Journal of Applied Research in Water and Wastewater
Volume:8 Issue: 2, Summer- Autumn 2021

Surface water quality is of particular importance due to its drinking, industrial, and agricultural water sources. Changes in rainfall, temperature and river discharge can affect surface water quality. In this study, the effect of CANESM2, FIO, GFDL, MIROC climate models and weight composition model of CMIP5 (Coupled Model Intercomparison Project) under representative concentration pathways (RCP) of 4.5, 6, 8.5 scenarios on rainfall and temperature were investigated and then monthly discharge of the Aran river in Iran during 2020-2052 and 2053-2085 is predicted using the IHACRES runoff model. Next, the LSTM (Long Short-Term Memory network)-RNN (Recurrent Neural Networks) model were used to predict the total dissolved solids (TDS), sodium adsorption ratio (SAR) for the period 2020-2030. The results showed that the long-term monthly rainfall under the RCP8.5 scenario reported a further decrease compared to the RCP4.5 and RCP6, and the rainfall fluctuations were higher than the other two scenarios. Temperature changes in the second period are higher than the first period, so that in the first period under the scenarios of RCP4.5, RCP6 and RCP8.5 showed respectively 1, 1.5 and 2 degrees Celsius increase, while in the second period, 2, 3 and 4 degrees Celsius is predicted. The average discharge shows by 15.8 % and 20.97 % respectively decrease under the RCP4.5 scenario in the first and second periods, while by 8.51 % and 27.55 % under the RCP6 scenario and 6.38 % and 39.89 % under the RCP8.5 scenario compared to the observed discharge. The mean, maximum, and minimum TDS parameters under RCP4.5 scenario are, respectively, 295, 410, and 263, and 302, 410, and 257 under RCP6 scenario while 292, 410, and 257 mg, for RCP8.5 scenario. These changes are, respectively, 0.42, 0.93 and 0.14 for the SAR parameter in RCP4.5 scenario, and equal to 0.44, 0.94 and 0.1 in scenario 6, while 0.42, 0.93 and 0.15, respectively, for RCP8.5 scenario in Khorramrood river.

In this research, the performance of support vector machine in predicting relativeenergy dissipation in non-prismatic channel and rough bed with trapezoidalelements has been investigated. To achieve the objectives of the present study,136 series of laboratory data are analyzed under the same laboratory conditionsusing a support vector machine. The present study entered the support vectormachine network without dimension in two different scenarios with a height of 1.50and 3.0 cm rough elements. Two statistical criteria of Root Mean Square Error andcoefficient of determination are used to evaluate the efficiency of input compounds.Hydraulically, the results show that at both heights of the rough elements, energydissipation increased with increasing Froude number. The results of the supportvector machine show that the height of the roughness element is 1.50 cm in thefirst scenario, combination number 6 with R2 = 0.990 and RMSE = 0.0129 fortraining mode and R2 = 0.993 and RMSE = 0.032 for testing mode and the heightof the roughness element 3.0 in the second scenario, combination number 6 withR2 = 0.989 and RMSE = 0.0112 for training mode, R2 = 0.994 and RMSE = 0.0224for testing mode are select as the best models. Finally, sensitivity analysis isperformed on the parameters and H / y1 parameter is selected as the most effectiveparameter.

The use of a proper leak detection system in pipelines is of crucial importance in water transmission systems. In these methods, we should consider the time and accuracy of leak detecting procedure for preventing energy loss and reducing environmental impacts. In these days, seawater transmission lines are used for cooling systems, and for injecting water into the oil wells to improve oil recovery. Due to the more environmental impacts of saltwater, the leak detection system must have appropriate accuracy and speed in leak detection. The purpose of this paper is to choose a leak detection system for a saltwater transmission line. First of all, the specifications of different leak detection systems are provided. Finally, according to the mentioned project conditions, the most suitable method -fiber optic system- is recommended for these conditions. The most important advantages of this system are high accuracy, rapid leak detecting, and the ability of online monitoring of other parameters, such as temperature distribution or detecting intrusion into the buried line areas. These abilities result in improving safety and optimizing operating costs.

Water is one of the most important resources on earth. However, due to the drought crisis in Iran and the need to save water and study the determinants, this study was conducted to predict environmental behavior by relying on water consumption behavior based on environmental awareness, attitude, and concern. The research is a survey in which 865 citizens of Kermanshah City answered the research questionnaires by cluster sampling. The data was analyzed by statistical methods using SPSS software. The results showed that the variables of environmental knowledge (31 %), environmental concern (34 %), and environmental attitude (54 %) have the ability to predict the environmental behavior of water consumption. Therefore, people with higher knowledge, concerns and environmental attitudes are more diligent in saving water. According to the results of this study, explaining environmental behavior using three variables of environmental knowledge, environmental attitude, and environmental concern can be suggested to implementers and policymakers for use in developing interventions and educational campaigns and raising people's environmental awareness and knowledge. Also, these results can increase the paying attention to their environmental attitudes toward water consumption, can demonstrate that water conservation is realistic and practicable for people, and can convince them that they can engage in conservation-related behaviors. These results have the potential to raise people's awareness of their environmental attitudes about water consumption, illustrate that water conservation is feasible and achievable for them, and persuade them that they can engage in conservation-related actions.

The present study investigates the effect of treated wastewater and sludge on some vegetative characteristics of the Nitraria schoberi plant. This study was conducted in a randomized block template using several treatments include five levels of irrigation with wastewater (0, 25, 50, 75, and 100 %), two types of soil (arable land and desert soil of Meighan desert area), and two levels of sludge (presence and absence of sludge) with 6 repetitions for each treatment. SPSS software was used to perform the statistical analysis of plant morphological characteristics. The results showed that the highest increase in height, collar diameter, and the crown cover was observed when a wastewater level of 100 % was applied in the catchment basin soil of the Meighan desert at both presence and absence treatment of sludge. However, the same characteristics of Nitraria schoberi plant for cropland soils in the present treatment of sludge were at wastewater level of 100 % and in the absence treatment of sludge for plant height, collar diameter and crown cover diameter were at wastewater level of 50 %, 100 %, and 75 %, respectively. According to the results, different levels of wastewater have a significant impact on Nitraria schoberi plant height and crown cover diameter (P<0.01(. But different treatments did not show a significant difference in the collar diameter of the Nitraria schoberi plant. We can conclude that the use of wastewater should have a favorable effect on plants and soils of the desert area and should protect soil and water resources, but the environmental impact of treatments should be examined.

Although during the last two decades many studies have proved the effectiveness of the reverse osmosis system and this system has been used as a suitable and efficient method to treat drinking and industrial water and to desalinate the seawater, salt water, as well as sewage, it has some shortcomings, including sensitivity to ions, microorganisms, and organic matter in feed water causing problems such as scaling, fouling, as well as biofouling. Acidification of the permeate and its low pH are also other drawbacks of this system. This study is designed based on a two-pass reverse osmosis system, and each pass includes two stages (to provide higher system recovery). Moreover, ion exchange resin and AMBERPACK tank are used as pre-treatments considering the common problems of reverse osmosis system. Such fouling has been done to provide the required quality. It should be noted that by using the exchange resin system instead of the acid injection system, the TDS rate changed from 3.15 to 1.27 mg/L, which is equivalent to 59.68 % improvement, the LSI parameter, which in previous cases indicated severe fouling, ideally changed to -1.35 and -2.01. Also, the working pressure decreased from 13.7 bar to 12.5 bar, which indicates an 8.76 % improvement in working conditions.

Consumption and drinking of healthy and high-quality water is considered an important matter in human life, so monitoring of drinking water pollution including radioactive contamination and assessing the amount of radiation exposure of people through water consumption is very important. The purpose of this investigation was to measure the concentration of gross beta and alpha activities in water samples collected from Tehran water sources. In the present study, the gross beta and alpha activity concentrations of 35 water samples in Tehran were analyzed and measured to evaluate their radiological quality using liquid scintillation method. The results of the analysis showed the activity concentration of gross alpha ranges from 48 mBq/L to 227 mBq/L with a mean of 137.5 mBq/L. the activity concentration of gross beta in the samples ranged from 49 mBq/L to 328 mBq/L with a mean of 184.7 mBq/L. Also, the correlation coefficient between the results were very strong and equal to 0.87. The results showed that the gross beta and alpha activity concentrations in all waters was lower than the standard limit of the World Health Organization (WHO) and the Institute of Standards and Industrial Research of Iran, which is 500 mBq/L and 1000 mBq/L, respectively and also waters are radiologically healthy.

The objective of this work was to model and optimize the degradation of black azodye Naphthol Blue Black (NBB) by the Fenton process (advanced oxidation)using a minimum of experiments. A Plackett-Burman screening design was firstapplied to determine the main factors influencing the process. The dyediscoloration efficiency gave a yield approximately equal to 97 % in the bestconditions of several operating parameters used. The variance analysis (ANOVA)showed the effects of all different factors and deduced the most important ones.Subsequently, a second quadratic design of experiments central composite type(CCD) was applied using the response surface methodology (RSM) to optimizethe most important parameters deduced by the first design cited above, in order toobtain the best performance of the discoloration of NBB with this process. So from the contour plots and the response surfaces, the discoloration yield enhanced to the maximum and the optimization plot given by the Mnitab software, showed the following optimized parameters [NBB]=37.5 mg/L, [H2O2]=66.5 mg/L, [Iron]=3.5 mg/L and pH=3.4 for a yield of 100 % with a desirability of 1.0000. At last, to confirm that the discoloration was due to the degradation of the dye, the chemical oxygen demand (COD) was studied and in the optimized conditions, the degradation reached 94.78 % after 120 min of treatment. The kinetics of the dye degradation showed by the COD abatement was relatively slow compared to the kinetics of the dye discoloration.

This study evaluated the impact of heavy metal contents in vegetables grown in a palm oil mill effluents (POME) irrigated farmland on the biomes and well-being of humans that consume the vegetables. In this study, POME, a soil sample from POME irrigated farmland, and selected vegetables were evaluated. The results showed high cadmium (Cd), chromium (Cr), lead (Pb), nickel (Ni),) and arsenic (As) and lower zinc (Zn) and copper (Cu) concentrations in POME relative to their respective permissible limits. The soil irrigated with POME had elevated levels of metals, comparable to the control soil, whereas vegetable growing in POME irrigated farmland contained increased amounts of most of the heavy metals above their respective permissible levels in edible vegetables. The plant concentration factors (PCF) of heavy metals detected in the vegetables were less than one except for V. amygdalina with PCF>1 for cobalt. The pollution load index of Cd, Cr, Cu, Co, and As in the POME soil were above 50, while high enrichment factors were obtained for Cd, Cr, Pd, Co, and arsenic. The geoaccumulation index indicated that the POME soil was strongly contaminated by Zn, Fe, Pb, Mn, Ni and extremely contaminated with Cd, Cr, Zn, Cu, and Co. The metals levels ingested daily from the vegetables were low, comparable to their respective oral reference doses except for Mn in V. amygdalina and As in most of the vegetables. There was a high target hazard quotient for Mn, and As in most of the vegetables with hazard index (H.I.) >1 in each of the vegetables and increased cancer risk for Cd, Cr, Pb, Ni and As toxicity coupled with very high total cancer risks. These findings show that irrigation of farmlands with POME raises the heavy metal levels in vegetables and the risk of heavy metal toxicity.

In this study, the effect of antibiotic wastewater containing 20 common pharmaceuticals (14 antibiotics and 6 non-steroidal anti-inflammatory drugs (NSAIDs)) individually as well as their combination was investigated on activated sludge in batch reactors. The chemical oxygen demand (COD), the ammonium concentration, the inhibition rate and toxicity index of COD and ammonium were investigated in wastewater. The inhabitation for COD and ammonium removal was variable for each drug so that the pharmaceuticals are applied simultaneously had such a greater adverse effect on inhibition rate than individual compounds. The pretreatment of wastewaters containing drugs was performed by powdered activated carbon PAC to reduce the adverse effect of these drugs on activated sludge. The appropriate method for separation of PAC from wastewater before introducing to activated sludge process and the optimized adsorption and contact time during the pretreatment process were studied. The pretreatment of pharmaceuticals wastewater with activated carbon improved well COD and NH4 + removal to 71 % and 55 %, respectively, that demonstrate the activated carbon can be considered as a suitable pretreatment option for the activated sludge.

Herbicides such as 2, 4-dichlorophenoxyacetic acid (2, 4-D) are generally carcinogenic and their existence in water cause many problems. In this work, Fe3O4/FexCuyWzOt core/shell magnetic photocatalyst was used to remove 2, 4-D. The statistical analysis of the results of the Box-Behnken experimental design method revealed that among the constituents of the photocatalyst shell, iron had the highest effect on 2, 4-D photodegradation. The photocatalyst composition was optimized using the response surface method. The photocatalyst formulation was determined using ICP method Fe3O4/Fe0.874Cu0.349W0.004O1.525. XRD analysis confirmed the formation of Fe3O4, CuO, and WO3 in the photocatalyst shell. TEM images showed the photocatalyst core/shell structure. Fe3O4/Fe0.874Cu0.349W0.004O1.525 photodegraded 2, 4-D under ultraviolet light irradiation with the maximum yield of 90%. The photocatalyst was also active under sunlight and LED. The kinetics of the 2, 4-D photodegradation reaction under ultra violet light irradiation was studied. It followed first order kinetic model. The rate constant of the reaction was 0.0118 min-1 . The photocatalyst activity of Fe3O4/Fe0.874Cu0.349W0.004O1.525 remained constant after the fourth cycle of reuse, which is the good advantage.

The paper narrates a study of a numerical model taken into consideration to explore the overall hydraulic performance of Constructed wetland located at NUST H-12 Campus, Islamabad. The governing equations of flow in wetland ponds and the transport particle were solved using COMSOL Multiphysics 5.0. In this study, the simulation of the model is done to find the dead spaces and short-circuiting in the wetland along with providing remedial measures to reduce the dead spaces. The comparison of two turbulent models i.e. K-ω and K-ε were also made to depict the velocity of wetland and the particle tracer study was also conducted to find the behavior of wetland. The model was simulated with experimental data and the results revealed that 15% to 20% area of wetland is experiencing short-circuiting. Alternative wetland designs were suggested for the same flow condition. The K-ω model was considered to be more suitable due to the limitation of K-ε model.