Air ppllution
Maryam Bahiraei
Abstract
Introduction: Fuel stations are one of the major sources of BTEX emissions to the atmosphere. Benzene, toluene, ethyl benzene and gazeline isomers are BTEX aromatic hydrocarbons. BTEX compounds are the most abundant volatile organic compounds in atmosphere and surface water.These compounds can affect ...
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Introduction: Fuel stations are one of the major sources of BTEX emissions to the atmosphere. Benzene, toluene, ethyl benzene and gazeline isomers are BTEX aromatic hydrocarbons. BTEX compounds are the most abundant volatile organic compounds in atmosphere and surface water.These compounds can affect the health of employees, drivers and surrounding residents. Due to the risks of BTEX compounds on people's health and the possibility of emitting them from fuel stations, examining the concentration of these compounds and controlling them in fuel stations is essential and effective in preventing their complications. The aim of this study is investigation the amount of BTEX in the ambient air of hamadan fuel stations and its surrounding and to compare with occupational and respiratory air standards.Materials and Methods: The samples were collected according to the NIOSH method and the SKC adsorbent instruction by the individual sampling pump from indoor air and surrounding of Palestinian, Khansari and Forough fuel stations in Hamadan.The concentrationof BTEX compounds was extracted by dichrometan solvent and measured by GC/FID. The data were analyzed using SPSS software.Results: The mean of benzene, toluene, ethylenzene and xylene in Khansari fuel station were 1.23, 3.32, 0.31 and 1.43 mg/m3 respectively, in Palestine fuel station was 1.53, 4.14, 0.29 and 1.25 mg/m3 respectively and in Forough fuel station were 1.65, 2.23, 0.42 and 1.22 mg/m3, respectively. The highest concentration of BTEX compounds was located inside the fuel station and their concentration decreased by increasing the distance from the station. The mean concentrations of benzene in the air inside and distance 200m from the fuel stations were higher than EPA and in air inside and distance 50m from fuel station was higher than NIOSH guidelines. Also, the mean concentration of toluene in the air inside the Palestine fuel station was higher than the EPA guidelines.Discussion: The results showed that the dispersion of BTEX compounds in Hamadan refueling stations was caused by vehicles and gasoline evaporation during refueling. The reason for the decrease in the concentration of BTEX compounds by increasing the distance from fuel stations can be attributed to the production of pollutant concentrations in the yard stations, temperature conditions, wind direction and vehicles transportation. By increasing the distance from the station, as the production resources are more inside the station, from the concentration of BTEX compounds decreases by increasing the distance. Also, by increasing the distance from station, the wind airflow, lead to the distribution and dispersion of BTEX compounds and decreases its concentration. Employed personnel and drivers inside fuel stationsare confronted with benzene and toluene pollutants. As regards to short-term counterview with BTEX compounds causes effects such as stimulation and sensitivity of the skin, central nervous system problems (fatigue, headache, dizziness and loss of balance). Also in long-term encounters, in addition to the problems mentioned, they can affect the kidney, liver and blood. Therefore, more oversight should be carried out by petroleum product authorities and control actions to maintain the health of the people and reduce the pollutants in fuel stations, including leakage of tanks and pumps, and the possibility of recycling of gasoline vapors during refueling.
Air ppllution
Amir Abbasmofrad; Farhad Hamzeh; Omid Moradi; Nader Bahari
Abstract
The security and safety of metropolises today is the focus of men's government and urban diplomacy in all aspects of urban life. Also, one of the main components of the security threat is the environmental issue, including air pollution. The issue of air pollution and environmental crisis in metropolitan ...
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The security and safety of metropolises today is the focus of men's government and urban diplomacy in all aspects of urban life. Also, one of the main components of the security threat is the environmental issue, including air pollution. The issue of air pollution and environmental crisis in metropolitan areas, especially the city of Tehran in recent years has become one of the main concerns of those in charge of the authorities that trying to identify aspects of this crisis along with influential factors has become very important. The present article aims to investigate the relationship between air pollution and security with the mediating role of nanotechnology in the metropolis of Tehran. The present research in terms of descriptive-survey implementation method is based on the purpose of applied research and random sampling method. The statistical population of this study, due to their infinity, a statistical sample based on Cochran's formula, 384 people who are activists and experts in the fields of urban management, political geography, nanotechnology, environment, were selected. According to the research results, the implementation of air pollution reduction policies has an effect on increasing security by using nanotechnology and reducing air pollution and security has a significant and positive relationship with the mediating role of nanotechnology. Also, reducing air pollution and increasing security, reducing air pollution and nanotechnology, nanotechnology and increasing security have a significant and positive relationship.
Air ppllution
Samane Komeili; Abdollah Mostafaei; Morteza Jalali Lichei
Abstract
Nitrogen oxides are one of the most important pollutants in the air, which releasing into the atmosphere causes to produce of dangerous secondary pollutants. Identifying the various methods of reducing this pollutant in the chimney is an important guide for choosing an effective method to achieve the ...
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Nitrogen oxides are one of the most important pollutants in the air, which releasing into the atmosphere causes to produce of dangerous secondary pollutants. Identifying the various methods of reducing this pollutant in the chimney is an important guide for choosing an effective method to achieve the desired level of this pollutant according to the type of industry for experts. In this paper, methods for reducing nitrogen oxides in flue gas flow are reviewed. These methods include chemical processes such as plasma and non-plasma oxidation by an oxidizing agent, catalytic and non-catalytic reduction, electron irradiation, biological process, and physical adsorption processes on the surface. These methods separate nitrogen oxide from a gaseous stream and convert it into inert materials. These methods are very effective for industries that use old technologies and are highly polluting. The main technologies introduced in this article are among the four main methods with developed technology or they are close to development and can be used in Iranian industries.
Air ppllution
Razieh Farhadi; Mehdi Kargar; Ghasem Zolfagari
Abstract
Air pollution is a global threat to public and environmental health, especially in urban areas. Therefore, modeling is used to control and planing concentration of pollutants. In this paper, a model is proposed based on linear regression for short term forecasting of CO, PM10 and O3 based on meteorological ...
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Air pollution is a global threat to public and environmental health, especially in urban areas. Therefore, modeling is used to control and planing concentration of pollutants. In this paper, a model is proposed based on linear regression for short term forecasting of CO, PM10 and O3 based on meteorological parameters, and the results are presented. Data of meteorological parameters including humidity, pressure, minimum and maximum temperature, wind speed and wind direction (Birjand Meteorological Organization), and air pollution data (CO, PM10, and O3 concentrations) from the Birjand weather organization were prepared and used as daily average. SPSS16 software was used for linear regression modeling. The results showed that the highest correlation coefficient for CO pollutant with minimum temperature was 0.53 and the lowest correlation coefficient with the value of 0.166 was wtih the wind direction. The maximum correlation coefficient of PM10 contamination with wind speed was 0.33 and the lowest correlation coefficient of this pollutant with a pressure was 0.882. Finally, the highest correlation coefficient of O3 contamination with maximum temperature was 0.50 and also with regard to the regression coefficient obtained for carbon monoxide (R = 0.33) compared to the other two pollutants, has been obtained better.
Air ppllution
Mohammad Rastgari; Elmira Mousazadeh Namini; Nasrin Hashemi Tonekaboni
Abstract
Removing environmental pollution has become one of the main concerns of mankind today. Air quality in cities depends on the weather and the amount of pollutants produced. Today, air pollution is one of the most complex problems in human societies, which has had many negative effects on the health of ...
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Removing environmental pollution has become one of the main concerns of mankind today. Air quality in cities depends on the weather and the amount of pollutants produced. Today, air pollution is one of the most complex problems in human societies, which has had many negative effects on the health of living things, especially humans. In this study, the average monthly and annual concentrations of air pollutants in the air pollution measuring stations of Tehran Environmental Protection Bureau were evaluated in 91 to 97 years.The results showed that the highest concentration of major pollutants in Tehran in 1997 had a relatively decreasing trend compared to the previous year. Comparative statistics of the mean annual concentration of indicator pollutants show that CO levels in all stations decreased in 97 at most stations and O3 at all stations compared to the previous year, (it should be explained that the ozone pollutant at Shofuf station in 1997 to the geophysical station has been transferred). The average concentration of NO2, SO2, PM10 and PM2.5 pollutants in air pollution measuring stations and comparing it with the (WHO) standard indicates that all stations are in poor condition and above the standard level.
Air ppllution
Zahra Lotfi; Amir Abdoos; Habib Darparnian; Saeed Shokri
Abstract
Air pollution is one of the most important environmental problems in the last century that threatens human health. The purpose of this study is to investigate the average concentration of air pollutants, to detect the trend of pollutants change pattern, to identify high-risk months, air pollution index ...
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Air pollution is one of the most important environmental problems in the last century that threatens human health. The purpose of this study is to investigate the average concentration of air pollutants, to detect the trend of pollutants change pattern, to identify high-risk months, air pollution index and the impact of neighboring provinces on the air of Semnan province in 1399. In this study, the data of air pollution measuring stations in the west of Semnan province were examined. Monthly changes of pollutants in the west of Semnan province showed that the maximum monthly of most pollutants occurs in the cold season. The maximum concentration of cold months is caused by various factors such as increasing atmospheric stability, temperature inversions, decreasing surface wind speed and using more heat sources. Vehicles also have less fuel combustion in cold conditions. In addition, a significant part of this pollution is accumulated from neighboring provinces due to wind and geographical location within the province and causes changes in air quality in the province. Also, population increase, public fleet wear, high traffic of urban vehicles, industrial use, dust centers and geographical location are also factors affecting air pollution in the west of Semnan province.