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Convenient and Efficient Elimination of Heavy Metals from Wastewater Using Smart Pouch with Biomaterial
2019
Malik, R. | Saini, N. | Ahlawat, S. | Singhal, S. | Lata, S.
A newly developed Smart Pouch with enclosed biomaterial (Aloe vera and coconut husk powder) has been experimented for elimination of heavy metals i.e. (Pb2+, Cu2+, Ni2+ and Zn2+) from wastewater. The effect of concentration, pH, temperature, contact duration etc. was investigated using batch experiments which resulted that the Pouch may be accepted for convenient, efficient and low-cost accumulation of several heavy metals simultaneously from waste water. The maximum Pb removal was 99.99%, 93.21% for Cu, and for Ni, it was 91.97% whereas for Zn, 86.41% was obtained and also, the uptake capacity of pouch was quite sensitive towards initial metal concentration in the studied range of 10-200mg/L present in wastewater. The findings were further interpreted by quantum chemical study as theoretical support, various adsorption isotherms, FTIR, SEM, XRD, and physiochemical properties of metal ions to justify the synergized performance of new Pouch. A good correlation was found between experimental methods and theoretical findings.
Afficher plus [+] Moins [-]Study of seasonal and spatial variability among Benzene, Toluene, and p-Xylene (BTp-X) in ambient air of Delhi, India
2019
Garg, A. | Gupta, N.C. | Tyagi, S.K.
This study was carried out to analyze the variations of Benzene, Toluene, and para- Xylene (BTp-X) present in the urban air of Delhi. These pollutants can enter into the human body through various pathways like inhalation, oral and dermal exposure posing adverse effects on human health. Keeping in view of the above facts, six different locations of Delhi were selected for the study during summer and winter seasons (2016-2017). The concentrations of BTp-X on online continuous monitoring system were analyzed by chromatographic separation in the gaseous phase followed by their detection using a Photo Ionization Detector (PID). The concentrations of BTp-X were found maximum at a high traffic intersection area as 68.35±48.26 µg/m3 and 86.84±32.55 µg/m3 in summer and winter seasons respectively and minimum at a residential area as 4.34±2.48 µg/m3 and 15.42±9.8 µg/m3 in summer and winter seasons respectively. The average BTp-X concentrations of summer and winter seasons were found as 9.88, 20.68, 28.52, 49.75, 64.04, and 77.59 µg/m3 at residential, institutional, commercial, low traffic intersection, moderate traffic intersection and high traffic intersection areas respectively. Clearly, it has been found that the concentrations of these compounds were more on the traffic areas indicating that the vehicles are the major emission source. Hence, it may be concluded that the number of vehicles along with the high traffic congestion on the city streets and roads results in more accumulation of aromatic compounds and deteriorate the urban air quality.
Afficher plus [+] Moins [-]Influence of Copper Oxide Nanoparticle on Hematology and Plasma Biochemistry of Caspian Trout (Salmo trutta caspius), Following Acute and Chronic Exposure
2019
Kaviani, E. F. | Naeemi, A. S. | Salehzadeh, A.
The Caspian trout is an endangered and quite vulnerable fish, considered for a natural protection program in the southern area of the Caspian Sea. Copper oxide nanoparticles (CuO-NPs) are toxic substances, which induce oxidative stress, not to mention other pathophysiological states. The toxicity of nanoparticles on fish needs more characterization for short- and long-term effects. Thus, the present paper examines the acute and chronic effects of CuO-NPs on hematology and plasma biochemistry of juvenile Caspian trout. After determining the lethal concentrations (LC50), juvenile Caspian trout is exposed to 0.1 LC5096 CuO-NPs for 28 days in three replicates. The blood samples are then collected from fish after 24, 48, 72, and 96 hours as well as 1, 2, 3, and 4 weeks of exposure to the CuO-NPsto deal with short- and long-term effects, respectively. Analysis of these samples shows that some hematological factors like hemoglobin (Hb), red blood cells (RBC), and hematocrit (Hct) are significantly increased after acute exposure, compared to the control group (p<0.05). The number of white blood cells (WBC), neutrophilis, and monocytes are also increased after acute and chronic exposure with significant differences (p< 0.05). Furthermore, the levels of lactate dehydrogenase after acute and alkaline phosphatase along with aspartate aminotransferase after acute and chronic exposure are significantly increased (p<0.05). Thus, results indicate that the presence of even a tiny amount of CuO-NPs can affect most haematological and metabolic enzymes of the Caspian trout in the short and long-term exposure. It is therefore essential to prevent these nanomaterials from entering the aquatic environment.
Afficher plus [+] Moins [-]Verification of IVE Model for SAIPA Co. Fleet Emission
2019
Alipourmohajer, Sh. | Rashidi, Y. | Atabi, F.
To determine the amount of air pollutants, produced by Iranian automakers, and compare it with old and retrofitted vehicles have become one of the important tools of urban management. The present research uses International Vehicle Emission (IVE) modeling software in order to verify SAIPA Co. fleet emissions, based on Euro 4 emission standard (SAIPA Co. recognized as a superior Iranian brand in vehicle industry). There has been attempts to determine pollutant emission from Saipa Co.-manufactured cars in the city of Tehran, in accordance with Tehran Driving Cycle along with modeling and lab results which have over 90% conformity with modeling and lab results of New European Driving Cycle. According to ISQI’s 100,000-km test results, the amount of CO2 emission modeling from X100 and Tiba2’s has been about 160 gr/km, which has been within the range, whereas the modeled CO2 emission rate has been 232 gr/km in TDC, i.e., 1.5 times more than laboratory test, due to different driving cycle usage. Significant differences between the values obtained in the emission lab and modeling at New European Driving Cycle, Tehran Driving Cycle, and Tehran Air Quality Control Company report, indicate that relying on hypothetical situation leads to inapplicable emissions value from light vehicles.
Afficher plus [+] Moins [-]Monitoring of SO2 column concentration over Iran using satellite-based observations during 2005-2016
2019
Salmabadi, H. | Saeedi, M.
For the first time, sulfur dioxide concentration was monitored between 2005 and 2016 over Iran which is among the countries with a high SO2 emission rate in the world. To that end, SO2 column concentration at Planetary Boundary Layer (PBL) from Ozone Monitoring Instrument (OMI) was analyzed. OMI is a sensor onboard the Aura satellite which can measure daily SO2 concentration on the global scale. From OMI maps, 19 notable SO2 hotspots were detected over Iran. The results indicate that the most elevated level of SO2 among these 19 hotspots belong to Khark Island and Asaluye in Bushehr province, southwest of Iran. Annual trend analysis shows that SO2 concentration has been slightly augmented during 2005-2016 over this country. Distribution analysis of SO2 concentration over Iran showed that the most polluted provinces are Bushehr, Khuzestan and Ilam lied in the southwest of Iran. On the contrary, the lowest level of SO2 has observed over northwest of Iran at West and East Azerbaijan and Ardabil provinces. The correlation coefficient between total energy production in Iran and SO2 concentration from 2005 to 2016 is as high as ~0.7. Hence, it can be derived that energy production, most notably production of crude oil, plays a pivotal role in SO2 concentration over Iran.
Afficher plus [+] Moins [-]Degradation of Hydrocarbons and Lignin-like compounds by Alcaligenes sp. strain 3k isolated from Ilorin
2019
Adetitun, D. O. | Fathepure, B. | Hugh, H. | Kolawole, O. M. | Olayemi, A. B.
The primary goal of this study was to isolate hydrocarbon-degrading organisms and assess their ability to bioremediate petroleum-contaminated soil and water. Nigeria is one of the major oil producing countries and petroleum contamination is widespread in agricultural soil. Alcaligenes sp. strain 3k was isolated from a kerosene-polluted soil in Ilorin, Nigeria. We also assessed its ability to degrade plant lignin, as lignin is a complex aromatic heteropolymer commonly found in soil and aquifer environment. Strain 3k was originally grown on mineral salts medium with kerosene as a sole energy and carbon source. The capacity of the isolate to degrade both aromatic, aliphatic hydrocarbons and lignin-like compounds was tested. Among the tested compounds, the organism utilized kerosene, hexadecane, cyclohexane, phenol and benzoate as the sole sources of carbon. In addition, strain 3k also degraded various lignocellulose compounds as the sole source of carbon. However, hexane, benzene, toluene, ethylbenzene and xylene were not metabolized. Our study demonstrates that soil organisms like Alcaligenes could play important role in the reclamation of petroleum-contaminated soil and water. Utilization capacity of lignin as the sole carbon source suggest that these organisms can survive on plant detritus and also have the ability to degrade hydrocarbons upon accidental or deliberate contamination of agricultural soil and water.
Afficher plus [+] Moins [-]The Evaluation of Tropospheric Ozone Formation in the Downwind of the South Pars Industrial Zone
2019
Moradzadeh, M. | Ashrafi, k. | Shafiepour-Motlagh, M.
Hydrocarbon Processing Industries (HPIs) emit large amounts of highly reactive hydrocarbons and Nitrogen Oxides to the atmosphere. Such simultaneous emissions of ozone precursors result in rapid and high yields ozone (O3) formation downwind. The climate of the Middle East has been shown to be favorable for O3 formation in summer. There are also vast activities in processing oil and gas in this region. This study aimed to investigate the influence of HPIs located in the Middle East on ozone formation. We chose the South Pars Zone (SPZ) located in the coastal area of the Persian Gulf with concentrated HPIs as a case study. To do this, after developing an emission inventory for O3 precursors, we used OZIPR, a Lagrangian photochemical model, coupled with SAPRC-07 chemical mechanism to describe the effects of HIPs on ozone formation in the SPZ and downwind area from June to August of (2017). Results indicate that the SPZ has a far-reaching and wide-ranging impact on O3 formation in downwind areas and an area at a distance of 300 km can be affected profoundly (Average 0.06 ppm and maximum increase 0.24 ppm). Given the large numbers of HPIs located in the Middle East, we predict that the transport of O3 and its precursors from this region play an important role in the ozone air pollution in a much wider area and the role of these industries should be taken into account for regional and interregional ozone concentration modeling.
Afficher plus [+] Moins [-]Radiological dose Assessment by Means of a Coupled WRF-HYSPLIT Model under Normal Operation of Bushehr Nuclear Power Plant
2019
Feyzinejad, M. | Malakooti, H. | Sadrinasab, M. | Ghader, S.
In the present work WRF model is used to generate meteorological fields for the HYSPLIT dispersion model. Sensitivity and validation of the WRF model, is conducted by utilizing different combinations of physical parameterization schemes. For this purpose, eight different configurations are examined. Assessment of the predictions of the WRF model is carried out by computing the statistical parameters including correlation coefficient (CC) and root mean square error (RMSE). As an example of the results of the WRF model utilizing proper physical configuration at Bousher syoptic station at 03/01/2005 leads to CC=0.82007 and RMSE=1.91783 for wind speed parameter. Once the proper configuration of the WRF model is obtained, dispersion simulations and annual effective dose for adult age group are carried out by WRF-HYSPLIT coupled model under normal conditions for Bushehr power plant. Simulated annual effective dose for adult age group by the coupled model for the years 2014, 2015 and 2016 are 5.8E-08 Sv/yr, 6.7E-08 Sv/yr and 1.1E-07 Sv/yr respectively. Results show that simulation and prediction of effective dose with coupled WRF-HYSPLIT model are in good agreement with observations and indicates the validity of the simulations. The ratio of predicted annual effective dose to dose limit (1E-04 Sv/yr) for normal operation is obtained less than 0.2 percent (
Afficher plus [+] Moins [-]Improvement of Anaerobic Digestion of Sewage Sludge, Using Combined Hydrogen Peroxide and Thermal Pre-Treatment
2019
Hallaji, S. M. | Siami, S. | Aminzadeh, B.
The present study investigates the influence of individual and combined hydrogen peroxide and thermal pre-treatment of waste activated sludge on anaerobic digestion. For so doing, it employs anaerobic batch reactors in the mesophilic conditions. For comparison, soluble fractions of organic matter, biogas production, biochemical methane potential, removal of chemical oxygen demand (COD), and volatile solids (VS) have been measured during the anaerobic digestion process in systems with and without pre-treatment. Hydrogen peroxide pre-treatment has been tested in two concentrations of 30 g H2O2/kg VS and 60 g H2O2/kg VS and thermal pre-treatment has been performed at two temperatures of 75℃ and 90℃. According to the results, the solubalisation of organic matter considerably improves, when combined hydrogen peroxide and thermal pre-treatment is employed. As a result, in comparison to the control reactor, higher amounts of biogas (71%) and methane (81%) have been produced in the bioreactor, pre-treated with combined hydrogen peroxide (30 g H2O2/kg VS) and heat (90 ℃). In addition, the removal efficiency of COD and VS from the digested sludge has been enhanced in the pre-treated reactors (up to 39% and 92%, respectively) in comparison to the control reactor. The improved methane yield, COD, and VS are of paramount importance, not only because higher amounts of renewable energy are obtained from the anaerobic digestion process, but because sludge transport costs are reduced and the digested sludge obtains a higher potential application to agricultural lands.
Afficher plus [+] Moins [-]Study of Cadmium and Nickel Removal from Battery Industry Wastewater by Fe2O3 Nanoparticles
2019
Shahriari, T. | Mehrdadi, N. | Tahmasebi, M.
Nickel and cadmium usually enter the environment and water resources through wastewater, released by various industries, and may have adverse effects. The current study employs α–Fe2O3 nanoparticles of 20-40 nm in order to remove nickel and cadmium from the wastewater of Saba Battery Company. Also, it investigates the influence of effective parameters on adsorption process, including pH, contact time, and the adsorbent rate so that it can optimize the adsorption process. The maximum adsorption rate of nickel and cadmium can be observed in pH ranges of 5 to 9. In addition, adsorption rates for nickel (at pH = 7) and for cadmium (at pH = 5) have been 92.98% and 93.97%, respectively. By increasing the adsorbent rate, the adsorption grows, due to the increase in absorbate surface area, and an optimum adsorbent rates of 0.15 g and 0.2 g are obtained for cadmium and nickel, respectively. The maximum nickel and cadmium adsorption rates occur during the first 60 min of contact with nanoparticles. In this study, adsorption kinetics and isotherms have also been investigated and it has been found that the adsorption kinetics of both nickel and cadmium ions follow the pseudo-second-order model, while adsorption isotherms of nickel and cadmium follow the Freundlich model.
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