خيارات البحث
النتائج 1 - 10 من 3,638
Techno-Economic Assessment of Removing BTEX Pollutants by Designing Thermal Oxidation Unit in a Bituminous Waterproofing Factory in Iran
2023
Soltanianzadeh, Zahra | Mirmohammadi, Mohsen | Zahed, Mohammad ali
Chemical degradation-based methods including oxidation have shown great promise for controlling benzene, toluene, ethylbenzeneandxylene isomers (BTEX) in waste gas. This study presents an approach in which the emission of BTEX compounds in a bituminous waterproofing (BW) production unit located in the city of Delijan, Iran has been controlled through process modification. The process is modified by introducing a thermal oxidation unit using an incinerator design. The process simulation has been performed with Aspen Hysys software and, key parameters in the oxidation process are identifiedandoptimized. Finally, the environmentalandeconomic performances of the incinerator were assessed to provide a decision support tool for the selection of this approach. Finally, the environmentalandeconomic performances of the incinerator have been assessed to provide a decision support tool for the selection of this approach. The results indicated that the formation of the oxidation unit had prevented the release of BTEX pollutants up to 98.5%. Moreover, the economic analysis illustrated that the rate of return on investment in the proposed project is 0.27. Thus, the potential for attracting capital will have positive impacts on the environmentalandeconomic indicators of the region.
اظهر المزيد [+] اقل [-]Brick Kilns Air Pollution and its Impact on the Peshawar City
2022
Hussain, Amjad | Khan, Naseer | Ullah, Munzer | Imran, Muhammad | Ibrahim, Muhammad | Hussain, Javid | Ullah, Hussain | Ullah, Irfan | Ahmad, Ikram | Khan, Muhammad | Ali, Meher | Attique, Faisal
In recent times, the brick kiln contributes to air pollution is one of the most emerging issues worldwide. In this research work, the Peshawar city, ambient air quality was measured, using a fixed air monitoring station to evaluate the impact of gaseous emission from brick kilns on ground level. In this study, the portable gas analyzer (PG-250) was used to quantify brick-based emitting carbon monoxide (CO), sulfur dioxide (SO2) and nitrogen oxide (NOx) from 3 brick kilns in the city of Peshawar. It was noticed that the average concentration of SO2 and NOx exceeds the National Environmental Quality Standards (NEQS) of Pakistan specifically, in terms of air quality. The brick kilns in District Peshawar have shown negative effects on the environment. It is necessary to take various measures to monitor the brick kiln embosom regularly before it becomes a significant risk for individuals. In conclusion, the impact of air pollution on physical activity and sedentary behavior at a specific time may be different.
اظهر المزيد [+] اقل [-]Chronological Studies of Traffic Pollution Using Elemental Analysis of Tree Rings: Case Study of Haatso-atomic Road
2020
Edusei, G. | Tandoh, J. B. | Edziah, R. | Gyampo, O.
Mitigation of atmospheric pollution has been a topic of concern over the past decades. In this study, tree rings have been used to reconstruct past climates as well as to assess the effects of recent climatic and environmental changes on tree growth. Vehicular emission is one of the major sources of pollutants in the atmosphere and this study focused on the Haatso-Atomic road which over the years has been a spot for heavy vehicular traffic. Swietenia mahagoni (Mahogany) tree was logged and the rings counted and age determined to be 61 years spanning from 1957 to 2018. X-ray fluorescence (XRF) was used to investigate the presence of the following heavy metals. Heavy metals (Cu, Mn, Zn, Pb, Cd and Ni) which ranged from (3.15—9.84mg/kg), (2.58 – 5.49 mg/kg), (8.18 – 15.78mg/kg), (0.12—0.60 mg/kg), (0.01—0.09 mg/kg) and (0.10 – 0.99 mg/kg) respectively, from vehicular emissions were determined for annual rings spanning from 1957 to 2018 and surprisingly an increasing trend was observed with some the heavy metals exceeding WHO guidelines. Tree growth rates were calculated through ring width measurements and related to annual precipitation data spanning over the sampling period. It was observed that wet seasons correlate with high growth rates of trees while low precipitations seasons related to low or no growth rate of trees.
اظهر المزيد [+] اقل [-]Evaluation of PM2.5 Emissions in Tehran by Means of Remote Sensing and Regression Models
2020
Jafarian, H. | Behzadi, S.
Defined as any substance in the air that may harm humans, animals, vegetation, and materials, air pollution poses a great danger to human health. It has turned into a worldwide problem as well as a huge environmental risk. Recent years have witnessed the increase of air pollution in many cities around the world. Similarly, it has become a big problem in Iran. Although ground-level monitoring can provide accurate PM2.5 measurements, it has limited spatial coverage and resolution. As a result, Satellite Remote Sensing (RS) has emerged as an approach to estimate ground-level ambient air pollution, making it possible to monitor atmospheric particulate matters continuously and have a spatial coverage of them. Recent studies show a high correlation between ground level PM2.5, estimated by RS on the one hand, and measurements, collected at regulatory monitoring sites on the other. As such, the present study addresses the relation between air pollution and satellite images. For so doing, it derives RS estimates, using satellite measurements from Landsat satellite images. Monitoring data is the daily concentration of PM2.5 contaminants, obtained from air pollution stations. The relation between the concentration of pollutants and the values of various bands of Landsat satellite images is examined through 19 regression models. Among them, the Ensembles Bagged Trees has the lowest Root-Mean-Square Error (RMSE), equal to 21.88. Results show that this model can be used to estimate PM2.5 contaminants, based on Landsat satellite images.
اظهر المزيد [+] اقل [-]The Use of Raw and Thermally-Modified Calcareous Sludge Generated in Stone Cutting Industry for Sulfur Dioxide Removal
2019
Loghmani, F. | Mirghaffari, N. | Soleimani, M.
Management of solid wastes is considered as an economic and environmental issue in the building stone industry. The current study uses raw and calcined calcareous sludge, generated in the stone cutting factories, in order to remove sulfur dioxide. Sludge characterization has been performed, using X-ray fluorescence (XRF), X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDX) analyses. The removal experiments of sulfur dioxide have conducted under different humid contents and adsorbent doses. The results showed that the higher the adsorbent dosage and humidity content, the greater the SO2 adsorption.. The calcination process at temperatures of 400, 500, 600, and 700℃ revealed that with rising calcination temperature and humidity content, the adsorbent capability is enhanced considerably. This method could be developed for the management of stone sludge produced from the stone cutting industry through its conversion into an effective and low-cost adsorbent for desulfurization process.
اظهر المزيد [+] اقل [-]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.
اظهر المزيد [+] اقل [-]Status and prediction of sulfur dioxide as an air pollutant in the city of Ahvaz, Iran
2017
Masoudi, Masoud | Asadifard, Elmira | Rastegar, Marzieh | Shirvani, Amin
The present research analyzes air quality in Ahvaz, a city in the south of Iran, paying special attention to sulfur dioxide (SO2). In order to prepare the average data in the city, measurements have been carried out between 2009 and 2010 in two different locations. Relations between sulfur dioxide and some meteorological parameters have been calculated statistically, using the daily average data. The wind data (velocity, direction), relative humidity, temperature, sunshine periods, evaporation and rainfall have been considered as independent variables. The RMSE Test showed that among different prediction models, the stepwise one is the best option. The average concentrations have been calculated for every 24 hours, during each month and each season. Results show that the highest concentration of sulfur dioxide occurs generally in the morning while the lowest concentration is found before the sunshine. In case of the monthly concentrations of sulfur dioxide, the highest value belongs to January, while the lowest one occurs in October. And as for the seasonal concentrations, it has been shown that the highest amounts belong to winter. Results show that quantities of SO2 in different seasons as well as the entire year can be estimated by climate parameters. Results also indicate that the relations between the SO2 and meteorological parameters are stronger than the entire year during the seasons.
اظهر المزيد [+] اقل [-]Status of CO as an air pollutant and its prediction, using meteorological parameters in Esfahan, Iran
2017
Masoudi, Masoud | Gerami, Soraya
The present study analyzes air quality for Carbon monoxide (CO), in Esfahan with the measurements taken in three different locations to prepare average data in the city. The average concentrations have been measured every 24 hours, every month and every season with the results showing that the highest concentration of CO occurs generally in the morning and at the beginning of night, while the least concentration has been found in the afternoon and early morning. Monthly concentrations of CO show the highest values in August and the lowest values in February. The seasonal concentrations show the least amounts in spring, while the highest amounts belong to summer. Relations between the air pollutant and some meteorological parameters have been calculated statistically, using the daily average data. The data include Temperature (min, max), precipitation, Wind Direction (max), Wind Speed (max), and Evaporation, considered independent variables. The relations between the pollutant concentration and meteorological parameters have been expressed by multiple linear regression equations for both annual and seasonal conditions, using SPSS software. Analysis of variance shows that both regressions of ‘enter’ and ‘stepwise’ methods are highly significant, indicating a significant relation between the CO and different variables, especially for temperature and wind speed in annual condition. RMSE test shows that among different prediction models, stepwise model is the best option.
اظهر المزيد [+] اقل [-]Modeling spatial distribution of Tehran air pollutants using geostatistical methods incorporate uncertainty maps
2016
Halimi, Mansour | Farajzadeh, Manuchehr | Zarei, Zahra
The estimation of pollution fields, especially in densely populated areas, is an important application in the field of environmental science due to the significant effects of air pollution on public health. In this paper, we investigate the spatial distribution of three air pollutants in Tehran’s atmosphere: carbon monoxide (CO), nitrogen dioxide (NO2), and atmospheric particulate matters less than 10 μm in diameter (PM10μm). To do this, we use four geostatistical interpolation methods: Ordinary Kriging, Universal Kriging, Simple Kriging, and Ordinary Cokriging with Gaussian semivariogram, to estimate the spatial distribution surface for three mentioned air pollutants in Tehran’s atmosphere. The data were collected from 21 air quality monitoring stations located in different districts of Tehran during 2012 and 2013 for 00UTC. Finally, we evaluate the Kriging estimated surfaces using three statistical validation indexes: mean absolute error (MAE), root mean square error (RMSE) that can be divided into systematic and unsystematic errors (RMSES, RMSEU), and D-Willmot. Estimated standard errors surface or uncertainty band of each estimated pollutant surface was also developed. The results indicated that using two auxiliary variables that have significant correlation with CO, the ordinary Cokriginga scheme for CO consistently outperforms all interpolation methods for estimating this pollutant and simple Kriging is the best model for estimation of NO2 and PM10. According to optimal model, the highest concentrations of PM10 are observed in the marginal areas of Tehran while the highest concentrations of NO2 and CO are observed in the central and northern district of Tehran.
اظهر المزيد [+] اقل [-]Status and preparation of prediction models for ozone as an air pollutant in Shiraz, Iran
2016
Masoudi, Masoud | Ordibeheshti, Fatemeh | Rajaipoor, Neda | Sakhaei, Mohammad
In the present study, air quality analyses for ozone (O3) were conducted in Shiraz, a city in the south of Iran. The measurements were taken from 2011 through 2012 in two different locations to prepare average data in the city. The average concentrations were calculated for every 24 hours, each month and each season. Results showed that the highest concentration of ozone occurs generally in the afternoon while the least concentration was found in the morning and at midnight. Monthly concentrations of ozone showed the highest value in August and June while the least value was in December. The seasonal concentrations showed the least amounts in autumn while the highest amounts were in spring. Relations between the air pollutant and some meteorological parameters were calculated statistically using the daily average data. The wind data (velocity, direction), relative humidity, temperature, sunshine periods, evaporation, dew point, and rainfall were considered as independent variables. The relationships between concentration of pollutant and meteorological parameters were expressed by multiple linear regression equations for both annual and seasonal conditions using SPSS software. Root mean square error (RMSE) test showed that among different prediction models, stepwise model is the best option.
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