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In this work, a rapid and simplified method for extracting SARS-CoV-2 RNA from whole wastewater using a magnetic beads-based protocol is presented. The described method involves the centrifugation of a 50-mL aliquot of raw wastewater influent for 5 min to obtain a 500-μL pellet, which is eluted with 2 mL of a Tween®20-based elution buffer; 1 mL of the elute is extracted for RNA using a direct magnetic bead-based extraction method. RNA recovery was examined in several bench-scale experiments using heat-inactivated SARS-CoV-2 (HI-SCV-2) spiked into raw wastewater to assess the effects of different solids pellet : buffer ratios, inhibition mitigation strategies, and varying levels of total suspended solids. When the method was assessed using an influent wastewater sample known to contain SARS-CoV-2, the viral signal was detected in all five biological replicates, whereas direct extraction of 1-mL aliquots of the raw wastewater resulted in a 40% viral detection rate. The experimental method limit of detection (MLOD) using HI-SCV-2 spiked into raw wastewater was 50 GU mL−1 with a 95% limit of detection. Using the described protocol, the presence of SARS-CoV-2 RNA was verified in wastewater collected from wastewater treatment facilities (WWTFs) in Atlantic Canada over a period of 15 weeks during the rise and fall of a COVID-19 outbreak. This method is effective and rapid and could provide potential application for laboratories with limited resources. Of approximately 50 methods that have been developed for measuring SARS-CoV-2 in wastewater referenced in the literature, this is the first to advance a robust magnetic beads-based RNA extraction technique from whole wastewater without extensive sample pre-treatment. The novel application of this method in the rapid extraction of SARS-CoV-2 RNA from municipal wastewater is an indispensable tool to potentially understand COVID-19 infection occurrence within communities.

Pollutants discharged by roads may impact water bodies and soils. The best method to characterise road runoff is by monitoring, which is not always possible due to human or material constraints. Therefore, prediction tools can be a valuable method to manage road runoff discharges and protect the environment. The present work reviewed and evaluated international tools for road runoff quality prediction, in order to assess if an existing tool could be suitable for wide usage by stakeholders in Europe. Four tools from the USA and Europe were selected and tested at 22 road sites located in regions with annual precipitation values ranging from 500 to 1,000 mm, from seven European countries. The results for the site median concentration (SMC) of total suspended solids (TSS), Zn, Cu, Pb and Cd showed coefficients of determination (R2) from 0.0004 to 0.2890 for the different pollutants and tools. It was concluded that none of the tools could predict the road runoff pollutant concentrations, except for the country where it had been calibrated. The findings support practitioners and researchers all over the world, pointing out directions, and gaps to be filled, regarding the management of road runoff discharges and use of prediction tools. HIGHLIGHTS Tools for road runoff quality prediction could support environmental management.; Evaluation of tools in seven European countries with monitoring data sets.; Site median concentrations of road runoff change over time and region.; It is not feasible that a tool accounts for the whole phenomena of road runoff.; Need for innovative approaches in water management under climate change.

Stormwater runoff contains a myriad of pollutants, including faecal microbes, and can pose a threat to urban water supplies, impacting both economic development and public health. Therefore, it is a necessity to implement a real-time hazard detection system that can collect a substantial amount of data, assisting water authorities to develop preventive strategies to ensure the control of hazards entering drinking water sources. An on-line UV-Vis spectrophotometer was applied in the field to collect real-time continuous data for various water quality parameters (nitrate, DOC, turbidity and total suspended solids) during three storm events in Mannum, Adelaide, Australia. This study demonstrated that the trends for on-line and comparative laboratory-analysed samples were complimentary through the events. Nitrate and DOC showed a negative correlation with water level, while turbidity and total suspended solids indicated a positive correlation with water level during the high rainfall intensity. The correlations among nitrate, DOC, turbidity, total suspended solids and water level are the opposite during low rainfall intensity. Nitrate, one of the main pollutants in stormwater, was investigated and used as a surrogate parameter for microbial detection. However, the microbiological data (Escherichia coli) from captured storm events showed poor correlations to nitrate and other typical on-line parameters in this study. This is possibly explained by the nature of the stormwater catchment outside of rain events, where the sources of bacteria and nutrients may be physically separated until mixed during surface runoff as a result of rainfall. In addition, the poor correlations among the microbiological data and on-line parameters could be due to the different sources of bacteria and nutrients that were transported to the stormwater drain where sampling and measurement were conducted Refereed/Peer-reviewed

Wanggu River is the largest river in Kendari City – Southeast Sulawesi (Sultra), whose condition is very poor because it is a final place for disposal of household and industrial wastewater. It will be impacted by decreasing water quality and silting sedimentation. In this study, it is important to analyze the water quality of the Wanggu River with several physical and chemical parameters analysis such as the determination of total suspended solids (TSS), biochemical oxygen demand (BOD), the content of phosphate (PO4), and detergent pollutants which are determined based on location sampling such as upstream, middle, and downstream. Based on these results showed that the TSS and PO4 contents from the upstream, middle, and downstream points had increased in concentration, while the BOD and detergent contents have decreased in the downstream area. However, this condition shows that the Wanggu River is still categorized as Class II within the normal threshold. These results are expected to become a reference for the government and society in improving wastewater management and increasing knowledge in managing river water quality.

The use of low-cost on-site wastewater treatment technologies, including constructed wetlands (CWs), is wide spread. Despite the purported high performance of vertical-horizontal subsurface flow (V-H SSF) hybrid CWs, data on implementation and performance in developing countries is scarce. Here, the design, operation and performance of V-H SSF hybrid CWs for treatment of municipal sewage in an effort to encourage and direct future research and assist technology choice were reviewed. Literature reveals that successful performance of V-H SSF hybrid CWs depends mainly on system design and is independent of mode of feeding. Moreover, performance and final effluent quality is high for biological oxygen demand (BOD), chemical oxygen demand (COD) and total suspended solids (TSS) which are all reduced by over 80%. Despite high removal of ammonium-nitrogen (NH4+-N), concentration in the final effluent remains above desired levels, which is attributed to the design of V-H SSF hybrid CWs based on BOD as a parameter of choice, rather than nitrogen. It was argued that further research on performance of V-H SSF hybrid CWs based on designs that consider both nitrogen in the form of NH4+-N and BOD and assessment under different climatic conditions, is essential prior to mass implementation of this technology in developing countries. Key words: Hybrid constructed wetlands, municipal wastewater, pollutant removal.

The purpose of this study is to evaluate the impact of several pre-selected carrier materials used in an Inverse Fluidized Bed Reactor (IFBR) on the treatment efficiency of distillery spent wash water. Distillery spent wash water has been identified as a threat to the natural environment due to its high pollution load. The effluents from the industry are dark brown in color and contain heavy organic matter, causing a high Biochemical Oxygen Demand (BOD5) and Chemical Oxygen Demand (COD); however, they can be treated effectively through biological processes. Previous research reveals that a high-rate anaerobic digester especially an IFBR reduces COD more effectively than other treatment technologies. The effectiveness of the reactor depends on the expansion of the fluidized bed which in turn is related to the carrier material. In this study, four different carrier materials: perlite, expanded perlite, sawdust and polystyrene, were selected. The carrier materials selected were assessed based on their efficiency in reducing COD, Total Solids (TS), Total Dissolved Solids (TDS) and Total Suspended Solids (TSS). Results were taken at 140-h Hydraulic Retention Time (HRT), with a constant Organic Loading Rate (OLR) of 12 kg COD/m3/day. Among the selected carrier materials, expanded perlite was most effective at reducing COD, TS, TDS and TSS (83.33, 72.47, 29.67 and 88.78%, respectively). This method could be easily implemented in industrial practice and thereby reduce the negative impact of production plants on the natural environment.

Intermittent planted filters are extensive biological purification techniques aimed at oxidizing and decontaminating urban wastewater at a low cost and with minimum environmental impacts. The main purpose of this study was to evaluate the performances of intermittent planted filters in treating urban wastewater under arid conditions of southern Tunisia. The experimental study was carried out on a pilot scale plant comprising five constructed gravel-sand basins. Screened urban wastewater effluent was intermittently applied with a daily hydraulic load of 400 L/m2. Several water quality parameters were monitored at the inlet and outlet of this treatment plant. The average removal rate were 94.8%, 92.3%, 99.3%, 89.9% and 93.3% for chemical and biological oxygen demand, total suspended solids, ammonium nitrogen and orthophosphate, respectively. Additionally, results demonstrated that this treatment system is capable of removing 3.67, 3.22 and 2.44 log units of total and faecal coliforms, and faecal streptococci, respectively. Results showed that Phragmites australis allowed the development of biofilm in the sand filter beds, improving their purification efficiency. Furthermore, no bio-sludge production, no mechanical aeration, low energy requirement (0.02 kW/m2) and green aesthetic ambience are the additional particular strengths of the proposed pilot plant. HIGHLIGHTS Planted filters are efficient in treating urban wastewater under arid conditions.; Results showed that Phragmites australis improved the purification efficiency of the planted filters.; Planted filters accomplished significant removal rates of organic and nitrogen matter.; This treatment system led a significant abatement of pathogens.; The treated wastewater can be reused in irrigation.

Refinery effluents represent an emission source of hydrocarbons (HCs) and other constituents to the environment. Thus, characterisation of effluent quality in terms of concentrations of key parameters relative to permitted standards is important and for total petroleum hydrocarbons (TPH), the specific composition of the HC mixture can affect its toxicity to aquatic organisms. Therefore, this study was designed to analyse TPH, benzene, toluene, ethyl benzene, xylenes (BTEX), polycyclic aromatic hydrocarbons (PAHs), (bio) chemical oxygen demand, total nitrogen, total suspended solids and selected metals before, and after, treatment steps to demonstrate removal efficiencies across 13 refineries with variable wastewater treatment systems. Final discharge concentrations of the measured parameters were by 97% within the so called Best Available Technique Associated Emission Levels (BAT-AELs). Further, TPH composition was characterised using high-resolution two-dimensional gas chromatography (GCxGC) analysis to understand the mass distribution by carbon number and specific chemical class. Measurements were compared to SimpleTreat model predictions for validation. SimpleTreat successfully predicted the shape of the effluent composition since it is essentially a removal constant applied to the influent composition. The predictions were of similar magnitude as, or were greater than, the effluent concentrations since SimpleTreat is based on typical performance and is intended to be conservative. This was especially true for aromatic constituents. Reduction in potential HC exposures also coincided with a decrease in predicted toxicity using a mechanistic oil toxicity model, PETROTOX. Overall, the results indicate that EU petroleum refineries are likely to achieve a high performance level regarding effluent treatment.

Water and soil qualities play significant roles in the farming of giant freshwater prawn. The study evaluated water and soil qualities for giant freshwater prawn farming site suitability by using Analytic Hierarchy Process (AHP) and Geographic Information System (GIS) in Jelebu, Malaysia. The water quality parameters measured were biochemical oxygen demand, chemical oxygen demand, ammonia nitrogen, pH, dissolved oxygen, water temperature, total suspended solids, nitrite concentration and phosphate concentration, meanwhile soil qualities investigated were land use, slope, pH, texture, organic carbon and organic matter. Site suitability analysis can assist to identify the best location for prawn production. Specialist's opinions were used to rank the level of preference and significance of each of the parameter while the pairwise comparison matrix was applied to calculate the weight of each parameter for prawn farming. There are about 45.41% of the land was most suitable, 28.89% was moderately suitable while 25.69% was found unsuitable for prawn farming. The combination of AHP and GIS could give a better database and guide map for planners and decision-makers to take more rewarding decisions when apportioning the land for prawn farming, for better productivity.

Globally an enormous amount of sewage and sludge is being generated which has turned out to be a major environmental threat due to the associated risks arising from heavy metals. In this context the present study aimed to assess the concentration of heavy metals in sewage and sludge from wastewater treatment plants located around Dal Lake of Srinagar city. Aluminum, iron, zinc, lead, copper, mercury, arsenic, cadmium and chromium were determined using atomic absorption spectrophotometer. Certain key physico-chemical characteristics of sewage in raw and effluent were also evaluated. Health risk assessment using non-carcinogenic and carcinogenic risk revealed suitability of sludge in agriculture which till now remain a neglected resource in the city. Principal component analysis showed that the maximum variability in the data was reflected from sludge samples, whereas correlation among physico-chemical parameters and heavy metals revealed influence of ionic properties of wastewater on heavy metal distribution. While concentration of heavy metals was within the discharge standards, physico-chemical parameters like total suspended solids, ammonia, biochemical oxygen demand and total phosphorus were exceeding the standards meant for effluent disposal. This is one of the unique situations wherein the waste water from the entire city is discharged into Dal Lake without subjecting to advanced treatment. Since the lake is directly linked with supply chain of food and water, continuous discharge of heavy metals have the potential to build up toxicity and cause harm to the lake biota and public health thereof.

Water treatment for human uses is a vital asset to economic development. This article focuses on a combination of physical, biological, and chemical processes. Methods of water treatment require concrete or steel base structures, rendering them heavy, costly, and time-consuming to establish. Water treatment systems should be economically viable and practicable in design for developing societies; hence, structural builds should be simplified. Novel structures, a series of polyethylene cyclonic ponds for water treatment, were built and tested. Tanks were equipped with a settled material central outlet, water side outlet, and a pump shower system that enabled sludge removal without mechanical intervention. A freely flowing vortex was produced, aerated, given a biological treatment, and finally mixed with a chemical treatment step. Test establishment of the batch system enabled improvement in water quality, with removal performance as follows: TSS (total suspended solids) = 98%, UV254 absorbance = 50%, DOC (dissolved organic carbon) = 56%, and turbidity=95%. The batch system builds of the current study required short construction time and were economically priced. Cyclonic ponds are suited to diverse usage. The value may be felt in the improvement of water quality for human consumption, utility, and ecosystem services to counter the extensive pollution caused by oil and gas extraction and other industries.

Objectives: To evaluate the importance of solar-based Electrocoagulation followed by the filtration process in treating the domestic greywater, analyze each operational process’s performance process in highlighting the cost, efficiency and reuse conditions. Analysis: This research aimed to see if the continuous mode EC technique could treat Greywater (GW) with batterypowered solar energy. The EC process running on solar energy is used as a single unit method for Greywater treatment. This explores the hybrid electrocoagulation and filtration process with different electrode material combinations with a flow rate; based on this, and the impact tests are carried out on the flexibility of continuous mode, anode and cathode efficiency. Findings: In this experiment, using a combination of electrodes with different material having continuous flow find about removal efficiencies of different characteristics like COD, Total dissolved solids, Total suspended solids, pH and Turbidity with the variable in the supply of current with fix detention time. Novelty:Experimental approach based on Solar based Electrocoagulation with filtration mechanism is the new concept of approach for treating Domestic Greywater Keywords: Domestic Greywater; Solar energy; Electrocoagulation; Continuous mode; Controlled flowrate; Filtration

The study examines the groundwater quality of Kaduna south Local government area. The physio-chemical analysis of PH, sulphate, Phosphate, chloride, Iron, Electrical conductivity, Turbidity, Nitrates, Total suspended solid and Total hardness were carried out, the result obtained were compared with World Health Organization (WHO) recommended standards for drinking water. pH, sulphate, electrical conductivity, chloride, nitrate, total suspended solids, and total hardness in all location were within the acceptable standards of WHO. The collected data from the laboratory analysis were analyzed using simple tables, graphs and charts and the result reveals that turbidity and iron in all location were above the acceptable standards of WHO. Turbidity which is above the WHO with a significant value at all the eight sampling points with 25.3,22.6,28.7,11.6,9.05,9.05,10.4,14.3 NTU respectively, Iron concentration in all the sampling points is high with 35.0, 30.0,26.0 15.0,12.0,10.0, 15.0,11.0 mg/l respectively. Large amounts of Iron in drinking water can give it an unpleasant metallic taste. Iron is an essential element in human nutrition, and the health effects of iron in drinking water may include warding off, fatigue and anaemia (metaglobinaemia).Groundwater exploitation especially boreholes should be regulated by government in order to reduce the negative effect of water pollution to humans. This research reveals there is great need to analyze any ground water before drinking

This paper presents results of the research carried out on a system made to pretreat the effluents produced in water treatment of dirty surfaces of railway transportation means (RTMs) mainly G, H, T and incidental F classes of rolling stock according to the International Union of Railways (IURs). The installation was designed for coagulation–flocculation pretreatment of wastewater with flow accelator reactor (AR) in total amount of up to 75.0 m3 day−1. The raw wastewater (RW) was characterized by a significant diversity of loads: TSS (total suspended solids), TDS (total dissolved solids), COD & BOD5 (chemical & biochemical oxygen demand) and periodically it had extremely different colors, Ta (turbidity) and EE (etheric extract). The application of two-stage, coupled acid-alkali or alkaline-acid coagulation using aluminum coagulants with final flocculation and phase separation in the system implemented in practice to treat the wastewater of statistically typical composition, usually allowed to removal, accordingly: EE & TSS > 99% and to eliminate completely color and Ta. However, COD and BOD5 were removal at different levels, depending on both initial concentrations and chemical composition of load pools registered in the RW, and a type of coagulation used. The use of pre-oxidation with aqueous solutions of hydrogen peroxide or peracetic acid coupled with coagulation based only on aluminum coagulants helps to achieve equal levels of removal of the basic indicator values and a sanitary clean stream of pretreated wastewater (PW) with a colony forming unit (CFU) of −1.

A novel photocatalytic continuous system has been proposed for the treatment of tannery waste water, which has high levels of environmental pollutants. The purification process was performed by passing wastewater on a titanium dioxide (TiO2)-coated surface, which is continuously activated by irradiation of ultraviolet light. To improve the yield of the process, ferric chloride (FeCl3) was used as a coagulation agent. The organic and inorganic compounds, as well as the microorganisms in the tannery wastewater media, were degraded through a photocatalytic process. The results revealed that total dissolved solids and total suspended solids contents were significantly decreased from 8,450 and 8,990 mg·L−1 to 4,032 and 4,127 mg·L−1, respectively. Furthermore, the chemical oxygen demand content of the sample was reduced from 370 to 50 mg·L−1 after the addition of 100 mL of FeCl3 and 4 h of treatment. The same results were observed for the elimination of sulfate and chromium ions, which led to a decline in electrical conductivity. This suggests that introducing 100 mL of FeCl3 as the coagulation agent and continuous treatment with photocatalityc set-up could be considered as an effective method for the purification of tannery wastewaters. HIGHLIGHTS Continuous set-up fabricated for tannery wastewater treatment using photocatalytic reactions.; TiO2 photocatalyst activated by UV light for improvement of purification yield.; FeCl3, as coagulation agent, facilitated treatment by removing total dissolved solids.; Toxic ions and microorganisms were eliminated in this method.

This study investigates the impact of wastewater irrigation on soil–plant–water system at the vegetative, flowering, and reproductive stages of Phragmites australis for two and four days (in each stage) in the coastal saline area of Urmia Lake. The concentrations of potentially toxic elements were detected in irrigated water, soil, and plant (aboveground and belowground) tissues, and transfer factor and bioaccumulation factor were calculated. The shoot biomass was significantly increased with increasing wastewater exposure, up to four days after the flowering stage. All potentially toxic elements concentrations in belowground (roots and rhizomes) tissues were higher than aboveground (leaves and stems) tissues. Fe showed the maximum concentrations in all organs at different growth stages due to the higher level contents in soil and water. Fe was found to be the least mobile at the reproductive stage and presented in the following order: roots > rhizomes > leaves ≥ stems. By contrast, Zn and Cd metals which are quickly transported in plants exhibited the same trend. Pb was accumulated at the flowering stage as follows: rhizomes > roots > stems > leaves. The toxic threshold was exceeded by Zn, Fe, Cu, and Cd in roots; Fe in rhizomes, and leaves; Cd in rhizomes; and Ni in roots. There was more efficiency in the removal of chemical oxygen demand (61.09%), biochemical oxygen demand (73%), total suspended solids (50%), and ammoniacal nitrogen (59.5%) at the reproductive stage. Therefore, P. australis could be an efficient and valuable tool for the phytoextraction and phytostabilization of metals if harvested at the proper time of growth in high potentially toxic elements polluted coastal ecosystems.

In an attempt to improve the quality of the agricultural drain in Egypt for its reuse again in the irrigation, low-cost solution such as sand filter along with/without other filtration media has been used in this research. As a result of that, pilot plant of sand filter mixed with other filtration media was tested for its ability to improve the sand performance in removing the suspended solids and organic matters from agricultural drain water of the Belbeis drain (in Sharkia governorate in Egypt). Sand only, sand mixed with sponge, sand mixed with activated carbon and sand mixed with ceramic cylinders have been tested to find the best media combination and optimum mixing sand/ medium ratio and optimum infiltration rate. The work has been done on four runs. It was found that sand mixed with ceramic cylinders gave the best removal efficiency with respect to total chemical oxygen demand and chemical oxygen demand for solution which were 77, 74%, respectively, whereas sand mixed with sponge had the best removal efficiency with respect to total suspended solids which was 89%. Also, all tested media combination had effluent quality that complied with Egyptian law 48 for the year 1982 regarding the disposal of wastewater into agricultural drains (chemical oxygen demand ≤ 80 mg/l, total suspended solids ≤ 50 mg/l).

The bacterial diversity in terms of structure and community profile, with special reference to water quality in the wastewater treatment plant of Indian paper industries, is poorly understood. In the present work, characterization of bacterial diversity using 16S (V3-V4 region) rRNA gene amplicon sequencing data with reference to physicochemical parameters in the wastewater treatment plant of two paper industries has been carried out. Amplicon data analysis revealed the presence of bacterial taxa belonging to the phylum such as Bacteroidetes, Proteobacteria, Patescibacteria, Firmicutes, Actinobacteria, etc. Further, taxonomic classification upto genus level and functional analysis data indicated that genera such as Cloacibacterium, Aerococcus, Chryseobacterium, Microbacterium, Acinetobacter, Sphingobium, etc., were involved in the predicted metabolic pathways like carbohydrate metabolism, fatty acid and aromatic compounds biosynthesis as well as degradation. Canonical correspondence analysis confirmed a significant correlation between the microbial pollutions loads and physicochemical parameters. Further, the chemical oxygen demand, biochemical oxygen demand and total suspended solids exceeded the acceptable limits prescribed by Central Pollution Control Board New Delhi, Government of India, for discharge of wastewater. This study finds the correlation between the bacterial community residing in the polluted water of wastewater treatment plant and their environmental preferences. The presence of these bacterial diversity in the wastewater treatment plant of paper industries may affect the maintenance as well as paper quality. In future, it will provide a benchmark for the better understanding and management of wastewater treatment plant in paper industries across the globe.

Due to water scarcity, storage and reuse of water has become a great challenge all over the world. The conventional methods for the wastewater treatment require large capital investment, operating cost, and need trained personal for supervision and maintenance. Therefore non conventional wastewater treatment methods have gained the popularity worldwide. Use of constructed wetland (CW) technology for wastewater treatment is highly efficient since CW are easy to construct, cost effective and increase the aesthetic value. Wetlands behavior and efficiency concerning wastewater treatment mainly depends upon macrophytes, substrate, hydrology, temperature and hydraulic retention time in the system. Present study deals with the removal of pollutants in two stage hybrid subsurface flow CW at different hydraulic retention times (HRT). The domestic wastewater was supplied to CW and treated using the available perennial macrophyte, Arundo donax. The system was run in replicate along with one control. To assess the removal efficiency of the pollutants, parameters like pH, temperature, dissolved oxygen (DO), total suspended solids (TSS), biological oxygen demand (BOD), chemical oxygen demand (COD) and total Kjeldahl nitrogen (TKN) were analyzed at different HRT i.e., 36, 30 and 24 h. The result of the study observed maximum percentage removal of TSS, BOD, COD, and TKN was up to 84.61, 98.37, 61.39 and 91.87% respectively at 30 h of retention time.

Creative solutions to manage stormwater include ecologically based designs, such as biofilter structures. A laboratory experiment was established to study the ability of biofilters to remove nutrients, metals, total suspended solids (TSS), and total organic C originating from roadside stormwater as melted snow. Special attention was paid to the removal of P. In addition, the fate of microplastics (MPs) in the biofilters was followed. The materials selected for biofilters were (a) crushed light-expanded clay aggregates without biochar or amended with biochar, (b) Filtralite P clay aggregates, (c) crushed concrete, or (d) filter sand. A layer to support grass growth was placed above these materials. Stormwater was rich in TSS with associated P and metals, which were substantially retained by all biofilters. Filtralite and concrete had almost 100% P removal, but the high pH had adverse effects on plants. Light-expanded clay aggregates had lower retention of P, and, when mixed with biochar (30% v/v), the leaching of P increased and N retention was improved. None of the materials was ideal for treating both nutrients and metals, but sand was generally best. Vegetation improved N retention and stormwater infiltration. Plant roots formed preferential pathways for water and associated substances, evidenced by the accumulation of MPs along root channels. No MPs were found in discharge. Given the high loading of suspended solids and associated contaminants in snowmelt from traffic areas and their efficient retention in biofiltration, results of this study suggest the implementation of such stormwater management solutions along road verges.

Surface water sources play an important role in human and biological activities and the socio-economic development of the region. Therefore, the assessment of water quality and determination of the causes of water pollution in Sao river is essential for good management of the surface water environment. The study was conducted from July to December 2020. Water samples were collected at the time of low tide to evaluate the water quality indicators of temperature, pH, conductivity (EC), dissolved oxygen (DO), biological oxygen demand (BOD), total suspended solids (TSS), ammonium (N-NH4+), orthophosphate (P-PO43-) and coliform. The source of pollution was determined by direct interviews with households living near Sao river. The results showed that surface water quality in Sao river had signs of organic pollution and microbiological pollution due to BOD, TSS, N-NH4+, P-PO43-, coliform exceeded the allowable limits of National Technical regulation on surface water quality (QCVN 08-MT:2015/BTNMT, column A1). The results of the interview revealed that 70% of respondents said that water was seriously polluted and the main sources of pollution were domestic solid waste and domestic wastewater. Therefore, to improve surface water quality in Sao river, solid waste and wastewater management is urgently required. It is necessary to promote the monitoring and management of water quality with the participation of local authorities and communities.

The demographic and urban expansion of the nineteenth century led to a significant reduction in water resources. One of the considered solutions to this problem was to retain water in reservoirs. Over the years it has been recognized that the construction of small reservoirs can bring greater benefits than large ones. Large reservoirs are not only associated with substantial economic costs, i.e. for the purchase of land, but they also do not sufficiently serve as the components of a flood protection system. They are also of minor importance in the production of so-called ''white energy” (Lehner et al., 2005) and may have a negative impact on the environment. The size and age of reservoirs as well as the type of water dams and their work regime affect the scale of changes in the natural fluvial environment (Robinson et al., 2003). Small reservoirs are a basic element of small water retention, in which water quality depends to a large extent on their location, the way their catchment areas are managed and the functions they perform (apart from typical retention reservoirs). The catchments used for agricultural purposes may be susceptible to accumulation of biogenic substances (nitrogen and phosphorus), and other pollution (Hejduk, 2010; Kanownik et al., 2013; Kasperek et al., 2013; Wiatkowski et al., 2013). The article initially tested the quality of the water in three reservoirs, different period of operation with use of selected indicators. For the purposes of research and this resultant publication, water quality was tested in three reservoirs differing in operating times. It was assumed that the study period covering autumn, spring and early summer was the period with the most visible changes in concentrations of pollutants. Samples taken from the reservoirs were analysed by determining in turn biological oxygen demand (BOD5), ammonia concentration (NH4), phosphate concentration (PO4) and total suspended solids. The use of indicators allowed for assessing the quality of water in these reservoirs and comparing it in terms of different periods of their operation.

Dairy wastewater contains high levels of organic matter that would be a serious threat if being discharged to the environment without any treatment. This study investigated the influence of various parameters including the concentration of poly aluminum chloride (PAC) on the chemical coagulation process and the concentration of H2O2, pH of the solution, reaction time, voltage and distance of electrodes in the electro-Fenton (EF) process. The optimum conditions obtained in this study included PAC concentration of 100 mg/L, pH of 3, reaction time of 60 min, voltage of 20 V, H2O2 concentration of 1.5 g/L and electrode distance of 2 cm. This resulted in the removal efficiency of 90.3%, 87.25%, and 87% for chemical oxygen demand (COD), biochemical oxygen demand (BOD5), and total suspended solids, respectively. The estimated cost of the process in terms of 1 kg COD removal was about $1.16. Two experimental models, called the feed-forward artificial neural network (FF-ANN) and partial least squares (PLS), were developed to predict the behavior of the process in COD removal. The results confirmed that both FF-ANN and PLS were powerful tools in predicting COD removal in the EF process, as the correlation coefficients between the predicted COD and the actual COD for the PLS and FF-ANN models were 0.854 and 0.971, respectively. Sensitivity analysis of both models showed that the reaction time and electrode distance had the most influence on the output of PLS and FF-ANN, respectively. Therefore, this combined process can be regarded as a thought-provoking one for dairy wastewater treatment, and the FF-ANN model was a more powerful tool than the PLS one.

Pollution caused by swine wastewater is a growing concern in many countries. In the developing countries, swine wastewater is not properly collected and treated, the wastewater from swine farm pollutes the ecosystem. Especially for small swine farms, they could not afford to have wastewater treatment system. Therefore, farmers need cheap, sustainable technology for future mixed farming. Vermifiltration by earthworm has been introduced to be an answer for enhancing wastewater treatment. Vermiwash is the liquid gathered from vermicomposting that has high microbial activities and nutrients. This study was carried out on a small pilot scale to investigate swine wastewater treatment efficiency of vermifiltration system with and without vermiwash and compared with the geofiltration system. Vermiwash was incubated in vermifiltration and geofiltration systems for 1 week before the treatment. The result showed improved efficiency of vermifiltration incubated with vermiwash in swine wastewater treatment for biological oxygen demand (BOD), chemical oxygen demand (COD) and total suspended solids (TSS) removal, which was highest followed by vermifiltration without incubated vermiwash, geofilter incubated with vermiwash and geofilter, respectively. Good performance of vermifiltration incubated with vermiwash compared with the geofilter treatment was demonstrated for removal of BOD (91.29 ± 9.89%, n = 10), COD (91.42 ± 6.34%, n = 10) and TSS (86.02 ± 10.45%, n = 10). Furthermore, the burrowing activity of the test earthworm (Eisenia fetida) promoted the aeration condition in vermifilter which led to more dissolved oxygen (DO) in effluent (61.28 ± 20.05%, n = 10). Moreover, the amount of copper (Cu) in effluent was decreased compared with influent by up to 88% in all treatment. After 10 weeks of the experiment, the vermicompost that was incubated with vermiwash and produced from earthworm on the top layer was analyzed and showed that nutrients (nitrogen, phosphorus) and soil organic carbon were increased with vermifilter treatment (47.65, 81.61 and 31.79%, respectively) compared with geofilter treatment. In addition, bioavailability of Cu in soil in form of exchangeable Cu was decreased by increasing the bound to organic matter fraction. Transformation of Cu during vermifiltration happened and alleviated the mobility and availability of Cu. Copper in exchangeable form can change into non-toxic form. Therefore, vermifiltration process incubated with vermiwash could reduce the dispersion of copper in swine waste. In conclusion, vermiwash could enhance performance of vermifiltration for swine farm wastewater treatment. The available fraction of copper in vermicompost produced from vermifiltration decreased. Therefore, the farmer could produce vermicompost as the biofertilizer for agricultural production. Using vermifiltration for wastewater treatment in small swine farm could be the eco-solution for nutrient recovery, water resource recycles and minimize pollution.

Climate change is projected to have a major impact on agricultural water resources availability. Comprehending the effects of climate change on water supplies for agriculture is an essential aid for the effective management of available water resources. A forecasting model, a surface water quality model coupled with an optimization algorithm have been used in forecasting agricultural water quality and to maximize the reuse of wastewater in the Osan watershed, South Korea. In forecasting water quality and streamflow parameters for a 30 year period, AutoRegressive Integrated Moving Average (ARIMA) was used. Both ARIMA model fit and model performance were within accepted levels. Water quality and quantity were simulated using the QUAL2Kw model. Jaya algorithm was executed to optimize the process for determining optimal quantities for agricultural drainage water (ADW) reused at withdrawal points. Simulations of water quality show that organic matter levels are key attributes in the management of the Osan drain. QUAL2Kw model calibration and validation show that the model can be applicable with values of Nash—Sutcliffe model efficiency (NSE) > 0.5 respectively. Water quality results show that Biochemical Oxygen Demand (BOD), Dissolved Oxygen (DO), Total Nitrogen (TN) and Total Suspended Solids (TSS) were within acceptable ranges. ADW is suitable for indirect irrigation in the Osan watershed as water quality standards meets Korea’s standards and Food and Agricultural Organization (FAO) Guidelines. Irrigation water demand will increase by 47.1 % for summer and by 16.5% for winter by 2050 due to an increase in temperature. The total agricultural ADW reuse amounts will increase by 47.4% for summer and 17.5% for winter by 2050 due to the creation of farmlands, as there will be an increase in food demand. Optimization results show that drainage water availability will increase by 31.6% and 21.3% respectively for summer and winter by 2050 due to climate change effects. Overall, the results show that the reuse of ADW demand and the available amounts is most likely affected by climate change.

This paper reports long-term performance of a two-stage AMX® system with a capacity of 70 m3/d treating actual reject water. An air-lift granulation reactor performed partial nitritation (PN–AGR) at an average nitrogen loading rate (NLR) of 3.1 kgN/m3-d, producing an average effluent –N/NH4+–N ratio of 1.04. The average nitrogen removal rate of the system was 3.91 kgN/m3-d following an anaerobic ammonium oxidation (Anammox) stage moving bed biofilm reactor (A–MBBR). Although the total nitrogen concentrations in the reject water fluctuated seasonally, overall nitrogen removal efficiency (NRE) of the two-stage AMX® system was very stable at over 87%. The two-stage AMX® system, consisting of a PN–AGR followed by an A–MBBR, operated at a stable NLR of 1.86 kgN/m3-d (1.64 kgN/m3-d including the intermediate tank), which is 1.8 times higher (1.6 times including the intermediate tank) than other commercialized single-stage partial nitritation/Anammox (PN/A) processes (which operate at a NLR of about 1 kgN/m3-d). The PN–AGR was affected by high influent total suspended solids (TSS) loads, but was able to recover within a short period of 4 days, which confirmed that the two-stage PN/A process is resilient to TSS load fluctuations.

Water bodies are critical in maintaining and sustaining ecosystems. However, urban water bodies are often ignored during development projects, and comprehensive plans for their revival and rejuvenation are not seen as priorities. This paper describes the rejuvenation project for a dry water body at Rajokri, Delhi, India. A "scientific wetland with active biodigester" (SWAB) system was developed to treat domestic wastewater, which was then used to fill the lake. The SWAB effectively removed about 89% removal of oil and grease, 86% biological oxygen demand (BOD), 85% chemical oxygen demand (COD) and 86% of total suspended solids (TSS) when the respective inlet concentrations were 18 ± 1.14 mg/L, 124 ± 2.9 mg/L, 480 ± 11.9 mg/L and 116 ± 1.82 from the raw wastewater. The SWAB system provides completely natural treatment with zero electrical consumption. The revival of the water body using a decentralized wastewater treatment system has immensely helped in management of urban wastewater, ground water recharge and enhanced ecosystem and biodiversity values. The project demonstrates the integration of socio-cultural, societal, ecological, ecosystem and technological aspects for the revival of the lake.

Universiti Malaysia Sabah (UMS) campus in Kota Kinabalu consists of a large detention pond that stores the stormwater and limits the outflow rate into Likas' estuary. It is no doubt the detention pond has been designed per the Urban Stormwater Management Manual (USMM) requirement in terms of quantity control, however rapid development and changes in surrounding landscapes may affect the water quality. This study investigates the stormwater quality from the UMS detention pond and drainages within the campus. Water sampling was primarily taken during the dry period to justify worst-case scenarios without dilution from the rainfall season. Then the water quality parameters were tested using standard laboratory procedures mainly for Biochemical Oxygen Demand (BOD), Ammoniacal Nitrogen (AN), and Total Suspended Solids (TSS) with a minimum of a triplicate experimental run at the Environmental Laboratory, Faculty of Engineering, UMS. The determined water quality was compared with the National Water Quality Standards (NWQS) from the Department of Environment Malaysia. Overall the stormwater quality obtained for Dissolved Oxygen (DO), Chemical Oxygen Demand (COD), AN and pH is within Class II to III, which is slightly polluted. However, the TSS from ponds near to main road and construction areas exceeds Class IV, indicating polluted conditions. There is a slight increase for BOD and AN parameters when comparing samples between June 2020 (post-MCO) and January 2017, which was suspected briefly due to fertilizing work for the campus landscapes. Although the TSS value is low, the TSS volume would increase over a period, raising the temperature while reducing the DO concentration and endanger the aquatic species and the ecosystem. Hence, it is recommended for a future study to emphasize TSS value as it would contribute significantly in designing sustainable stormwater management, particularly for the stormwater treatment, such as when optimizing for the utilization of alternative filter media, which reduces the maintenance and increasing the lifespan of the system.

The discharge of chromium into the environment has become a problem of great concern all over the world including Pakistan for a few decades. The present research was conducted to study the bioremediation effect of carbon-activated granules (CAAGs) of two algal strains as a novel biosorbent for chromium from tannery effluent in addition to improvement of different water quality indicators. Effect of sorbent dose (5, 7 and 9 g L−1) and contact time (0–140 h with interval of 20 h) on chromium removal was evaluated. Maximum chromium removal (9.33 mg L−1 and 7.60 mg L−1) from raw tannery wastewater (WW) was reached after 120 h using 9 gL−1 of Chlorella vulgaris and Scenedesmus obliquus biomass, respectively. Rate of Cr removal was found directly proportional with dose of granulated algae and incubation period. Carbon-activated granules of Chlorella vulgaris as a biosorbent (9 g L−1) exhibited 19.47% more chromium removal in 10 times diluted WW compared to raw WW. The CAAG of both isolates reduced COD (38.08% and 34.72%), BOD (37.04% and 13.60%) and TSS (34.01% and 36.30%) for Chlorella vulgaris and Scenedesmus obliquus, respectively. Meanwhile, both CAAG types decreased TSS by around 85% while resulting in a slide increase in pH compared to initials. The CAAG of both isolates proved to be promising candidates for environmental bioremediation by reducing chemical and biological oxygen demand and total suspended solids of tannery WW by developing cost-effective and ecofriendly process in the prevalence of sunlight.

This study aims to find the most accurate machine learning algorithms as compared to linear regression for prediction of fecal coliform (FC) concentration in the effluent of a multi-soil-layering (MSL) system and to identify the input variables affecting FC removal from domestic wastewater. The effluent quality of two different designs of the MSL system was evaluated and compared for several parameters for potential reuse in agriculture. The first system consisted of a single-stage MSL (MSL-SS), and the second system consisted of a two-stage MSL (MSL-TS). The concentration of FC in the effluent of the MSL-TS system was estimated by three machine learning algorithms: artificial neural network (ANN), Cubist, and multiple linear regression (MLR). The accuracy of the models was measured by comparing the real and predicted values. Significant (p

The impact of hydraulic loading rate (HLR) and hydraulic retention time (HRT) on the bioremediation of municipal wastewater using a horizontal flow constructed wetland (HFCW) vegetated with Cyprus papyrus was investigated. Three different HLRs were applied with values of 0.18, 0.10 and 0.07 m3/m2.d with corresponding HRT of 1.8, 3.2 and 4.7 days. The flow rate was 8.3 m3/d and the average organic loading rate was 0.037kg BOD/m3/d. Results showed that the performance of HFCW is linearly affected by decreasing HLR and increasing the HRT. The remediation for the heights HRT (4.7) days and lowest HLR (0.07 m3/m2.d) produced high quality effluent in terms of reduction of chemical oxygen demand (COD; 86%), biochemical oxygen demand (BOD; 87%) and total suspended solids (TSS; 80%) as well satisfactory nutrient removal. Also, removal of 2-3 logs of bacterial indicators was achieved. The dry biomass of Cyprus papyrus was 7.7 kg/m2. Moreover, Cyprus papyrus plant proved to be very efficient in nitrification processes due to high diversity of the roots that increase the treatment surface area.

The effect of the lockdown imposed to limit the spread of SARS-CoV-2 in France between March 14 and May 11, 2020 on the wastewater characteristics of two large urban areas (with between 250,000 and 300,000 inhabitants) was studied. The number of outward and inward daily commuters was extracted from national census databases related to the population and their commuting habits. For urban area A, with the larger number of daily inward commuters (110,000, compared to 53,000 for B), lockdown was observed to have an effect on the monthly load averages of chemical oxygen demand, biochemical oxygen demand, total Kjeldahl nitrogen, total suspended solids and total phosphorus, all of which decreased (confidence level of 95%). This decrease, which varied between 20% and 40% and reached 45% for COD, can be related to the cessation of catering and activities such as hairdressing, which generate large amounts of graywater. The ammonium loads, due to the use of toilets before leaving for work and after returning from work, remained constant. In the case of urban area B, lockdown had no noticeable effect. More data would be necessary in the long term to analyze the effect of changes in the balance between ammonia and carbon sources on the operation of wastewater treatment plants.

RESUMO A quantificação de biomassa fixa em reatores de leito móvel com biofilme (MBBRs) é essencial para avaliação e controle do desempenho deles. Entretanto, observa-se que tal quantificação é realizada empregando-se diversas técnicas, o que dificulta comparações entre resultados. No presente trabalho, foram testadas duas das principais técnicas (agitação mecânica e ultrassom) utilizadas para extração de biomassa aderida aos meios-suporte (mídias) de um MBBR sem utilização de agentes químicos. Os desenhos experimentais foram realizados utilizando-se planejamento fatorial completo, e, para tal, foram selecionadas duas variáveis independentes: tempo (T) de exposição de 15 a 60 min; e volume de água destilada utilizado para extração (V) de 100 a 400 mL. O ultrassom mostrou-se superior à agitação mecânica quanto à eficiência no percentual extraído de sólidos suspensos totais (%SST), e embora nenhuma das variáveis (T ou V) tenha contribuído significativamente nas faixas testadas, com base na superfície de respostas, foi conduzido um novo experimento, ampliando a faixa de T de 5 a 90 min. A variável T contribuiu significativamente para o %SST, e o melhor resultado foi obtido com T = 90 min. Recomenda-se o uso de ultrassom, volume de mais fácil manuseio (250 mL) e T = 90 min. Ensaios adicionais são recomendados, tendo em vista a padronização do método. ABSTRACT Quantification of attached biomass in Moving Bed Biofilm Reactors (MBBR) is essential for performance assessment and process control. However, it is observed that such quantification is performed using the most diverse techniques, which hampers comparisons between results. In this investigation, two of the main techniques used (mechanical agitation and ultrasound) were compared for removal of the biomass attached to the support media of an MBBR reactor without the use of chemical agents. The experiments were planned following full factorial designs using the two independent variables: Exposure time (T) from 15 to 60 min; and Volume of distillate water used for extraction (V) from 100 to 400 mL. The results revealed that ultrasound is superior to mechanical agitation regarding detachment of the total suspended solids (%TSS) and though neither T or V contributed significantly within the interval tested, based on the response surface, a new experiment was performed using an increased T range from 5 to 90 min. Then, exposure time contributed significantly to the %TSS detachment, with the best result at 90 min. The use of ultrasound is therefore recommended, with volume that is easier to handle (250 mL) and time equal to 90 min. Additional tests are recommended for method standardization.

This study aimed to evaluate water quality in the canals in Ninh Kieu district, Can Tho city in the period of 2018-2019. Monitoring data were collected at 10 locations distributed on Tham Tuong canal (TT1, TT2), Cai Khe canal (CK1-CK4), Bun Xang lake (BX1-BX2), Cai Son - Hang Bang canal (HB1, HB2). Water quality parameters assessed include temperature, pH, turbidity, total suspended solids (TSS), biological oxygen demand (BOD), chemical oxygen demand (COD), orthophosphate (PO4 3--P), nitrate (NO3 -- N), ammonia (NH4 +-N), nitrite (NO2 -- N) and coliforms. The results showed that water quality in the canals in Ninh Kieu district, Can Tho city were contaminated with coliforms, TSS, BOD, and COD. The temperature and pH parameters were very little fluctuated, while BOD, coliforms, and DO tended to decrease in the period from 2018-2019. Particularly, the mean P-PO4 3- in 2019 was higher than that in 2018. BOD, COD, TSS, P-PO4 3-, and coliforms in Tham Tuong canal were higher than those in other water bodies because several production and business activities are taking place. Water pollution problem in Ninh Kieu district, Can Tho city needs to be solved as soon as possible to ensure healthy environment, attracting tourists to visit in Can Tho city. Keywords: water quality, pollution, microorganisms, organic matters, suspended solids, Ninh Kieu, Can Tho

The purpose of this study was to evaluate the performance of individual units of waste stabilisation ponds (WSPs) system treating domestic wastewater. The study was conducted by measuring the concentrations of physiochemical parameters and bacteriological indictors in the influent and effluent samples of each pond. The thickness of sludge was determined by measuring depths of sludge layer in each pond. Knowing the performance of each pond will speed up targeted intervention to improve performance. The influent was mainly characterised by 224, 500, 270 mg L⁻¹, 258 Nephelometric Turbidity Unit (NTU) respectively, of biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), turbidity and 35600 coliform forming units/100 ml of faecal coliforms. Bacteriological counts were fluctuating and effluent faecal coliforms counts were 1.22 × 10⁴ ± 2.0 × 10² coliform forming units/100 ml. The hydraulic retention times (HRTs) decreased by 2.0, 13.6 and 7.2 days in the first three ponds and by 3.3 days in the last three ponds. Biochemical oxygen demand in the final effluent was 40 mg L⁻¹ more than the design value of f 25 mg L⁻¹. Chemical oxygen demand in the final effluent was 190 mg L⁻¹, higher than the prescribed limit of 150 mg L⁻¹ of discharge into rivers. Total suspended solids in the final effluent was 150 ± 127 mg L⁻¹ more than the national limit of 25 mg L⁻¹. Total suspended solids and turbidity correlated positively with bacteriological indicators, but there was no correlation with temperature except with faecal coliforms. There was also no correlation observed between suspended solids and pH. The treatment system did not meet the design treatment criteria because of overloading as a result of increased population which exceeded the design value. The final effluent from the system did not meet the discharge limits, therefore, it is unsuitable for discharge into the environment as it can pollute ground and surface waters as well as the open environment. Knowledge on the performance of each pond will help in proper interventions to be undertaken at the targeted pond or unit. It is therefore eminent to desludge each pond as a short‐term solution and expand the system for a long‐term solution.

Domestic wastewater entering the wastewater treatment plant (WWTP) of Kerkennah (Tunisia) contains high organic load and high salinity. The biological treatment of these influents with conventional microorganisms has proven to be not very effective, which might be improved by functionally selected halotolerant/halophilic heterotrophic bacteria. Therefore, a laboratory-scaled activated sludge reactor (ASR) was used for a continuous treatment of this wastewater. The performance of the ASR, inoculated with a mixed culture of active biomass gradually acclimated to the wastewater, was evaluated in terms of carbonaceous pollutant removal efficiency. Experiments were conducted at different organic loading rates (OLRs, varying from 250 to 1200 mg chemical oxygen demand (COD)/l.d). The descriptive analysis showed that the removal efficiency (r) of the ASR was high, peaking at 95% for CODr in medium OLRs, and up to 99% for Biological oxygen demand (BODr) and total suspended solids for high OLRs and salinity. The overall removal efficiency was improved by 1/3th or more compared to the WWTP by these selected and acclimated bacteria. The different observations were combined in an innovative statistical design of Hierarchical clustering. This method improves on traditional approaches by allowing flexibility in understanding the complex variations within the WWTP and the ASR. The identification of the bacterial biomass responsible for high BODr in the ASR by conventional microbiology demonstrated the dominance of Proteus mirabilis and Aeromonas hydrophila. The 16S rRNA gene gave a more accurate identification, indicating a great bacterial diversity and the possibility of a new species.

Domestic wastewaters causing pollution contain inorganic and/or organic materials. When the domestic wastewater outflows to the receiving waters, it causes physical, chemical, and biological pollution in them, and deteriorates the ecological balance of those waters. In the treatment of wastewater, various treatment methods are available depending on the pollution strength of the wastewater. Besides mechanical and biological methods, wastewater treatment with physicochemical methods is still one of the most effective and economical options. Particularly in wastewater with a high concentration of suspended solids, this method is very successful, and obtaining high suspended solids removal efficiencies is very possible. In this study, the effects of the use of coagulant and coagulant aid to be used in a treatment plant where domestic wastewater treatment is carried out are determined to increase the treatment efficiency of a biological treatment that comes later in the stages of the treatment. The effluent of the pre-settling tank may contain a lot of suspended solids. This presence of excess suspended solids decreases the efficiency at other levels of treatment and causes energy loss. In the experiments, the standard jar and inhibition tests are done as a method. As a result of the conducted studies, it is determined that the FeCl3, Synthetic coagulant LP 526, FeClSO4, and the combination of anionic polyelectrolyte yield the best results in the removal of the parameters of chemical oxygen demand (COD), total suspended solids (TSS), and volatile suspended solids (VSS). While FeCl3, APE 65, APE 85, Synthetic coagulant LP 526, and FeClSO4 did not show any inhibition effect in the sludge, APE 67, CPE 84, and (Al-2(SO4)(3) are found to cause inhibition in the sludge. Research Fund of Istanbul UniversityIstanbul University [BYP-2017-23291] Financial support from the Research Fund of Istanbul University, Project number BYP-2017-23291.

Measurement and prediction of wastewater quality parameters are crucial for evaluating the risk to the receiving waters. This study presents new methods for the identification of outlier data and smoothing as an effective pre-processing technique prito to modelling. This new data processing method uses a combination of the autoregressive integrated moving average (ARIMA) model and -the adaptive neuro fuzzy inference system with fuzzy C-means clustering (FCM) (ANFIS-FCM). These new pre-processing methodsare compared to previously employed non-linear approaches for modelling of wastewater influent/effluent 5-day biochemical oxygen demand (BOD(5)), chemical oxygen demand (COD) and total suspended solids (TSS). Linear modelling of each parameter, 242 linear models, were investigated, and a linear model for each parameter was selected. The results of the non-linear models led to an acceptable prediction for qualitative parameters so that the high coefficient of determination (R(2)) was observed for the influent and effluent BOD and TSS, respectively. The range of the R(2) for all models was recorded as 0.8–0.87 and 0.83–0.89, respectively. By a combination of the linear and non-linear mothods a hybrid model was introduced. The proposed hybrid model for the influent BOD with the highest correlation between the observed and predicted values, and limited scattering was identified as the optimal model (R(2) = 0.95). The use of hybrid models to predict wastewater quality parameters improved the performance and efficiency of the models. In addition, a comparison of the hybrid model with the recently developed models in the literature indicates that the developed ARIMA-ANFIS-FCM outperformed other models.

This article presents an environmental and energy analysis of a wastewater treatment plant operating on sequential batch reactor technology. The analysis of energy consumption shows that the electrical, mechanical, chemical, and human energy consumption works out to 0.26 kW h/m3 of the treated wastewater. The overall share of electrical energy consumption is 84%, and 15% share is of mechanical energy. Nearly 78% of the electrical energy is consumed in the aeration process. The biological oxygen demand, chemical oxygen demand, total suspended solids, total nitrogen, and total phosphorous are measured for the influent and effluent of the treatment plant. A reduction of 76–97% occurs in these parameters due to wastewater treatment. The greenhouse gas emissions arising directly from the treatment processes and indirectly from the electricity and diesel usage are estimated. The direct and indirect emissions from the wastewater treatment plant amount to 105 tCO2e/year and 1316 tCO2e/year, respectively. A projection of methane accumulation in the atmosphere from this plant till the year 2041 is also made. The contribution of this plant to the atmospheric accumulation of CH4 is projected to reach 8679 kg in 2029. The projection for 2030 and thereafter is 9468 kg. Analysis of the energy, environment, and wastewater treatment nexus is of significance to have a holistic view for the sustainable development.

The tanning industry causes great damage and pollution to the environment. It generates tanning effluents and solid waste which, without pretreatment, discharged directly into the environment. Beam-house operations are among the important process of this industry which generates the biggest amount of toxic effluents. These wastes are considered as the most odious materials in the leather industry. The effluent is characterized by alkaline pH value, high loads of oil&grease, sulfides, total suspended solids, chemical oxygen demands and biological oxygen demands. Integration of chemical coagulation using ferric chloride aided with lime and down flow hanging non-woven (DHNW) reactor was applied in the present study. Coagulation was performed using a continuous coagulation reactor (CCT). The DHNW was packed with non-woven poly ethylene terephthalate (PET) fabric produced from waste plastic bottles. The efficiency of the integrated treatment system was assessed using the reduction of sulfide, chemical and biological oxygen demands (COD & BOD), total Kjeldahl nitrogen (TKN) and total suspended solids (TSS). Residual concentrations of COD, BOD and TSS in the CCT effluent were 985, 440 and 25 mg/L (96.1%, 85.2% and 99.3% removal), respectively. The effluent of CCT reactor was feed to the DHNW reactor. Concentrations of COD, BOD and TSS were 145, 55 and 4 mg/L, respectively in the final treated effluent. While, the sulfide concentration had been greatly reduced to 0.5 mg/L. With respect to the parameters studied, the treated effluent might meet the National regulatory standards for discharging into the sewerage systems.

Phytoremediation method, in combination with porous concrete and some additives, has been examined in order to reduce the contamination of unconventional water resources. This treatment system is economically cost-effective and easy to apply, compared to other treatment methods. The current study was focused on evaluating the effects of arrangement of vetiver grass and porous concrete specimens (four types of grass-specimens arrangements), vetiver grass layout on polystyrene sheets (5 × 5 and 10 × 10 cm spacing), porous concrete mixture (basic design as control, basic design + 5% zeolite, basic design + 10% zeolite, basic design + 5% pumice), temperature of the test room (10 ± 2, 20 ± 2 and 30 ± 2 °C), type of the unconventional water (domestic wastewater effluent and urban runoff) and Portland cement type (2 and 5) on the reduction of biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), and fecal coliforms. Taguchi method (robust design) and Qualitek-4 software were used to optimize the combination of aforementioned factors. Results indicated that temperature was the most effective parameter on reducing the BOD, COD, and fecal coliforms. The vetiver grass layout on the polystyrene sheets and porous concrete mixture design were more effective than vetiver grass-porous concrete arrangement. Effect of vetiver grass roots was significant in reducing the TSS content. The cement type had minimum impact on reducing the qualitative parameters of the wastewater samples. Based on the results, combination of 10 × 10 cm spacing of vetiver grass on polystyrene sheets, third type of vetiver grass-porous concrete arrangement, porous concrete mixture with 10% zeolite, Portland cement Type 2, and room temperature of 30 ± 2 °C was the best for improving the quality of wastewater effluent as compared to urban runoff. The treated effluents can be used with caution for urban green spaces or irrigation purposes, and the difficulties of the proposed combined system should be taken into consideration.

This study evaluates the bio-treatability performance and kinetic models of full-scale horizontal subsurface flow constructed wetland used for the tertiary treatment of composite industrial effluent characterized by high-salt content ranging from 5830 to 10,400 µS/cm and biochemical oxygen demand (BOD5): chemical oxygen demand (COD) ratio below 0.2. The wetland vegetated with Phragmites australis was operated in a semi-arid climate under an average hydraulic loading rate of 63 mm/d. The results of a 4-year operation calculated based on the concentration of pollutants showed that the average removal efficiency of COD, BOD5, and total suspended solids (TSS) were 17.5, 5.1, and 11.2%, respectively. The system reduced up to 6.5 ± 0.7% of electrical conductivity presenting poor phyto-desalination potential without considering the contribution of evapotranspiration in water balance in contrast to satisfying performance for heavy metals reduction. The comparison of the kinetics of organic matter removal obtained by the first-order and Monod models paired with continuous stirred-tank reactor and plug flow regime showed that Monod-plug flow model provided the best fit with the constants of 2.01 g COD/m2·d and 0.3014 g BOD5/m2·d with the best correlation coefficient of 0.610 and 0.968 between the predicted and measured concentrations, respectively. The low kinetic rates indicate that the process is capable of effluent polishing instead of purification due to the presence of organic compounds recalcitrant to biodegradation and a high level of salinity.

Higher standards in the European Water Framework Directive and national directive demand advanced wastewater treatment for removal of nutrients and organic micropollutants before the discharge into water bodies. Systematic investigations regarding relative dosage and filtration processes for removal of flocculated solids are currently lacking. In this study, the performance of technologies for advanced removal of total phosphorus down to 5 mol Me3+/mol sRP was necessary to achieve soluble reactive phosphorus (sRP) concentrations of

The drip irrigation emitter is a small mechanical device which is designed to dissipate pressure and constantly discharge a small, uniform flow of water. Partial and total clogging of emitters is closely related to the quality of the irrigation water. Physical factors for water quality include all inorganic materials such as sand, silt and clay; the filtration of the irrigation water is essential in order to avoid blockages damage of the small passage emitters, drippers, sprayers and sprinklers. This is a mechanical water treatment and it is achieved by the installation of main filtering devices (filters) at the control head of the irrigation systems. Sand–gravel media filters are particularly suitable for water with high suspended solid content. The precision agriculture database generally includes irrigation facilities, water availability and planning of other inputs. The science of remote sensing RS is usually restricted to methods that detect and measure electromagnetic energy including visible and non-visible radiations that interact with surface materials and the atmosphere. A new multispectral optical sensor system has been designed and developed for measuring total suspended solid (TSS) concentration in polluted water. In this study, the optical sensing system has been designed for measuring scattered radiation from water samples from media filters at the irrigation systems. This study aims to measure the peak of optical properties at transmission and absorption intensities of irrigation water samples. Three different concentration levels of TSS are 286.8, 270 and 290 mg/l. It was noticed that high values were 4240 and 3880 for absorption intensities to Zaffaran media and Misr bank media at wavelength 632.8 nm.

Expansion of subsurface drainage into forage production may have a deleterious effect on surface waters due to increased nitrogen and phosphorus loading. The impact of controlled subsurface drainage (CD) on nitrogen and phosphorus loss compared with free subsurface drainage (FD) in tile drainage water has been explored to a lesser extent from forage production systems. This study quantifies the effects of CD and FD on average seasonal concentrations and cumulative loads of the total suspended solids (TSS), nitrate nitrogen (NO3 -N), and dissolved reactive phosphorus (DRP) in subsurface drainage water from a poorly drained floodplain soil in a cereal rye (Secale cereale L.)-sorghum [Sorghum bicolor (L.) Moench] rotation with rotational cattle grazing. During all crop seasons of sorghum production (2010-2013), CD had 6.03-9.63 mg L-1 less NO3 -N than FD. Mean DRP concentration was significantly higher for CD than for FD during all seasons except for sorghum in 2012-2013. Average cumulative discharge was 38 and 314 m3 ha-1 less for CD than for FD during sorghum and cereal rye growing seasons, respectively. Controlled drainage had 0.68-6.14 kg ha-1 lower cumulative NO3 -N loads than FD. The DRP loads were dependent on discharge. During sorghum growing seasons, TSS and DRP loads were 79-90% lower in CD compared with FD. The ability to reduce drainage water flow from tiles and subsequent nitrogen and phosphorus loading with CD compared with FD in a floodplain soil indicates that CD can be effective best management practice for forage production systems.

Wastewater treatment in semi-natural systems, such as a hydroponic lagoon operating as the third stage of purification, is becoming more and more popular because of the efficiency of nutrient removal. Very often treatment processes in hydroponic ditches are supported by algal growth, which can cause an increase in the concentration of total suspended solids in the outflow from the wastewater treatment plant. The aim of this study was to analyse changes in the granulometric composition of particles in the hydroponic lagoon operating as the third stage of wastewater purification in a municipal wastewater treatment plant (WWTP) in Poland. Measurements of the particle sizes were made with the use of the laser diffraction method. The results showed that the size of the particles in the hydroponic lagoon varied from 0.01 to 1000 μm. Analyses of the average diameters D(3.2) and D(4.3) showed that particles have low reactivity but good sedimentation properties and their fractal dimensions are usually higher than 2.0, which indicated that they had well-developed surfaces. Most of the particles flowing out of the WWTP were probably algae or particles that could adsorb other pollutants onto their surfaces. The use of laser granulometry for particle identification might be useful in characterizing the total suspended solids as well as helping to develop cheaper and more efficient methods for its removal.

In Arequipa (Peru), a small-scale tannery industry cannot afford costly or complicated methods for effluent treatment. In this work, we designed and tested a bubble column bioreactor for tannery effluent treatment based on the native filamentous fungi Penicillium citrinum and Trichoderma viride. The bioreactor construction used low-cost materials, with an easy-to-handle design. The parameters considered for testing were based on current Peruvian legislation. In the bioreactor, P. citrinum successfully reduced the effluent content of sulfides, chemical oxygen demand (COD) and total suspended solids (TSS) and removed nearly 80% of the chromium (VI) after 120 h of reaction. The resulting treated effluent had a composition within the maximum limits permitted by Peruvian legislation. Trichoderma viride also reduced the content of TSS, COD and sulfides, but decreased the chromium (VI) concentration by only ~ 20% after the same reaction time. Both filamentous fungi were able to grow in the experimental conditions used and the bioremediation process occurred with no significant alteration in pH. These findings indicate that a bubble column bioreactor using P. citrinum as a bioremediator agent provides low-cost, effective technology for treating effluent waste produced by artisanal and small-size tannery factories in the region of Arequipa.