There is great competition to improve the performance of membranes for water treatment within the scope of the research, especially the problem of biofouling on the membrane as it is related to the performance and life of the membrane. This study introduces a new mixture of hybrid bioreactor membranes that combine oxidized multi-walled carbon nanotubes (OMWCNTs) with polyethersulfone (PES) using a phase inversion method, along with equal proportions of zinc oxide nanoparticles (ZnO NPs) and Arabic gum (AG) from an acacia tree, for application in a submerged membrane bioreactor to treat wastewater for a dairy product at the College of Agriculture / Baghdad University. The results when comparing the nascent composite membranes (PES / OMWCNTs / ZnO / AG) with that of (PES / OMWCNTs) indicated that the membrane mixed with ZnO / AG has more hydrophilic (16%) As well as reducing the negative charge on the surface of the membrane almost three times, As evidenced by the water contact angle test and the zeta potential data respectively, furthermore, the atomic force microscopy analysis showed that this improved membrane showed lower values of surface roughness (by 46.8%), and more flexible normal flux values (by almost doubling), Moreover, the rate of rejection increased when the bovine serum albumin (BSA) solution was passed a percentage (13%) when compared with PES / MWCNTs membrane. Importantly, the prepared membrane also presented removal efficiency of chemical oxygen demand (COD) was significantly 37.5% higher when compared with the commercial MBR system.

A pot experiment was carried out in the green house of Bangladesh Jute Research Institute (BJRI), Dhaka to study the response of jute (Corchorus capsularies and Corchorus olitorius) to the accumulation of As from soil to plants when various rates of As were applied. In the experiment, four treatments of arsenic (control, 10, 20 and 40 mg/kg) were applied. The salt sodium meta-arsenite (NaAsO2) was used as a source of As. Three jute varieties of CVL-1, 0-9897 and OM-1 were used.  CVL-1 variety is As sensitive whereas the 0-9897 and OM-1 varieties appeared to be As tolerant and OM-1 takes up the highest amount of As. Arsenic will be ingested into the body exceeding the maximum allowable daily limit (0.22mg/kg per day) through the consumption of 100g of jute leaves of these three varieties per day. Accumulation of As at 10 and 40 mg/kg treatment, the maximum was observed at 52 days harvest for CVL-1 while for the other two treatments, the maximum was observed at 42 days of growth. In the case of 0-9897 and OM-1 varieties, overall the maximum accumulation of As was observed at 42 days of growth at 40 mg/kg treatment.

A green approach was employed to fabricate ZSM-5 zeolite from expanded perlite and reduced graphene oxide (rGO) in the presence of the synthesized ZSM-5 zeolite to produce ZSM-5@rGO composite by one-step synthesis process via hydrothermal treatment. ZSM-5@rGO composites were characterized by various techniques such as scanning electron microscopy (SEM),  X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, Raman spectroscopy, and N2 desorption–adsorption. The results showed that ZSM-5@rGO composite have a large surface area, uniform distribution and orderly crystal form. Moreover, the synthesized composites were evaluated as an adsorbent for removing cationic dye, methylene blue (MB), from an aqueous solution. The influence of factors on the adsorption, such as adsorption time, adsorbent dosage, initial dye concentration, and pH of solution, were investigated. The results of isothermal adsorption showed that the adsorption process was fit for both Langmuir and Freundlich models, and the highest adsorption capacity of ZSM-5@rGO composite for MB dye was 95.87 mg/g at environment temperature (30 oC). In addition, the study of adsorption kinetics indicated that the adsorption was consistent with the pseudo-second-order kinetic model with correlation coefficients of 0.9962. From these results, it can be confirmed that ZSM-5@rGO composite uses silicoaluminate as economical starting material with relatively high adsorption capacity and removal efficiency, which is a promising application for treating wastewater on a large scale.

Fat, oil, and grease (FOG) deposits in the urban sewer system affect the optimal performance of the wastewater collection system and treatment plant, while increasing sewer maintenance costs. The interaction of microplastics (MPs) and FOG in the sewer system could drastically change the quality of deposited materials and the fate of MPs in raw sewage. In this study, the batch experiment was conducted to explain the mechanism of FOG formation by synthetic wastewater and its interaction with polystyrene (PS) and polymethyl methacrylate (PMMA) particles. We found three different segments for FOG deposits in the batch, namely static and buoyant micro-deposits, gel-like, and solid deposits. The average size of micro-deposits adhered to the solid-liquid interface of the container was 25 µm and buoyant deposits with a small size of 3 µm adsorbed onto the MPs at the liquid-air interface. The gel-like formation promoted a virtual liquid phase where PS and PMMA were confined and segregated. Some PMMA particles were entrapped in the self-assembly of biopolymers that formed between the PS particles. This research indicates that FOG deposition in the urban sewers contains high numbers of MPs, such that any plan involving a reuse or disposal program requires a risk assessment.

The salt obtained from salt sources has a low purity level and contains contaminants. The primary contaminants in the brines were eliminated in this investigation by using analytical separation (titration) techniques. Following the purification method, sodium hydroxide (NaOH) was added to magnesium chloride (MgCl2) to make magnesium hydroxide (Mg(OH)2) coagulate in pH control. This was done by PID and Self-Tuning PID (STPID) Control. Using STPID Control, hydrochloric acid (HCl) at a rate of 20% was employed as an effective acid current, MgCl2 as a coagulant, and NaOH at a rate of 10% as a neutralization base throughout the process. The coagulation technique was carried out with pH values of 7, 9, and 11, respectively. The pH of the medium was adjusted using the PID and STPID algorithms, as well as an on-line computer control system. As the system model, ARMAX was employed. As a forcing function, a pseudo-random binary sequence (PRBS) was used to identify the dynamics of the process to be controlled, and the system output was measured. The Bierman algorithm was used to evaluate the model parameters. The STPID controller's tuning parameters were calculated. Following the coagulation method, an analytical titration procedure was used to find out if there are any trace amounts of Mg(OH)2 in the current environment, and a settlement percentage of 90% to 95% was found. To get the best coagulation, a pH value of 11 was chosen as the optimal value based on the performed calculations.

The impact of atrazine and nitrate, the most used pesticide and fertilizer, on the health of Sclerophrys regularis was investigated in this study. We exposed the tadpole of Sclerophrys regularis to atrazine and nitrates to assess abnormalities and genotoxicity as biomarkers for environmental impacts. The proportional malformed toads were shown to be high when treated with nitrate alone (17%) or in combination (13%) or even treated with atrazine alone (the minimal, 5%), limbs and tail deformities are the most observed. Also, abnormal activity and movement were detected at all treated groups. In addition, Genotoxicity was measured by micronucleus test (MN) in detection of nuclear abnormalities in given species. The results indicate that individuals exposed to atrazine or nitrate or that exposed to both, exhibited a significantly higher degree (p < 0.01) of nuclear lesions. These results constitute key assessment of developing abnormalities and MN test in this species in Egypt and suggest that developing abnormalities and /or MN test and the degree of nuclear lesions of RBCs can be a useful indicator of the degree of environmental stress and ecosystem disrupting experienced by amphibian populations.

This study derives an analytical solution of a one-dimensional (1-D) Advection-Dispersion Equation (ADE) for solute transport with two contaminant sources incorporating the source term. Groundwater velocity is considered as a linear function of space while the dispersion as a nth power of velocity and analytical solutions are obtained for , and . The solution is derived using the Generalized Integral Transform Technique (GITT) with a new regular Sturm-Liouville Problem (SLP). Analytical solutions are compared with numerical solutions obtained in MATLAB pedpe solver and are found to be in good agreement. The obtained solutions are illustrated for linear combination of exponential input distribution and its particular cases. The dispersion coefficient and temporal variation of the source term on the solute distribution are demonstrated graphically for the set of input data based on similar data available in the literature. As an illustration, model predictions are used to estimate the time histories of the radiological doses of uranium at different distances from the sources boundary in order to understand the potential radiological impact on the general public for such problem.

The article presents the results of a study of heavy metals in snow and groundwater within the industrially developed Arkhangelsk agglomeration, which is the largest among urban formations in the Arctic zone of Russia. This article describes the results of research on the territories of three suburban community garden plots used by residents of the cities of the Arkhangelsk, Severodvinsk and Novodvinsk agglomeration for recreation, growing fruits and vegetables, picking wild berries and mushrooms, and short-term residence. In groundwater samples taken from wells, the average concentrations of heavy metals decrease in the following order: Fe > Mn > Zn > Cr > Ni > Cu > Ti > V > Pb > U > As > Co > Mo > Sb > Cd. A comparison of metal concentrations in groundwater with WHO and SanPiN standards showed that only Fe and Mn exceeded the permissible limits, for the rest of the studied metals, the concentrations were significantly below the permissible limits. The study of heavy metals in the snow showed a similar order of decrease in concentrations to groundwater and total concentrations of soluble metal fractions. This fact indicates the migration of heavy metals into groundwater after the spring snowmelt and the fact the main source of groundwater pollution is the atmospheric channel. According to the values of the total areal pollution of the snow cover with heavy metals, the most polluted are suburban garden plots in the area of the Arkhangelsk city – 216.91 mg/m2. The results of the principal component analysis showed that the main sources of snow cover pollution with heavy metals in the suburban areas of the Arkhangelsk agglomeration were thermal power plants, machine-building and metallurgical plants, a solid waste landfill, and vehicles. The calculation of the heavy metal pollution index for water did not reveal a significant anthropogenic impact. However, the indices assessing the amount of metals (heavy metal evaluation index), toxicity (heavy metal toxicity load), non-carcinogenic risk (hazard index), and carcinogenic risk indicate a high level of heavy metal pollution of the studied waters, as well as the unsuitability of groundwater and melted snow as drinking water. Metals such as Fe, Mn, Ni, Cu, and Pb make the greatest contribution to the quality indices of the studied waters.

The present study aims at determining the geotechnical properties of the tailings and the natural bed at Iran Mineral Processing Company, Sites 1 and 5. It qualitatively studies the subsurface layers of the company’s tailings storage site. After drilling different boreholes and conducting in-situ tests, it has made laboratory analyses in the form of field exploration to determine the geotechnical parameters of the extracted samples. Results from the analyses show the permeability coefficient of the subsurface layer of Site No. 1 and 5 to be very small, in the range of 10-7 cm/sec. Considering the conformity of permeability coefficient, percentage of fine grains (98% to 99%), plasticity index (28.5-29.5), and clay content of different layers of Sites 1 and 5 (68%-80%), based on the compacted clay liner criteria, it can be concluded that by nature, the subsurface layers of the mentioned sites are sealed with no need for any compacted clay liner. The tailings for storage Site 5 are fine-grained (80-88<75mm), basically in ML range according to USCS system, with a permeability coefficient of about 10-6 cm/sec. Therefore, the tailings themselves act as a relatively primary sealing layer against the infiltration of hazardous leachates into the natural bed. The method, used in the process of site selection of tailings storage facilities (TSF), can cut the construction time as well as the expenditures, thus reducing the production costs in the long run.

The present study evaluates the water quality of Dez River, a river 23 km long, via QUAL2Kw model, based on simulation of DO and BOD5 p98arameters, through considering water quality standards during six months in three stations of Kashefieh, Pole-Panjom, and Hamidabad. To determine the model’s validity and compare the observational data, the paper uses the square mean square error (RMES) and the squared mean square error coefficient (CV). The achieved results of the model largely indicate the actual conditions of the river, which represent the ability of QUAL2Kw model to simulate qualitative parameters. The main contamination of Dez River comes from municipal wastewater, either directly imported by river residents or collected by urban canals. It, then, enters the river at a certain point. Based on the simulation and observational results of DO at two stations of 5th and Hamidabad Bridge in all months of sampling, it is below 5 mg/L, regarded a threat to aquatic life. In addition, BOD5 parameter goes beyond 6 mg/L in Hamidabad station, being a threatening factor for aquatic life in this station. Critical conditions of Dez River, low discharge, and high loading of pollutants have increased the concentration of water quality parameters. Given the results of RMSE and CV parameters, the model has had the best conformity for DO parameter, followed by BOD5.