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An Innovative Method to Allocate Air-Pollution-Related Taxes, Using Aermod Modeling (case study: Besat Power Plant).
2018
Tamjidi, Mahsa | Rashidi, Yousef | Atabi, Farideh | broomandi, parya
The present study applies the model of American Meteorological Society-Environmental Protection Agency Regulatory Model (AERMOD) to investigate NO2 emissions from Besat thermal power plant, which is fuelled by natural gas to function. Results indicate that the simulated concentration of NO2 based on AERMOD, does not exceed NO2 concentration limit, set by the Iranian Ambient Air Quality Standard. This shows that NO2 emissions from Besat power plant do not have any significant impact on nearby communities. The natural-gas-based power plant is capable of reducing the air pollution level. It also can decrease the hospital treatment costs, thus protecting public health. The modeling results shows that natural-gas-based power plant as a clean technology in power generation. Also, the AERMOD model has been used to determine the pollution source matrix of Besat power plant. An innovative idea has been implemented to not only determine air-pollution-related taxes and complexities but to solve the legal problem associated with it, also. As for the complexities, their determination entails two different methods: one, based on city's boundaries along with simulated amount of air pollutant concentrations in each receptor, and the other, based on the population of each receptor (i.e., the cities of Varamin, Eslamshahr, and Nasirshahr), which plays a vital role. According to the first approach, Varamin has the lion's share in the air pollution, caused by Best power plant. However, the second approach surprisingly shows that the largest portion belongs to Eshalmshahr, indicating the significant influence of its population.
显示更多 [+] 显示较少 [-]Biodegradation of Jet Fuel by Three Gram Negative Bacilli Isolated from Kerosene Contaminated Soil
2018
Adetitun, David | Akinmayowa, Victoria | Atolani, Olubunmi | Olayemi, Albert
Petroleum hydrocarbon contamination is a major global prevalent issue in the petroleum sector. This research focuses on evaluating biodegradation of three Gram-negative bacilli, isolated from cowpea planted soil, contaminated with kerosene. The Gram negative bacilli strains have been characterized and identified, using MicrobactTM ID24E systems for the identification of Enterobacteriaceae and common Miscellaneous Gram-Negative Bacilli (MGNB). The identified organisms include Aeromonas hydrophila, Vibrio parahaemolyticus, and Actinobacillus sp. with the biodegradation indices, monitored for the evaluation of their degrading abilities, being Optical density at 600 nm (OD600nm), pH, and emulsification stability. The chemical profile of single cultures and mixed cultures (consortia) on the jet fuel hydrocarbon has been determined by means of Gas Chromatography Mass Spectrometry (GC-MS), the results of which indicate that all the isolates have undergone above 70% reduction of the hydrocarbon substrates in terms of residual compounds. There has been 48 hydrocarbon compounds in the undegraded jet fuel which, following degradation process, decrease to 5, 13, 7, 10, 6, 9, and 10 compounds for Aeromonas hydrophila, Vibrio parahaemolyticus, Actinobacillus sp., Aeromonas hydrophila and Vibrio parahaemolyticus, Aeromonas hydrophila and Actinobacillus sp., Vibrio parahaemolyticus and Actinobacillus sp., Aeromonas hydrophila, Vibrio parahaemolyticus,and Actinobacillus sp., respectively. The degradation efficiency of the isolates have been relatively high and comparable to the control. Results from this study indicate that all the strains, especially the consortia, are potential candidates for remediating the problem of hydrocarbon contamination in the environment.
显示更多 [+] 显示较少 [-]Common Waterborne Diseases Due to Bacterial, Fungal and Heavy Metal Contamination of Waters: A Case Study from Nacharam Area of Hyderabad, India
2018
Das Sharma, Mala | Padmalatha, P.
Nacharam and its surroundings, located inside the city of Hyderabad in Telangana State, India, is vulnerable to water-borne diseases; therefore, the present research works on concentrations of dissolved hexavalent chromium (57-263 mgL-1), lead (34-65 mgL-1), cadmium (2.3-22.4 mgL-1), and nickel (from below detection limit to 6.5 mgL-1) in different surface water and groundwater bodies of this area. Results indicate that with the exception of nickel, the majority of studied water bodies and aquifers of the area are contaminated, to variable degrees, with dissolved heavy metals. Also health-affecting bacterial and fungal colonies have been found in drinking water and groundwater bodies of the area. These findings collectively point at impending health threats to the residents of the area, thus this study has conducted a health survey, whose data indicate that about two third of the residents are affected by waterborne ailments, including hair fall, skin rashes, tooth decay, diarrhea, and joint pain. Hair fall is one of the major problems affecting about 40% of the area population. Other waterborne health-related issues are faced by relatively smaller numbers of residents (10% or less). Based on the results from this study, it is recommended not only to conduct periodic analyses of water samples used for drinking and other purposes, which would assist the government and local authorities in taking necessary steps to prevent groom and spread of microorganisms, but also to monitor other anthropogenic activities, potentially capable of contaminating water sources, .
显示更多 [+] 显示较少 [-]Modeling of Air Pollutants’ Dispersion by Means of CALMET/CALPUFF (Case Study: District 7 in Tehran city).
2018
Joneidi, Neda | Rashidi, Yousef | Atabi, Farideh | broomandi, parya
The current study aims at modelling the dispersion of two pollutants, namely CO (carbon monoxide) and SO2 (sulfur dioxide) released from District 7 of Tehran Municiaplity, from 20 main line sources, by means of CALPUFF modeling system. CALPUFF is a non-steady state puff modeling software which employs meteorological, terrain, and land-use data to effectively simulate air pollutants' dispersion from a given source. CALMET software has been applied to provide meteorological conditions within the study domain. The study has been carried out on September 30, 2012 and shows that the modeled concentrations have been below both Iranian air ambient standard and NAAQS standard for CO and SO2. It also compares the measurements from the monitoring station of Setad Bohran, showing that the simulated hourly mean concentrations of the SO2 and CO do not follow similar temporal patterns for measurement values. For the absolute value, model results seem to be highly underestimated, compared to the monitored data (R2 = -0.41).
显示更多 [+] 显示较少 [-]Preparation and Characterization of Nano-lignin Biomaterial to Remove Basic Red 2 dye from aqueous solutions
2018
azimvand, jafar | didehban, Khadijeh | mirshokraie, s.ahmad
The present study prepares alkali lignin (AL) via acidification of black liquor, obtained from a pulp and paper factory. The average molecular weight of AL (equal to 2,530 g/mol) has been determined with gel permeation chromatography. AL has been modified by ethylene glycol, while lignin nanoparticles (LN) has been prepared through acid precipitation technology, their size being assessed by means of DLS to show that the average diameter of the nanoparticles at pH = 4 has been 52.7 nm. Afterwards, it has used AL and LN to remove Basic Red 2 (BR2) from aqueous solutions. The absorbent structures and morphologies of AL and LN have been investigated using SEM, and FT-IR spectroscopy. The optimal conditions for the absorption of AL and LN, using 0.1 gr of the absorbent, include 100 min of duration, at pH of 7, and an initial dye concentration amounting to 100 mg/L. Furthermore, the absorption amount has been mathematically described as a function of experimental parameters, modeled by means of Response Surface Methodology (RSM). A central composite design (CCD) has been applied to evaluate the impacts of four independent variables. Optimum absorption values, obtained via empirical methods, completely match with the values, calculated by the program called Design-Expert. Both absorbent AL and LN show agree with Langmuir Isotherm with maximum absorption capacities of AL and LN being 55.2 mg/gr and 81.9 mg/gr, respectively. The experimental results show that both absorbent LN and AL follow both pseudo-second kinetic and the intraparticle diffusion models.
显示更多 [+] 显示较少 [-]Assessment of Heavy Metals and Microbial Load of Groundwater Samples from Ibadan Metropolis Nigeria
2018
Salaudeen, I.A. | Ogunbamowo, Paul | Rasheed-Adeleke, A.A. | Olaniyi, A.A.
The present study investigates groundwater quality in terms of heavy metals level and microbial contamination as well as the impact of bleaching powder on microbial load of groundwater samples in close proximity to a surface water body inside selected areas of Ibadan Nigeria. To do so, it collects nine water samples from three boreholes and six hand-dug wells from six locations, namely Eleyele, Wofun-Olodo, Oluyole Industrial Estate, Ogunpa, Olorunsogo, and Ojoo, keeping them in 750 mL plastic bottles. The samples are then divided by two, giving a total amount of 18 samples, with 3 and 6 duplicates apiece being treated with bleaching powder and the rest remaining untreated. Both sample sets have been analysed for water quality parameters such as pH, biochemical oxygen demand, and chemical oxygen demand, assessed using standard methods. The coliform count has been determined, using the pour plate method while heavy metal has been set by means of Atomic Absorption Spectrophotometer (AAS) after nitric acid digestion. Results show that the pH ranges within 6.0-6.5, BOD within 1.67-4.33mg of O2/L, and COD within 2.93-9.43, while heavy metal concentration is from 0.013 to 0.047 mg/L for lead, ND to 0.023 mg/L for chromium, and ND to 0.010 for cadmium. What is more, the coliform count in the samples is between 0.00 and 913.33 CFU/mL. Most of the samples exceed the WHO limits for heavy metals in drinking water, having significant levels of microbial contamination. Bleaching powder treatment alleviated the level of pollution to varying degrees; therefore, constant monitoring of groundwater source and treatment before drinking is of utmost importance.
显示更多 [+] 显示较少 [-]Health Risk Assessment of Chromium-Accumulated Fish and Vegetables at Gulshan Lake of Bangladesh: A Case Study
2018
Mohinuzzaman, M. | Saadat, A.H.M. | Mostofa, K.M.G. | Islam, S.M.N. | Hossain, S.M. | Tareq, S.M.
The present study evaluates health risk assessment for inhabitants who are exposed to chromium in fishes and vegetables of the Gulshan Lake. In the fish, chromium concentration has amounted to 2.2 to 149.7 mg/kg, while in vegetables leaf and vegetables stem it has been 5.6 mg/kg and 12.0 mg/kg, respectively. What is more, in sediment it has been 179.5 to 308 mg/kg and in water, 4.0 to 16.9 mg/l. Higher accumulation of chromium (149.7 mg/kg) has been found in a fish species, relatively most affordable for poor people, called Pangas (Pangasius pangasius). Therefore, due to consumption of this fish the resultant non-cancer health hazard indices to people, living nearby Gulshan Lake has been almost 10 times greater than those induced by safe average daily dosages of the respective chemical. Vegetable pathway is still safe in terms of non-carcinogenic health hazard but may be very likely to act as an additive. It is therefore important to immediately take some remedial measures to not only reclaim Gulshan Lake but prevent any further pollution also.
显示更多 [+] 显示较少 [-]Assessment of Heavy Metals Pollution in Water and Sediments of Djendjen River, North Eastern Algeria
2018
Krika, Abderrezak | Krika, Fouad
Water and sediment samples have been collected from five different stations, located along Djendjen River between February and June, 2016 so that the concentrations of Cd, Ni, Zn, and Cu could be determined. The extent of the sediment pollution has been assessed, using the multiple pollution indices, namely Contamination Factor (CF), Pollution Load Index (PLI), and the geoaccumulation index (Igeo).The distribution of trace elements in water and sediment follows Ni>Zn>Cd>Cu and Zn>Ni>Cu>Cd, respectively. The water sample analysis from Djendjen River shows that the total concentrations of Cu, Ni, Cd, and Zn have been lower according to the references. In comparison, sediment mean metal concentrations with several environmental contamination parameters, like probable effect level (PEC) and background levels, indicates that the concentrations of all investigated elements are lesser than PEC, except for Ni, but higher than the background levels. The Igeo values reveal that Cd has been the most accumulated compared to the other metals. Contamination Factor (CF) confirms that the sediment samples have been moderate in terms of all studied metals contamination. The Pollution Load Index (PLI) values have been above one (>1), indicating an advanced decline of the sediment quality.
显示更多 [+] 显示较少 [-]Contamination from Petroleum Products: Impact on Soil Seed Banks around an Oil Storage Facility in Ibadan, South-West Nigeria
2018
Akande, Funmilola | Ogunkunle, Clement | Ajayi, Sunday
The plants, grown in the soils around a Fuel Holding Depot of the Nigerian National Petroleum Corporation, Ibadan, Oyo state, Nigeria have been investigated in this research in terms of their density and species composition so that the impact of contamination by petroleum products on soil seed banks could be determined. The study has used designated plots (25m by 25m) in a site, contaminated by petroleum products, as well as a non-contaminated site. In each plot, replicate soil samples have been collected randomly at 0-5 cm, 5-10 cm, and 10-15 cm, with the soil samples being subjected to emergence of seedling test for three months in order to determine the species composition, species density, and seed viability at different soil depths. Results show that 17 species from 14 families with a total seedling density of 975 seedlings (19,073 seeds/m2) have been encountered in the seed bank of the non-contaminated soil, whereas just one species with 339 seedlings (6,632 seeds/m2) has been recorded in the contaminated soil. Herbaceous species notably, Spermacoce ocymoides, Spermacoce verticillata, and Peperomia pellucida dominate the seed bank of the non-contaminated soil, whereas Eleusine indica is the sole species, encountered in the seed bank of the contaminated soil. There is a general reduction in seed viability as the soil depth is increased. In conclusion, contamination by petroleum products narrow the species composition and density of soil seed bank, though has no effect on seed viability, irrespective of soil depth. Eleusine indica, being the only species encountered in the contaminated soil, may be tolerant to petroleum hydrocarbon, thus portending useful potentials for phytoremediation.
显示更多 [+] 显示较少 [-]Health Risk Assessment of Heavy Metals in Soil from the Iron Mines of Itakpe and Agbaja, Kogi State, Nigeria
2018
Aluko, Tope | Njoku, Kelechi | Adesuyi, Adeola | Akinola, Modupe
The study evaluates associated health risks of heavy metals in the soil to inhabitants of two mining areas of Nigeria. For so doing, it collects and analyses nine homogenous soil samples for their lead, copper, cadmium, zinc, and chromium levels, using AAS. The samples are then used to calculate health risks to adults and children. For adult population in Agbaja community, the calculated hazard quotients fall below one in all considered pathways. Hazard index values for all the pathways are also less than one, taking the following order: Cu>Cr>Pb>Cd>Zn. It is shown that for all considered heavy metals, the adult population in Agbaja mining community was not at any risk of non-carcinogenic effects from these metals. As for the children in Agbaja, the calculated HQ values for Cd and Zn have been less than one in all the pathways, while the HQ values for Pb, Cr, and Cu have significantly surpassed 1, with the ingestion route being the main pathway. The HI values have been in the following order: Cu>Cr>Pb>Cd>Zn, which poses serious non-carcinogenic health risks to the children, living around this community. The carcinogenic risk has been calculated based on Pb, Cd, and Cr, with the former (Pb) proven to be the highest contributor to cancer risk. USEPA considers acceptable cancer risk within the range of 1×10−6 to 1×10−4. Though insignificant in its values, carcinogenic risk for adults in Agbaja (2.95×10-4) and Itakpe (4.71×10-4) and for children in Itakpe (4.47×10-4) have been higher than the acceptable values. Hence, the adults are more at risk, for whom ingestion is the main contributor to excess lifetime cancer risk, followed by dermal pathways. Considering the health hazards, entailed by the accumulation of these heavy metals, on human health, mining sites and areas require to get monitored properly.
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