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Investigation of Heavy Metal Traces during Drilling Operations in the Bibi Hakimeh Oil Field, Iran
2021
Baikpour, Shahram | Noorani, Mohammad Javad
Drilling operations release considerable amounts of drilling fluids that contain pollutants such as heavy metals and hydrocarbons. By means of the ICP-OES device, the concentration of metals in the drilling mud deposited in the accumulation pools (around the drill rigs), the drilling mud used in the well (initial, input, and output mud), the soil around the drilling rig, and the control sample can be determined. Comparison of metal accumulation volume with current standards (upper crust and the region’s soil) indicates that the initial drilling mud contains As, Cd, Mo, Cu, and Ag metals. Also, the outflow and associated cuttings are contaminated with Sb, showing a geological formation origin for this metal. In case of Pb, Ba, Cr, and Mn, the level of contamination is in a medium range wherein the source of the contamination is recycled mud and drilling rocks in the previous phases. Contamination of other metals is evaluated in the low range. Geo-accumulation index (Igeo), Enrichment Coefficient (EF), and Contamination Factor (CF) are used to determine the level of pollution. Results show that As, Pb, Ba, Mn, Mo, Cd, Co, Cu, and Zn have caused a lot of pollution in the area and their amounts should be controlled.
Show more [+] Less [-]Sustainability of Aluminium Oxide Nanoparticles Blended Mahua Biodiesel to the Direct Injection Diesel Engine Performance and Emission Analysis
2020
Rastogi, P. M. | Kumar, N. | Sharma, A. | Vyas, D. | Gajbhiye, A.
The study investigates the effect of aluminium oxide nanoparticles as an additive to Madhuca Indica (mahua) methyl ester blends on performance, emission analysis of a single-cylinder direct injection diesel engine operated at a constant speed at different operating conditions. The test fuels are indicated as B10A0.2, B10A0.4, B20A0.2, B20A0.4 and diesel respectively. The results indicate that the brake thermal efficiency for aluminium oxide nanoparticles blended biodiesel increases slightly when compared to the mineral diesel. The carbon monoxide (CO), unburnt hydrocarbon (HC) and smoke emission marginally decrease as compared to mineral diesel. Oxides of nitrogen (NOx) emissions are minimum for the aluminium oxide nanoparticles blended mahua methyl esters. Higher cylinder gas pressure and heat release rate were observed for aluminium oxide nanoparticles blended mahua methyl ester. From the study, the blending of aluminium oxide nanoparticles in biodiesel blends produces a most promising results in engine performance and also reduces the harmful emission from the engines.
Show more [+] Less [-]The Use of Astacus leptodactylus (Eschscholtz, 1823) as a Test Species for Toxicity Evaluation of Municipal Wastewater Treatment Plant Effluents
2020
Cikcikoglu Yildirim, N. | Aksu, O. | Tatar, S. | Yildirim, N.
This study evaluated the responses of biochemical biomarkers in Astacus leptodactylus exposed to treated municipal effluents discharged into Keban Dam Lake, Elazığ Elazig, Turkey. A. leptodatyclus were exposed to treated municipal effluents and Catalase (CAT), Superoxide dismutase (SOD) activity and lipid peroxidation (TBARS), glutathione (GSH) levels were measured as oxidative stress biomarkers. SOD activity was increased after exposing to treated municipal effluents for 24th and 96th h. CAT activities were decreased from 25.29 to 14.12 nmol/min/ml compared to control in the group exposed to treated municipal effluents for 24 h but it increased after 96 h exposure. GSH levels were decreased from 9.08 to 3.77 µM compared to control, but MDA levels were increased both at 24 th h and 96 th h after exposure to treated municipal effluents. CAT, SOD activities and MDA and GSH levels in the hepatopancreas of A. leptodactylus are sensitive and suitable biochemical biomarkers for evaluating the toxicity of the treated municipal effluent complex mixtures. Treated municipal effluents exposure was found to cause sub-lethal responses in A. leptodactylus suggesting oxidative stress.
Show more [+] Less [-]Carbon Monoxide Prediction in the Atmosphere of Tehran Using Developed Support Vector Machine
2020
Akbarzadeh, A. | Vesali Naseh, M. R. | NodeFarahani, M.
Air quality prediction is highly important in view of the health impacts caused by exposure to air pollutants in urban air. This work has presented a model based on support vector machine (SVM) technique to predict daily average carbon monoxide (CO) concentrations in the atmosphere of Tehran. Two types of SVM regression models, i.e. -SVM and -SVM techniques, were used to predict average daily CO concentration as a function of 12 input variables. Then, forward selection (FS) technique was applied to reduce the number of input variables. After converting 12 input variables to 7 using the FS, they were fed to SVM models (FS-(-SVM) and FS-(-SVM)). Finally, a comparison among SVM models operation and previously developed techniques, i.e. classical regression model and artificial intelligent methods such as ANN and adaptive neuro-fuzzy inference system (ANFIS) was carried out. Determination of coefficient (R2) and mean absolute error (MAE) for -SVM (-SVM) were 0.87 (0.40) and 0.87 (0.41), respectively, while they were 0.90 (0.39) and 0.91 (0.35) for ANN and ANFIS, respectively. Results of developed SVM models indicated that both FS-(-SVM) and FS-(-SVM) regression techniques were superior. Furthermore, it was founded that the performance of FS-(-SVM) and FS-(-SVM) models were generally a bit better than the best FS-ANFIS and FS-ANN solutions for short term forecasting of CO concentrations.
Show more [+] Less [-]Performance of a Dual Chamber Microbial Fuel Cell using Sodium Chloride as Catholyte
2020
Singh, K. | Dharmendra, .
Microbial fuel cell represents an emerging technology to attain electrical energy from wastewater. There are several alternative methods available for wastewater treatment; Microbial fuel cell is one of them, which generates green energy from wastewater for making a contribution to renewable sources of energy. This study states the performance of microbial fuel cell with different parameters i.e., catholyte, electrodes, and initial COD concentration. Sodium chloride was used as catholyte and graphite rods were used as both electrodes. The sodium chloride concentrations in the cathode and initial chemical oxygen demand have also been optimized. The optimum sodium chloride of 70 mM in the cathode solution generates the maximum power density of 408.98μW/m2. As the sodium chloride concentration increases in catholyte, the capacity for power production also increases. The voltage output of Microbial fuel cell increases when the initial concentration of chemical oxygen demand increases to a peak value of 1500 mg/l and if the value exceeds this limit, the performance of Microbial fuel cell (in terms of voltage) starts decreasing. The chemical oxygen demand removal efficiency of a microbial fuel cell with simple graphite electrode and graphite electrodes with coated iron were 79% and 90% respectively.
Show more [+] Less [-]Nitrate Bioremoval by Phytotechnology using Utricularia aurea Collected from Eutrophic Lake of Theerthamkara, Kerala, India
2020
Usharani, K. | Keerthi, K.V.
The aim of this study was to compare the selected aquatic plants ability to remove nitrate from wastewater. Excess of these nutrients in water can directly affect human health (methemoglobinaemia) or indirectly through the products of secondary pollution include eutrophication. Negative impact of nutrients excess in surface water often causes the destruction of water ecosystems, and therefore, common substances of these elements must be monitored and managed. Spectrophotometric technique was commonly used for quick and simple analyses of nutrients in waste water. There are calibration curves for each nutrient and for the determination of their concentration. Phytotechnology is one of the biological wastewater treatment methods or processes to eliminate nitrate contaminant from aquatic system. So as to avoid the eutrophic formation of fresh water and to determine the efficiency of nitrate utilization by specific aquatic plants which include Utricularia aurea and Salvinia molesta were collected from a eutrophic lake at Theerthamkara, Kerala. The samples were allowed to grow in nitrate solution for about one month at different concentrations. The optical density (OD) of nitrate solution at 410 nm was measured on alternative days of the experiment by using UV spectrophotometer. After 33 days of treatment periods, the maximum amount of nitrate removed in terms of percentage was found to be 95% by Utricularia aurea and 92% by Salvinia molesta at 100 ppm nitrate concentration. The results revealed that the aquatic plant (carnivorous) based system of phytotechnology was productively removed the nitrate load from the synthetic wastewater containing nitrate.
Show more [+] Less [-]Production of Nanofibers Containing Magnesium Oxide Nanoparticles for the Purpose of Bioaerosol Removal
2020
Dehghan, S. F. | Golbabaei, F. | Mousavi, T. | Mohammadi, H. | Kohneshahri, M. H. | Bakhtiari, R.
The present study aims at investigation of the performance of nanofibrous filter, containing magnesium oxide (MgO) nanoparticles, for bioaerosols removal from the air stream. It synthesizes two types of polyacrylonitrile (PAN) and PAN/MgO nanofibers via electrospinning technique, and investigates the antibacterial properties of the produced nanofibers through disk diffusion. The air containing staphylococcus epidermidis is introduced into the filter test rig by a nebulizer and air sampling from the microorganisms takes place before and after the filters by means of a cascade impactor with blood agar culture medium, with the filters, themselves, examined at two states of UVC radiation and dark. The mean diameters of PAN/MgO and PAN are 221.38±65.56 nm and 320.25±87.35 nm, respectively, with the mean length of the inhibition zone for these nanofibers calculated as 0 (for PAN) and 2.8 mm (for PAN/MgO). It turns out that the mean percentage of filtration efficiency is higher in case of PAN/MgO than PAN nanofiber filter; however, the former displays higher mean pressure drop than the latter. For both types of nanofibers under UVC radiation, the mean percentage efficiency for bioaerosol removal is higher than in the dark.
Show more [+] Less [-]Appraisal the Protective Effects of Cymbopogon Schoenanthus Extract against Reproductive Disorders and Carcinogenic Effects of Formalin in Experimental Male Rats
2020
Sief, M. M. | Sherif, S. M. | Abdel-Aziz, M. H. | Sherein, S. A. | Mona, M. A. | Ramzy, S.
Formaldehyde has been documented to be naturally present in many common foods. There has been a big public concern over the use of formaldehyde in the preservation of food. Also, it is commonly used as a chemical substance, usually in the life and can interact with many bio-substance in the human body. The present study target to investigate the protective effects of Cymbopogon schoenanthus (CS) extract against the reproductive and carcinogenic effects of formaldehyde on male rats. The Albino male rats were divided into equal six groups, first group: rendered as a control group; second group: received formalin (100 mg/kg bw) and third group and forth group: were received SC extract at (50 and 100 mg) respectively; fifth group and sixth group were received formalin (100mg /kg bw) + SC extract (50mg) and formalin (100mg /kg bw)+ SC extract (100 mg) respectively. At the end of the experiment the animals were scarified and blood samples were collected for measurement all tested parameters. The results showed that the oral exposure to formaldehyde at a dose of 100 mg/kg bw resulted in significant negative effects in all tested parameters, while the CS extract at tow doses (50 and 100 mg) alone or in combination with formalin restored the negative effects to normal levels compared with the untreated group. The histopathological examination was studied on testis tissues and the histopathological pictures showed the CS extract at tow mention doses had ameliorate the adverse effects that induced by formaldehyde hazards.
Show more [+] Less [-]A Review of Air Pollution and Solutions Way Management Related to Ribbed Smoked Sheets (RSS) Production of Community-Level Rubber Cooperatives in Thailand: Smoke, Soot and PAHs particles
2020
Kalasee, W. | Teekapakvisit, C.
In Thailand, RSS chamber of community-level rubber cooperatives can be classified into two models: old and new model, named after the years of their establishment. Hot gas as a heat supply from Para-rubber (PR) wood (Hevea brasiliensis) combustion is used for removing moisture from the natural rubber (NR) sheets. Smoke and soot particles from PR wood burning has effected to the quality of the NR sheet and the pollution in the workplace area and lead to health problems of the worker. Cascade impactors are equipment for measuring the smoke and soot particles size distribution from PR wood combustion. PAHs compounds from PR wood combustion were found 15 different PAHs components (Tekasakul et al., 2005; Furuuchi et al., 2006). Important methods in decreasing smoke and soot particles from combustion of PR wood for rubber smoking chamber are separation equipment and ventilation designed by computational fluid dynamics (CFD) technique. In this article, the separation method is focused on smoke and soot particle collection to maintain the quality of the NR sheet. This equipment is reviewed both indoor and outdoor, for example, an impaction wall, electrostatic precipitator, stainless-wire, etc. This review indicates that the ESP installing between the furnace and the smoking chamber is suitable to eliminate aerosol particles at the rubber smoking industry. In addition, CFD technique reports is aimed at collecting aerosol particles for decreasing smoke and soot particles emission from rubber smoking chamber is presented.
Show more [+] Less [-]The Effectiveness of the Ballast Water Exchange Method in Removal of the Heavy Metals in the Ballast Tanks of the Ships, Bushehr Port- Persian Gulf
2020
Tolian, R. | Javadzadeh, N. | Sanati, A. M. | Mohammadi Roozbahani, M. | Noorinejad, M.
Ships transport about 80 percent of world trade and transfer approximately three to five billion tons of ballast water internationally every year. Due to the likely presence of pollutants, the ballast water discharged by ships can have negative effects on aquatic ecosystems. This study was conducted on 10 ships that entered the Bushehr port to determine the effectiveness of the ballast water exchange method and also to specify the contents of heavy metals (Ni, Cd, Pb and Cu) in the water and sediment of the ships’ ballast tanks. The samples were collected from January 2017 to July 2018 during a cold and a hot season. The results indicate the values of heavy metals in the samples in this order: Ni> Cu > Pb > Cd. The heavy metals concentrations in the sediment samples did not exceed the standard of the National Oceanic and Atmospheric Administration (NOAA). Whereas, Cu and Ni in all water samples and Cd in samples 2 and 7 exceeded the NOAA quality standard value. A correlation analysis of the metals showed that the sources of heavy metals vary in water and sediment samples, except for Pb and Cu in sediment samples which a positively significant relationship were observed. The results also revealed that the ballast water exchange method cannot by itself be effective and an efficient management together with continuous monitoring seems to be essential to prevent pollution of the ballast tanks of the ships entering the Bushehr port.
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