JOURNAL OF ENVIRONMENTAL HEALTH ENGINERING
Year:2018 | Volume:5 | Issue:2 |Papers Count:8

Background: Diazinon is one of the most important pesticides extremely used in agriculture. Since these compounds are resistant to biodegradation, the arrival of these compounds to water resources has become a serious environmental problem. Therefore, in the current work, the removal of diazinon from groundwater was investigated using advanced oxidation processes electro Fenton.Methods: the current work was conducted in lab scale. The effect of operating parameters such as initial concentration of diazinon (1-30 mg.L-1), pH solution (3-9), current density (1-10 mA.cm-2), reaction time (3-30 min), and dosage of H2O2 (20-100 mL.L-1) were investigated. Response surface methodology (RSM) was used to optimize the parameters and suggested model was analyzed using ANOVA.Results: On the optimum condition including initial diazinon concentration of 6.88 mg.L-1, pH solution of 3, the reaction time of 10 min, the current density of 8.18 mA.cm-2, and dosage H2O2 of 83.78 mL.L-1 removal efficiency of diazinon was found to be 98.5 %. Electrical energy consumption (EEC) was found to be 0.524 kWh.m-3. Moreover, the concentration of diazinon in groundwater was found to be 0.934±0.053 mg.L-1.Conclusion: According to the obtained results, electro Fenton process was found to be an efficient technique for successful removal of diazinon and other resistant ungradable organic compound from water sources.

Background: As for the enhancement of the various industries such as loom industry, the reduction of the pollutants in the sewerage of these industries is focused by protection office of environment.Therefore, the main aim of this research is the elimination of the methyl orange from water using photocatalytic procedure and ZnO nanoparticles.Methods: The kinetic of the photocatalytic oxidation reaction of methyl orange using ZnO nanoparticles and hybrids containing decorated Multi Wall Carbon Nanotubes (MWCNT) with ZnO nanoparticles is investigated. The influence of irradiation time (from 5 to 30 min) and the concentration of the photo catalysts (0.1, 0.2 and 0.5 %wt) on the kinetic reaction of methyl orange decomposition is studied.Results: The kinetic reaction of methyl orange decomposition using ZnO nanoparticles and synthesized hybrids is pseudo first order. The reaction rate constant using ZnO nanoparticles is lower than that of studied hybrids. This means that the reaction rate of methyl orange decomposition using ZnO nanoparticles is low. Meanwhile, according to the results it can observe that the attachment of the ZnO nanoparticleson the outer surface of MWCNTs leads to the enhancement of the reaction rate. Also, the reaction rate of pollutants decomposition increases with respect to the attached ZnO nanoparticles on the outer surface of MWCNTs.Conclusion: Based on the observed results, the introducing and enhancement of the ZnO nanoparticles on the outer surface of MWCNTs leads to the augmentation of the methyl orange decomposition rate. Therefore, according to this technique the decomposition of the pollutants accelerates.

Background: Due to their polycyclic and toxic structure, dyes have a high ability in causing adverse acute and chronic effects on human exposed to them. In present study, the decolorization of acid green3 from aqueous solution by UV/ H2O2 method was investigated Methods: This is an applied-experimental study. Parameters of pH in the amount of 3, 7 and 11, contact time in 5, 15, 30, 45 and 60 min, dose of H2O2 in 10, 30 and 50 mg/l and initial concentration of acid green3 in 50, 100 and 150 mg/l were examined to reveal the optimum amounts of these parameters. In order to emit the UV radiation, photo reactor with a 2-lit volume was applied, also to measure remaining concentration of dye, spectrophotometer device, model DR 5000 was employed.Chemical oxygen demand (COD) test based on 5220C method (standard method book) was used for determining amount of oxidation.Results: Results showed that contact time=60 min, pH=7, acid green concentration=50 mg/l and dose of H2O2=30 mg/l are optimum condition at which the removal amounts of dye and COD were obtained about 97 and 85%, respectively.Conclusion: In the study, it is observed that parameters of contact time, pH, initial concentration of dye, and dose of H2O2 have a significant influence on the removal of the dye by UV/H2O2 process.Due to acceptable results of UV/H2O2 in the oxidation of the dye and the reduction of COD, this method can be introduced as reliable process to remove of acid green 3 from industrial wastewaters.

Background: Antibiotics to treat an illness or as a growth promoter, to be consumed. A pharmaceutical composition in the form of original or metabolized in the aquatic environment, due to increased bacterial resistance is a concern. Various methods have been used to remove it. The advanced oxidation process due to the ease of use, economical and high performance have attracted a lot of attention. The purpose of this study was to investigate the role of cerium dioxide on process efficiency combined UV/AC+ZnO as an advanced oxidation process is the removal of cefazolin in the aquatic environment.Methods: This experimental study was done in batch reactor that has a one Liter volume. In this study effect of parameters such as initial pH (3-9), initial concentration of Cefazolin (20-200 mg/L), Modified photocatalyst concentration (20-100 mg/L), reaction time (10-60 min) and CeO2 dose (20-200 mg/L) was investigated. In this study use of low-pressure mercury lamp with a power of 55 watts in stainless case. The kinetic of process according to zero order, first order and second order kinetic was evaluated.Results: The results showed that the highest removal efficiency of antibiotics cefazolin in the process at the pH=3, concentration 0.1 mg/L of Modified photocatalyst, Retention time of 60 min and Cefazolin concentrations of 100 mg/L was 96%. When you change any of the parameters of about optimization, process efficiency was renamed. The results also showed that by increasing the concentration of CeO2, the antibiotic removal efficiency decreased, so that by increasing the concentration of CeO2 from 20 to 200 mg/L, the antibiotic removal efficiency of cefazolin decreased from 91 to 76%.Conclusion: This process has shown high efficiency in removal cefazolin and the ability of this process to reduce the burden on hospital sewage and pollution-producing industries before entering the units and final discharge effluent also contains conventional treatment or used for cefazolin. This process, because of the lack of production waste such as sludge, a process persistent organic pollutants and significant in the treatment process is environmentally friendly.

Background and objective: Regards to the importance of using safe vegetables, controlling the concentrations of heavy metals is necessary for consumer's health. Therefore, this study was aimed to evaluate the effect of sugarcane bagasse biochar and municipal waste vermi-compost on the changes in cadmium risk assessment from tomato consumption.Methods: Treatments were consisting of applying municipal waste vermi- compost (0, 5and 10 t ha-1) enriched with 0 and 5% (W/W) sugarcane bagasse biochar in a polluted soil (0, 10, 20 and 30 mg Cd kg-1 soil) and plant in this experiment was Tomato. Cd fruit concentration was measured by AAS. Risk assessment to non-cancer diseases was estimated using USEPA formula.Results: Applying 10 t ha-1 municipal waste vermi-compost in a 30 mg Cd polluted soil caused a significant decreasing in Cd fruit tomato by 25%, While, daily Cd absorption from tomato consumption and Cd dangerous Potential to noncancerous diseases was also decreased by 27 and 22 %, respectively Conclusions: The results of this study showed that applying Lenjan municipal waste vermi-compost and sugarcane bagasse biochar caused decreasing Cd availability in soil and Cd absorption from tomato consumption that is a positive point in reduction Cd dangerous Potential to noncancerous diseases.

Background: Pollution of aquatic ecosystems to heavy metals is one of the most important threats of human health and its food chain. Thus, in this study the concentration of heavy metals (lead, chromium, copper, and zinc) in Surface sediments andNasturtium microphyllum was investigated in order to assessment their effects and ecological risk.Methods: In order to assess the concentration of metals, 8 stations along the river were selected and in each station two samples of sediment and plant were taken. After preparinng and digesting the samples, the concentrations of these metals were determined using Atomic absorbtion.Results: The average of total concentration of detected metals Cr, Pb, Cu and Zn in sediment (10.33 ± 0.02>13.35±1.10>33.07 ±6.13>44.02 ± 4.13) mg/kg respectively. In addition, evaluation indicators such as; Pollution Load Index (PLI) and ecological risk represents less pollution in the region. Also, the environmental risk of metals in the region was evaluated as (Cu>Pb>Zn>Cr). The results of concentration of metals in different organs of root, stem and leaf ofNasturtium microphyllum showed that the highest average accumulated concentration for each metal was obtained in stem, root and leaf, respectively.Conclusion: According to the results, the pollution and ecological risk of metals in the region is low evaluated. The results of this study confirm the use ofNasturtium microphyllum as a heavy metals accumulation species and a suitable indicator for their biomonitoring.

Background and Objectives: Conventional wastewater treatment plants are not able to remove effective drugs, such as antibiotics, so eliminating remaining antibiotics from the environment is important. The purpose of this study was to evaluate the efficacy of UV / ZnO photocatalytic process in removing antibiotic cephalexin from aqueous solutions.Materials and Methods: This is an experimental-applied study that was performed on a batch scale in a laboratory scale. The variables studied in this study included the initial pH of the solution (11, 9, 7, 5, 3), the dose of nanoparticles (1, 75.0, 0.5, 0.25, 0.1, 0.05 grams per liter), Reaction time (60-50-40-30-20-15-55 minutes) and initial concentration of pollutant (100, 50, 25, 10 mg / l) were investigated. Measurement of cephalexin in samples was performed using HPLC apparatus.Results: The results showed that by decreasing pH and reducing the initial concentration of cephalexin and increasing contact time, process efficiency increased. But with increasing nanoparticle dosages up to 0.1 grams per liter, the process efficiency increases and more than this amount is reduced.Conclusion: The results of this study showed that the use of UV / ZnO photocatalytic process in removing humic acid from aqueous solutions can be used as an effective method for cephalexin from aqueous solutions.

Background and Aim: High concentrations of antibiotics are now detected in aquatic environments, reducing their quality. These compounds generally have a high toxicity and low biodegradability, and some are reported to have mutagenic and/or carcinogenic characteristics. Conventional treatment systems have proven inadequate to effectively remove this type of organic compound, largely due to its complex molecular structure. Therefore, it is necessary to remove an effective method for the removal of these compounds is suggested. The purpose of this study was to apply zero-valent iron nanoparticles in the presence of hydrogen peroxide and the process of sonolysis in the removal of antibiotic amoxicillin from aquatic environments.Materials and Methods: This research was carried out on a laboratory scale on a synthetic wastewater containing amoxicillin antibiotic that the effects of some parameters, such as ultrasound (35 and 130 kHz), contact time (30–150 min), concentration of hydrogen peroxide (0.5–3 %), concentrations of nZVI (0.06–0.2 g/L), pH (3–10), and concentration of AMX (45–100 mg/L) were investigated.Results: Optimum removal conditions were pH=3, H2O2 concentration=1%, ultrasonic frequency=130 kHz and nZVI concentration=0.2 g/L. so that 97.3% of amoxicillin antibiotic after 150 min of reaction at pH=3, nZVI=0.1 g/L, ultrasonic frequency=130 kH, H2O2=1% and 45 mg/L concentration of AMX was removed.Conclusion: The experiments showed the efficient removal of amoxicillin antibiotic in wastewater by Fenton’s oxidation process. The efficiency of this method can also be considered in eliminating other antibiotics resistant to biological treatment.