TiO 2 NPs. The MWCNTs@TiO 2 composites achieved over 99 % inactivation of Escherichia coli in 60 min and bacteriophage MS2 in 30 min, along with dye adsorption/decomposition. This method offers a distinctive platform for photocatalytic degradation in biological applications and water treatment. [ABSTRACT FROM AUTHOR]

Harmful cyanobacterial blooms (HCBs) frequently occur in eutrophic freshwater ecosystems worldwide. Microcystins (MCs) are considered to be the most prominent and toxic metabolites during HCBs. MCs may be harmful to human and animal health through drinking water and recreational water. Biodegradation is eco-friendly, cost-effective and one of the most effective methods to remove MCs. Many novel MC-degrading bacteria and their potential for MCs degradation have been documented. However, it is a challenge to apply the free MC-degrading bacterial cells in natural environments due to the long-term operational instability and difficult recycling. Immobilization is the process of restricting the mobility of bacteria using carriers, which has several advantages as biocatalysts compared to free bacterial cells. Biological water treatment systems with microbial immobilization technology can potentially be utilized to treat MC-polluted wastewater. In this review article, various types of supporting materials and methods for microbial immobilization and the application of bacterial immobilization technology for the treatment of MCs-contaminated water are discussed. This article may further broaden the application of microbial immobilization technology to the bioremediation of MC-polluted environments. [ABSTRACT FROM AUTHOR]

The Rosetta Branch is one of Egypt's most important Nile River branches, providing freshwater to multiple cities. However, its water quality has been deteriorating, with various wastes containing high loads of heavy metals being discharged into its body of water. Seasonally, water and sediment samples and two native aquatic plants (Ceratophyllum demersum and Eichhornia crassipes) were collected and analyzed from the Rosetta Branch to assess the level of metal contamination (Fe, Mn, Zn, Cu, Pb, Ni, Cd, Cr, and Co) using different metal indices. The levels of some metals in the branch water overstepped those suitable for drinking water and aquatic life. In increasing order, the means of the heavy metal concentrations in branch water (µg/L) were Cd (1.8–4.9) < Co (7.18–28.1) ≈ Ni (9.0–25.1) < Cr (8.56–27.4) < Cu (14–75) < Pb (9.3–67.9) < Zn (22–133) < Mn (68–220) < Fe (396–1640). All the metal indices measured in the sediment confirmed the Ni and Cd contamination, where Ni and Cd in the sediment surpass the sediment quality guidelines in 80% and 53% of samples, respectively, reflecting frequent adverse effects on aquatic organisms. According to the bioconcentration factor, C. demersum and E. crassipes have higher accumulation capacities mainly for Cd than those for other metals considered as major pollutants in the water and sediment of Rosetta Branch, reflecting the role of hydrophytes in the biological treatment of polluted water in aquatic environments. [ABSTRACT FROM AUTHOR]

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Ammonia is a common contaminant in municipalities where human waste causes nitrification of local water bodies. In mining, ammonia contamination occurs as a byproduct of biological water treatment, from the use of ammonium nitrate fuel oil in explosives, and from the exposure of ammonia rich soils during the excavation process. In particular, gold mine effluent represents a significant source of ammonia and nitrogen-based contaminants. Current biological and abiotic treatment processes are difficult to employ at the scale required at mine sites due to the high operating costs, or are limited in effectiveness due to a lack of natural resources required to facilitate the treatment. This article evaluates the use of electrooxidation as a cost effective alternative to treating ammonia-laden wastewater in mining applications. Two mixed metal oxide electrodes are assessed in this article: IrO $_{2}$ /Ti and RuO $_{2}$ /Ti anodes. A Monte Carlo simulation is performed to determine a probabilistic range of capital and operating expenditure for a mining operation deploying an electrooxidation wastewater treatment system. The lowest capital cost of operating the electrochemical treatment occurs at a current density of 200 A/m $^{2}$ , where the number of cells required for treatment is minimized. [ABSTRACT FROM AUTHOR]

This work was designed to improve bacterial biodegradation of coomassie brilliant blue and methylene blue dyes by applying carbon nanotubes to facilitate bacterial cell feeding for dyes biodegradation. A bacterial consortium and azobacter were investigated, and conditions for improved biodegradation were optimized. The methodology included; first stage activation of carbon nanotubes by pretreatment with nitric acid for 6 h, washing, and drying at 105°C. The second stage included optimization of biodegradation conditions, using 20 ml glass tubes containing 12 ml of nutrient broth media inoculated with 1 ml of the bacterial source samples. Coomassie brilliant blue or methylene blue (10 mg L−1) was added to the mixture, and the decolorization efficiency was evaluated over time. For the primary adaptation of the biodegradation process, the removal efficiencies for coomassie brilliant blue were 70.2% and 69.2% when using a sand consortium and azobacter, respectively, and for methylene blue they were 81.0% and 82.6% with a sand consortium and azobacter, respectively. The biodegradation process exhibited maximum efficiency at a temperature of 30°C with shaking at 150 rpm. After applying the carbon nanotubes, the removal efficiencies were improved and those for coomassie brilliant blue were 95% and 93% for the sand consortium and azobacter, respectively, and 96% and 99% for methylene blue with the sand consortium and azobacter, respectively. [ABSTRACT FROM AUTHOR]

Methyl tertiary butyl ether (MTBE) is a high soluble oxygenated supplement to fuel that may rapidly contaminate water and soil. Low biodegradability of this compound in the environment has led to more extensive efforts for finding powerful MTBE degrading microbial populations to be used in biological treatment of polluted waters and soils. The present study aimed to isolate MTBE degrading bacteria from petrochemical wastewater and soil of Mahsahar MTBE production site (Iran), and increasing their biodegradation potential in a bacterial consortium. Enrichment of degrading bacteria was done in basal salt media (BSM) containing 50–400 mg/l MTBE. The MTBE degradation pattern was assessed via gas chromatography (GC). The isolates were identified molecularly based on the sequence of 16S rRNA gene. The growth and degradation potential of bacterial consortium was optimized in different pH and temperatures. The best MTBE degrading bacteria were identified as Pseudomonas putida, Pseudomonas aeruginosa, and Enterobacter oryzendophyticus. The first order kinetics for MTBE degradation showed that the bacterial consortium was able to degrade 99.93% of MTBE during 15 days that was 6.08% higher than the most putative monoculture bacterium. The highest MTBE degradation by bacterial consortium was obtained at 30 °C and pH value of 7. The isolated bacterial consortium that involved novel MTBE degrading bacterial strains, decomposed high amounts of MTBE during 15 days of incubation in different temperatures and pH values without addition of co-catalytic substrate is proposed for cost effective removal of this pollutant from the environment. [ABSTRACT FROM AUTHOR]

Background: Wastewaters generated from ubiquitous use of water in daily human activities often contains various pathogenic microorganisms, which may contaminate surface or ground waters when released indiscriminately into the environment. Consumption of natural water resources polluted by such contaminated wastewaters may compromise public health and decrease the populations of aquatic organisms in such water bodies. Mangifera indica (mango) plants have been widely used as remedy for treatment of a wide range of water borne ailments. This study was therefore conducted to identify bacteria contaminating wastewaters from domestic sources and to determine the antibacterial potentials of mango bark and leaf extracts against them. Methodology: Wastewater samples were obtained from the wash areas of five randomly selected female hostels in Bowen University, Iwo, Osun State, Nigeria. Bacteria in the wastewater samples were isolated by standard aerobic cultures and identified using conventional biochemical test schemes. The antimicrobial activities of the methanol extracts of M. indica leaf and bark, and a standard antibiotic (tetracycline), were determined by the modified disc diffusion test. Phytochemical analysis of the extracts was determined by standard method, and the active compounds in them were analyzed by FT-IR spectroscopy using Agilent technologies FT-IR spectrometer at a scan range of 4,000-600 cm-1. Results: The bacterial species isolated from the wastewater samples included Escherichia coli, Proteus mirabilis, Salmonella spp, Pseudomonas aeruginosa and Klebsiella pneumoniae, with E. coli the most frequent (35.7%) and K. pneumoniae the least frequent (7.1%). Leaf extract (30μg) of M. indica exerted high antimicrobial activity against Salmonella spp (inhibition zone diameter of 15mm) while the bark extract exerted high antimicrobial activity against P. aeruginosa (inhibition zone diameter of 13mm). Comparatively, tetracycline (30μg) exerted highest antimicrobial activity against Salmonella spp (inhibition zone diameter of 18mm) but no activity against P. aeruginosa (inhibition zone diameter of 0 mm). The FT-IR analysis confirmed the presence of several functional groups with antimicrobial potentials such as flavonoids, alkaloids, tannins, saponins, phenols, and phytosterols. Conclusion: These results indicate the antibacterial potential effects of M. indica leaf and stem bark extracts against some bacterial isolates, and thus may be recommended for biological treatment of water contaminated by wastewater sources. [ABSTRACT FROM AUTHOR]

The forward osmotic membrane bioreactor (FOMBR) is an emerging innovative technology with broad application prospects in the field of wastewater treatment. Its application is severely limited by concentration polarization, salinity accumulation, and evident water flux decline. Gradual salinity accumulation to a maximum conductivity of 19.7 mS cm−1 under continuous flow operation suppressed the activities of sludge and biodegradation efficiencies. The employment of the regulation of intermittent supernatant discharge was first investigated to alleviate inhibition caused via accumulated salinity in the bioreactor, and bilateral influent was examined with respect to the performance of the FOMBR. The preferable condition to be applied was FO orientation mode (i.e. active layer facing feed) with spacers added to the surface. Given the decreased salt concentration with 2 L of the supernatant removed per day, the water flux declined more slowly and sludge activities were recovered. When compared to the performance without discharging supernatant, the strategy of controlling salinity could improve the removal efficiencies of NH4+-N, PO43--P, and total organic carbon (TOC) by 15.1, 14.3, and 2.3%, respectively. Additionally, the sludge in the intermittent supernatant discharge bioreactor exhibited better sludge property, larger sludge particle size, and recovered sludge activities with the mixed liquid suspended solids (MLSS) stable at around 4.90 g L−1. Therefore, regulation of intermittent salt discharge and controlling the salinity concentration in bioreactor can be employed as an effective method to deal with concentration polarization and salinity accumulation in the FOMBR. [ABSTRACT FROM AUTHOR]

As the CUWCD and EWEB case studies demonstrated, biofiltration provides operators a tool to improve water quality under a range of rapidly changing water quality conditions. Keywords: Utility Management; Biological Filters; Wildfires; Watershed; Water Quality; Water Treatment EN Utility Management Biological Filters Wildfires Watershed Water Quality Water Treatment 76 79 4 06/05/21 20210601 NES 210601 GLO:KNS/01jun21:awwa1729-gra-0001.jpg PHOTO (COLOR): . gl I The Hayden Bridge Filtration Plant in Eugene, Ore., is one of many facilities to implement biofiltration as part of a robust, sustainable drinking water treatment system. [Extracted from the article]

Bioaerosols are emitted during the biological treatment of water, soil, and air pollutants. The elimination of these pollutants has become a priority due to their detrimental effects on human health. Advanced oxidation technologies have been used to control bioaerosol emissions specially to improve indoor air quality. This investigation was focused on evaluating the biofiltration of ethyl acetate vapors in terms of removal efficiency and bioaerosol emission. Also, a continuous photocatalytic process to inactivate bioaerosols emitted from the biofilter was assessed as a post-treatment. The photocatalysis was developed with ZnO and TiO2 immobilized onto Poraver glass beads. Flow cytometry (FC) coupled with fluorochromes was used to characterize and quantify bioaerosol emissions in terms of live, dead, and injured cells. Ethyl acetate removal efficiencies were maintained in a steady state with values of 100% under 60-g m−3 h−1 inlet load (IL). Biomass concentration in the biofilter reached values up to 228 mgbiomass gperlite−1 at day 56 of operation, but the spontaneous occurrence of predatory mites diminished biomass concentration by 33%. Bioaerosols emitted during the steady-state operation of the biofilter were composed mainly by bacteria (~ 94%) and in a less extent of fungal spores (0.29–6%). The most efficient photocatalytic system comprised TiO2/Poraver with 78% inactivation of bioaerosols during the first 2 h of the process, whereas the ZnO/Poraver system showed null activity (~ 0%) of inactivation. FC results show that the main mechanism of inactivation of TiO2/Poraver was cell death. [ABSTRACT FROM AUTHOR]

In wastewater treatment plants (WWTP), it is common to bypass non-compliant effluents based either on a visual estimate or on variations of the global parameters, in order to preserve the water biological treatment. This is often adopted when these parameters increase or an apparent change in the color of the influencers feeding the treatment plant. However, the dilution of wastewater by the clear waters attracts no attention and no alarm management position. Consequently, the main purpose of this study is to draw the attention of the WWTP managers to this fact often classified as not dangerous and not alarming, the effects of feeding disturbances and nutritional deficiencies caused by the presence of clear waters considered as parasites, will be evaluated on the treatment efficiency, the microbial activity, the flocculation status, and the microbial morphology, using a semi-continuous reactor, fed by a synthetic substrate obtained after leaching of 5 g L–1 animal feed for 4 h. The nutrient deficiency caused by the introduction of clear water into the sanitation networks causes not only the excessive proliferation of filaments by reaching a filamentous index (FI) of 5, but also the opening of microbial floc. Decantation was completely reduced and a decrease in the maximum exogenous respiration of 92.55% was recorded when the nutrients in the synthetic substrate were reduced by a factor of 1/10. [ABSTRACT FROM AUTHOR]

In recent years, microbiological treatment to remediate contamination by heavy metals has aroused public attention as such pollution has seriously threatens ecosystems and human health and impedes sustainable development. However, the aspect of actual industrial wastewater and solid waste remediation by microorganisms is not explored sufficiently. And what we focus on is technical field of microbial remediation. Therefore, in this review, we discuss and summarize heavy metal treatment via microbiological approaches in different media, including wastewater, solid waste from industrial factories and polluted sites. We also clarify the technical applicability from the perspective of biosorption, bioleaching, biominerization, etc. In particular, the exploration of the combination of microbiological approaches with chemical methods or phytoextraction are scrutinized in this review relative to real waste heavy metal remediation. Furthermore, we highlight the importance of hyperaccumulator endophytes. [ABSTRACT FROM AUTHOR]

Pakistan is facing the most horrible disasters of water scarcity since two decades. Due to which wastewater is directly used for agriculture without secondary and tertiary treatments which is affecting the soil, plant and human health negatively. In this study wetland technology was used for the biological treatments of waste water using aquatic plants for irrigation. In a prototype experiment, different effluents were treated and their optimal hydraulic retention time (HRT) was found. A comparison was made between predicted and observed values after using a modeling approach. RCBD experimental design with three treatments was selected for the study, where each treatment had three replications. Water lettuce (Pistiastratiotes L.), pennywort (Centella asiatica L.) and duckweed (Lemnoidea elemna Minor L.) aquatic plants were used for wastewater treatment. The wastewater quality was analyzed before and after treatment for particular parameters such asEC, Ca, Mg, Na and heavy metals including Fe and Cu. Sodium Adsorption Ratio (SAR) was also calculated on the basis of results of Ca, Mg and Na. Results showed the range of reduction efficiency of EC, Ca, Mg, Na and heavy metals 3-26%, 6-36%, 0-92%, 12-75% and 4-35%, respectively. On the basis of this study, development of decision support system (DSS) was made to design a constructed wetland (CW) which is most efficient for the treatment of various types of wastewater. Policy guidelines were established for the safe reuse of treated wastewater for irrigation purpose. [ABSTRACT FROM AUTHOR]

A hybrid fluidized‐bed bioreactor for water purification was proposed and analyzed. It is a novel type of bioreactor characterized by hitherto unknown stationary and dynamic features. Steady‐state characteristics of this hybrid bioreactor with external liquid circulation are presented. A quantitative analysis of steady‐state properties of the bioreactor was performed with the aid of an original mathematical model developed for a double‐substrate aerobic microbiological process. A steady‐state analysis of aerobic processes characterized by different oxygen demand was performed. The effect of essential parameters was evaluated, including carbonaceous substrate concentration in the feed stream to the apparatus, aeration intensity, total residence time of a liquid in the bioreactor, and height of the bed of fine carrier particles. [ABSTRACT FROM AUTHOR]

A modified rotating packed disc contactor (RPDC) with the maximum working volume of 65 liter is designed for biological waste water treatment. A hollow disc with radial vanes mounted on the disc was a modified design of this contactor. Stimulus-response experiments were conducted in the contactor to understand liquid mixing behavior under different operating conditions. The recycle stream was also used in the operation of the contactor. Experiments were conducted for different number of discs, rotational speeds and recycle ratios. The disc design and recycle ratio had marked influence on the mixing behavior. An increase in disc rotation and recycle ratio produced a well-mixed flow behavior. Moreover, the surface area available in the RPDC was about 4 times more than the surface area available in a standard rotating biological contactor (RBC) operating at similar conditions. A mathematical model was developed for the flow behavior under recycle and a good agreement was found between the model and experimental results. [ABSTRACT FROM AUTHOR]

Global water demand is continuously growing due to rising population and associated industrial and agricultural activities. However, these factors are also polluting the existing water bodies and therefore, limiting the water supply. Increasing level of contaminants poses risk to human, wildlife and the environment. Widening gap between water demand and supply creates water stress. Therefore, treatment of waste water becomes imperative in order to ensure sustainable development of planet earth. Conventional methods utilizing physical, chemical and biological processes are generally adopted for this purpose. These methods are further modified so as to enhance the efficiency and economy of the treatment process as well as to make them more eco-friendly. None of the conventional or advance technology is individually sufficient for appropriate treatment of wastewater. Therefore, more efficient hybrid methods are required. The development of such hybrid methods needs detailed information about various treatment methods. This paper critically reviews the conventional and advanced biological methods used for waste water treatment. The main objective of this review is to present vital information about various biological treatment methods forming the basis for the development of sustainable hybrid methods for waste water treatment. [Display omitted] • Increase of contaminant level is causing severe water pollution globally. • This is a major bottleneck in the way of SDG-6. • Conventional wastewater treatment techniques are not sufficient. • Hybrid/advanced biological techniques have higher treatment efficiencies. • This review focuses on advanced biological wastewater treatment techniques. [ABSTRACT FROM AUTHOR]

Bacteria are primarily responsible for biological water treatment processes in constructed wetland systems. Gravel in constructed wetlands serves as an essential substrate onto which complex bacterial biofilms may successfully grow and evolve. To fully understand the bacterial community in these systems it is crucial to properly isolate biofilms and process DNA from such substrates. This study looked at how best to isolate bacterial biofilms from gravel substrates in terms of bacterial richness. It considered factors including the duration of agitation during extraction, extraction temperature, and enzyme usage. Further, the 16S taxonomy data subsequently produced from Illumina MiSeq reads (using the SILVA 132 ribosomal RNA (rRNA) database on the DADA2 pipeline) were compared with the 16S data produced from Oxford Nanopore Technologies (ONT) MinION reads (using the NCBI 16S database on the EPI2ME pipeline). Finally, performance was tested by comparing the taxonomy data generated from the Illumina MiSeq and ONT MinION reads using the same (SILVA 132) database. We found no significant differences in the effective number of species observed when using different bacterial biofilm detachment techniques. However, enzyme treatment enhanced the total concentration of DNA. In terms of wetland community profiles, relative abundance differences within each sample type were clearer at the genus level. For genus-level taxonomic classification, MinION sequencing with the EPI2ME pipeline (NCBI database) produced bacterial abundance information that was poorly correlated with that from the Illumina MiSeq and DADA2 pipelines (SILVA132 database). When using the same database for each sequencing technology (SILVA132), the correlation between relative abundances at genus-level improved from negligible to moderate. This study provides detailed information of value to researchers working on constructed wetlands regarding efficient biofilm detachment techniques for DNA isolation and 16 s metabarcoding platforms for sequencing and data analysis. • Different detachment techniques did not change the effective number of species. • Enzyme treatment enhanced the total concentration of DNA. • Wetland samples showed differences in the genus-level bacterial relative abundance. • Genus-level correlation was poor between MiSeq and MinION using different databases. • Genus-level correlation was moderate between MiSeq and MinION using the same database. [ABSTRACT FROM AUTHOR]

Biofouling is an important biological constrain in the water treatment process, and the control or management strategies using green principles have gained recent attention. Antibiofouling agents based on the biological source are now extensively studied due to their high efficacy and are environmentally friendly. In this present study, Poly Acrylo Nitrile (PAN)/Ulvan hollow fibre membranes of four different modules were fabricated for water treatment studies by testing against B. subtilis and E. coli along with separation efficiency studies on proteins such as albumin, pepsin, and clay. Ulvan (Ulv), green seaweed sulfated polysaccharide extracted from Ulva fasciata, was coated on PAN hollow fibres, fabricated using a wet-spinning process. Ulvan was dip-coated on membrane surface followed by cross-linking and resultant changes in terms of performance and morphology. PAN/Ulv hollow fibre membranes were examined for the pure water flux and protein separation analysis to analyse the membrane efficiency. SEM was used to analyse the membrane structure and ATR- FTIR for the determination of functional groups. Ulvan coated (310 C) hollow fibre membrane showed better performance than the other three membranes with a flux of 398.1 L m−2 h−1. Higher sample concentration of suspended solids paved simpler route for enhanced COD sequestration efficacy. Pepsin, albumin, and clay particles were rejected by the 310C Ulvan adorned membranes at rates greater than 80%. By incrementing suspended particles beyond 3200 mg/L, the greatest power recovery was reduced that portrays an adverse influence of bio-fouling process on membrane operation. Experimental results demonstrated that synthesised 310 C membrane possessed better separation performance and antifouling characteristics for aquatic water systems. [Display omitted] • Ulvan is a coating material for PAN hollow fibre membrane. • 310 C fibre showed good performance in terms of pure water/energy flux and protein rejection. • Thermodynamic interactions among H2O/Ulvan/PAN membrane has been carried out. • Notable anti-biofouling impact is observed on the bacterial biofilm architecture in the Ulvan coated fibre membrane. [ABSTRACT FROM AUTHOR]

The presence of objectionable taste-and-odor (T&O) compounds in surface water supplies is a common problem facing drinking water utilities across the country and worldwide. While there are several viable T&O treatment options, including adsorption, biotransformation, and advanced oxidation, no single option fits all applications or is without potential limitations. Through bench- and pilot-scale testing, this work developed and evaluated high-rate biological roughing filtration as a promising alternative for geosmin and 2-methylisoborneol abatement to help utilities minimize T&O complaints without straining their annual operating budgets. Testing showed that biological roughing filtration can effectively treat a wide range of raw water T&O levels using short contact times, and the intermittent presence of T&O compounds did not appear to appreciably affect removal efficacy. Pilot-testing results were used to develop the design criteria for a full-scale 54-mgd biological roughing filter that is currently treating surface water in Manatee County, Florida. [ABSTRACT FROM AUTHOR]

Traditional biological contact oxidation (BCO) process was modified; influent, stirring, aeration, sedimentation, and effluent were carried out alternately in the same BCO reactor to realize anaerobic reaction, anoxic reaction, and aerobic reaction. Micro-polluted water with low carbon-to-nitrogen (C/N) ratio was treated by the modified BCO process. Effects of aeration mode, hydraulic retention time (HRT), and ratio of air to water (A/W) on the removal of CODCr (chemical oxygen demand), NH4+-N, total nitrogen (TN), and total phosphorus (TP) were investigated, and the analysis of microbial community structure was also conducted. Results showed that when the A/W ratio was 6:1 and the HRT was 9 h, better removal effect was achieved for the operation mode of intermittent influent and intermittent aeration; the removal efficiencies of CODCr, NH4+-N, TN, and TP were 72.45%, 94.50%, 83.38%, and 74.23%, respectively. While for the operation mode of continuous influent and continuous aeration, when the HRT was 9 h and the A/W ratio was 6:1, removal efficiencies of CODCr, NH4+-N, TN, and TP were 71.90%, 99.10%, 28.48%, and 45.45%, respectively. Results of microbial community analysis showed that Ignavibacterium, Pirellula, Gemmata, and Candidatus Hydrogenedens with anaerobic ammonia oxidation (Anammox) function existed in the dominant populations; the relative abundances of the four bacteria in the intermittent aeration reactors were higher than those in the continuous aeration reactors. Relative abundances of Defluviimonas, Hyphomicrobium, and Longilinea with denitrification function were also higher in the intermittent aeration reactors. Results of microbial population analysis also showed that higher nitrogen removal efficiencies were observed for the intermittent aeration reactors. The modified BCO process was suitable for the treatment of micro-polluted water with low C/N ratio characteristics. [ABSTRACT FROM AUTHOR]

A high-voltage device for generating low-temperature plasma in water that is saturated with air bubbles is considered. It contains a discharge chamber and a generator of voltage pulses with an amplitude of ~30 kV and a rise time of ~5 μs, which is able to form spark discharges with an energy of ~1 J at a frequency of several hundred hertz. The electric circuit of the generator of discharges in water, which provides its high efficiency, and the design of the discharge chamber, which allows formation of parallel air flows through the water-filled interelectrode gap, are described. The results of studies of electric-discharge processes and the results of the chemical analysis of water samples that are enriched with products of plasmochemical reactions are presented. The possibility of the accelerated development of plants that are irrigated with plasma-treated water is shown. [ABSTRACT FROM AUTHOR]

Sanitary landfill leachate had been described as the most polluted wastewater. The available technologies to treat leachate landfills are physical/chemical and biological treatment. However, literature shows that filtration technique is preferable, as the selective materials are easily obtained and required minimum cost. The aim of this study is to treat pollutants (BOD, COD, ammoniacal nitrogen, zinc, and copper) in leachate using peat moss as sole adsorbent and co-adsorbent with bentonite. The research was conducted by measuring initial and final concentration of pollutants in leachate. Based on the results, the percentage removal of the BOD, COD, ammoniacal nitrogen, zinc, and copper using peat as single adsorbent 26.2%, 91.97%, 83.4%, 96%, and 90%. While using mixed adsorbents are 31.3%, 94.6%, 89.1%, 90.6%, and 90%. The total volume of leachate was 1200 mL able to pass through sole adsorbent of peat moss within 14 h. In conclusion, leachate can be treated efficiently using peat moss with the addition of bentonite. [ABSTRACT FROM AUTHOR]

• Nine genes from different microorganisms were synthesized and modified. • Phenol was degraded completely and imported into the tricarboxylic acid cycle. • All genes were regulated by monocistronic transcriptional pattern. • The engineered E. coli could effectively degrade phenol in coking wastewater. Phenol is a common water pollutant because of its broad industrial applications. Biological method is a promising alternative to conventional physical and chemical methods for removing this toxic pollutant from the environment. In this study, two metabolic modules were introduced into Escherichia coli, the widely used host for various genetic manipulations, to elucidate the metabolic capacity of E. coli for phenol degradation. The first module catalysed the conversion of phenol to catechol, whereas the second module cleaved catechol into the three carboxylic acid circulating intermediates by the ortho- cleavage pathway. Phenol was completely degraded and imported into the tricarboxylic acid cycle by the engineered bacteria. Proteomics analysis showed that all genes in the phenol degradation pathway were over-expressed and affected cell division and energy metabolism of the host cells. Phenol in coking wastewater was degraded powerfully by BL- phe/cat. The engineered E. coli can improve the removal rate and shorten the processing time for phenol removal and has considerable potential in the treatment of toxic and harmful pollutants. [ABSTRACT FROM AUTHOR]