Objectives:To compare water quality parameters in the vicinity of Gas Flaring Area of Ebocha-Obrikom of Rivers State with that of the recommended standards.Methods:The research utilized standard analytical procedures. All sampling, conservation, transportation and analysis followed standard procedures described in APHA (2012). All the samples collected were transported to the laboratory through keeping in an icebox to prevent degradation of the organic substances.Results:Result depicts that Turbidity, DO, BOD, COD, TSS, Magnesium, Iron, Cadmium, Lead, Chromium, and Nickel exceeded the desirable limit meant for drinking purpose as well as could potentially pose threats toward human society. Hence, remain unsuitable for drinking, as the inhabitants were more vulnerable for their total lifetime period of exposure through continuous consumption of unsuitable drinking water.Conclusion:It is recommended that the local government environmental health officers and other regulatory agencies frequently monitor the levels of these pollutants within the area and also ensure strict adherence to guidelines to ensure a healthy environment. As exposure to the above stated parameters can have a remarkable impact on human health living in the vicinity of the gas flaring area by drinking water around the study area; thus, groundwater needs to treated before using for household purpose or drinking. Thus, this study would help in decision making for stakeholders and relevant authorities in the execution of reasonable groundwater management strategies and remediation plans in the area to protect public and environmental health.

Preparation of an efficient hybrid structure photocatalyst for photocatalytic decomposition has been considered a great option to develop renewable technologies for environmental remediation. Herein, ternary magnetic Fe3O4/GQD/g-C3N4 nanocomposite (FGC) was prepared using the ball mill method. Binary nanocomposites Fe3O4/g-C3N4 (F/CN) and GQD/g-C3N4 (G/CN) were prepared to compare photocatalytic activity with FGC. The performance of photocatalysts for degradation of rhodamine B (RhB) was studied. EDX results showed that Fe3O4, GQD and g-C3N4 nanoparticles (NPs) are uniformly distributed in the FGC. The FGC nanocomposite shows superparamagnetic behaviour with a saturation magnetization of 12 emu. g-1, which makes it favourable compound for magnetic separation procedure. Photocatalytic activity of FGC (100%) was much higher than those of the G/CN (88%) and F/CN (77%) photocatalysts. The superior activity of FGC compared to binary composites was attributed to broader absorption in the visible light band and greater suppression of electron-hole recombination. The photocatalytic degradation of RhB using FGC was consistent with pseudo-first-order kinetics. The reusability of FGC was examined for four runs and no noticeable decrease was observed with the same irradiation time for each run. Finally, it can be argued that FGC photocatalyst can be an efficient semiconductor for the degradation of organic dyes from wastewater.

Events such as the emission of toxic gases are possible on floating roof storage tanks. Since gasoline is a high-consumption and volatile product stored in adjacent oil depots or large cities, it is necessary to assess their emission risk. Given that the multi-criteria methods allow the identification of and assessment of the indicators well and allow the participation of expert experts, so the FAHP method has been used to identify and assess the risk before the emission of toxic gases. The results showed the importance of 7 factors among 36 factors, 3 of which were related to equipment error. The DOW'S CEI method was used to assess the emission risk if the event occurred. This method provides safe boundaries based on Emergency Response Planning Guidelines (ERPGs), where the results indicate the settlement placement around the oil repository in the range of the predicted concentration at all three levels of ERPG.

In order to evaluate the impact on water quality of the abandoned Sidi Kamber mine in Skikda, NE Algeria, Pb, Zn, Cd, Fe, Cu, Mn and Ni metals were collected at surface water and groundwater, from twenty eight sites located near the mine. Conventional hydrochemical methods, heavy metal pollution index (HPI) and multivariate statistical analysis techniques: correlation matrix (CM), principal component analysis (PCA) and hierarchical cluster analysis (HCA) were used. Surface water results show that El-Souk River has a high level of pollution, but Guenitra dam water is less contaminated. Regarding the groundwater results, the wells and springs are not suitable for drinking. The overall quality estimated by HPI values of surface and groundwater are poor; they may pose a potential health risk to the local population. The PCA and HCA suggest that surface water and groundwater are contaminated by two sources: anthropogenic and natural. According to the obtained results, surface water and groundwater pollution state of this area raises serious concerns about health and environment.

Solar disinfection is becoming increasingly popular around the world for eliminating pathogens present in wastewater. The goals of this study were to identify the significant variables and to maximize the log reduction values (LRV) of total coliforms present in treated urban wastewater using solar disinfection. To achieve the goals, a 23 full factorial design of experiments and response surface methodology were used. Solar disinfection was carried out in an open-air batch reactor and in a solar batch reactor. The three variables considered were solar irradiation, volume of sample and exposure time at two markedly different levels: solar irradiation (1100 Wh/m2 and 1700 Wh/m2), volume of sample (0.2 L and 2L), and exposure time (0.5 h and 3 h). When compared to other variables, exposure time was the most significant factor in the analysis of variance (ANOVA) study for both the reactor conditions. The regression equation developed for a solar reactor does not adequately explain the variability of the experimental data when compared to the regression equation developed for an open-air reactor. According to the response optimizer, the optimum values of the factors for solar disinfection using a solar reactor to achieve an LRV of 2 for 0.25 L of sample volume are 1700 Wh/m2 solar irradiation and 2.97 hours of exposure time. With an open-air reactor, 0.2 L of sample must be exposed to 1700 Wh/m2 of solar irradiation for 3 hours to achieve LRV of 2.

Melanoidin is the hazardous dark brown byproduct generated during palm oil extraction in the crude palm oil industry. In this study, the laccase-producing consortium W3 (Bacillus licheniformis and Bacillus subtilis) was used to degrade melanoidin and decolorize palm oil mill effluent (POME). The microbial fuel cell (MFC) has been applied for enhancing decolorization and generation of electrical energy as a byproduct. The results displayed the maximal melanoidin removal of 95.20±0.10% was gained when the consortium W3 was added into the synthetic wastewater. While the maximal decolorization of 75.10±0.12% and 73.91±0.23% were gained from the sterile POME and raw POME respectively without chemical addition. Moreover, the power output of 2.13±0.05 W/m3 or 0.27±0.01 W/m2 was achieved from the POME-fed MFC with W3. This study gained new knowledge of using the laccase-producing bacterial consortium integrated with MFC for melanoidin removal from the POME and generation of electrical power as an alternative energy source.

This work investigates the possibility of using constructed wetland system for the management of municipal wastewaters with reuse strategies for the irrigation of landscapes in Ouled Djellal city of Biskra, Algeria. The design of this system was based on the characteristics (volume and physico-chemical properties) of wastewaters and the urban plan of the studied city. Results showed that studied effluent is easily biodegradable with COD/BOD5 of  1.84 (< 3), BOD5 (325 - 365 mg/L), COD (620-644 mg/L) and TSS (120-250mg/l). The peak of raw wastewater flow was found to be 32.4 m3 /h, which was used for the calculation of drip network for the landscape irrigation. The selected variant for the configuration of the CW system is HF-VF-HF, which occupies an area of 11.580 m2 and will reduce significantly the water pollution. The treated wastewater will be reused for the irrigation of landscapes via the dimensioned drip network. Results of this study showed that the proposed design for the system (treatment and reuse) would be effective in reducing pollution in the urban environment by ensuring possibility of the reuse of the treated water for irrigation. This gives also a great opportunity for using this strategy in small neighborhoods in other cities.

In developing countries, wastewater treatment is confined to secondary systems. Hence even after treatment, wastewater effluent has a high level of nutrients which causes eutrophication and has destructive impacts on receiving bodies. Literature reveals that phycoremediation can be the best solution to address the problem faced but is time-consuming, ranging from days to weeks. Hence, the present study aimed to determine an optimum detention time for the microalgal system to treat domestic wastewater. The retention time for treatment in the study was divided into an aeration and settling periods. During the study, aeration time varied from 2 hours to 24 hours, followed by 1-hour settling period for each aeration time. Optimum detention time for microalgal treatment was obtained at 11 hours of detention time (10 hours aeration and 1-hour settling). Parameters analyzed during the study were pH, EC, TS, TSS, TDS, nitrate, phosphate, ammonia, COD and DO. However, the main focus was on nutrients (phosphate and ammonia) and organics (COD) removal while determining the optimum detention time. Maximum removal efficiency obtained for COD, ammonia and phosphate for non-filtered effluent was 75.61%, 90.63% and 83.29%, respectively. However, removal efficiency further increased for filtered effluents to 86.34%, 100% and 91.12% for COD, ammonia and phosphate, respectively. Algal treatment offers an ecologically safe and more affordable system for nutrient removal and eliminates the need for tertiary treatment.

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.

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.