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.
MOHAMMAD SHAHMOHAMMADI; Yarmohammad Bay; PARVANEH Kiani
Abstract
Introduction: Air pollution is a crisis that many countries around the world are currently facing. The city of Tehran has been facing the problem of air pollution for a long time and its solution has become one of the important social demands and has found international dimensions. The phenomenon of ...
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Introduction: Air pollution is a crisis that many countries around the world are currently facing. The city of Tehran has been facing the problem of air pollution for a long time and its solution has become one of the important social demands and has found international dimensions. The phenomenon of air pollution in Tehran has been affecting Tehran for many years, and in the past several years, with the arrival of the cold and winter season, the residents of the capital face a serious problem, and despite all the measures taken to prevent pollution, we still see days when schools are closed and the plan of even and odd cars also continues; but pollution is strongly standing. The results of previous studies indicate the influence of various factors including geographical factors, natural features of the city, temperature inversion and industrial pollutants in air pollution.The purpose of this study is to provide a model for individuals with air pollution in Tehran.Materials and Methods: The current research is applied in terms of the type and purpose of the research, and descriptive-analytical in terms of the data collection method. In this research, after identifying the factors affecting the air pollution of Tehran city, using the opinion of relevant experts, the researcher has used the interpretive structural modeling (ISM) technique to level and interpret the conceptual relationships of the mentioned indicators. By reviewing the research literature and taking the opinion of experts, the issue is identified in the form of six indicators (temperature inversion, geographical-climatic location, pollution of factories and refineries, low quality of vehicles and fuel consumption, low green space per capita, high population density of Tehran) Took; Then, a structured matrix questionnaire was developed to determine the interrelationships of these indicators. The data obtained from the questionnaire were analyzed using interpretive structural modeling and plotted on five levels in an interactive network.Results: The results of this research showed that both industrial factors and climatic factors can be effective on air pollution in Tehran. According to result of the modeling, "pollution of factories and refineries" index was at the highest level. Therefore, transferring factories in the city and preventing the construction of new factories in the city as a solution can help reduce air pollution in Tehran.Discussion: When a temperature inversion occurs, the air becomes stable and particles accumulate in the range of the inversion layer and increase the intensity of air pollution. Regarding the pollution of factories and refineries, most of the processes that produce air pollution in industries, after the heating process, are dedicated to the process of combining materials, and air pollutants in the form of smoke and suspended particles include the most cases. Also, the combustion process in the engine of old and low-quality cars is not done well, and this is the main reason for the production of carbon monoxide. Climate controls the pollution conditions of Tehran city through changing its elements such as temperature, precipitation, pressure and wind. Also, compared to the big cities of the world and their population, Tehran is ranked 120 to 130 in terms of size, but in terms of density per square kilometer, it is ranked between 25 and 30. This means that in this city, the population has accumulated more than the ecological capacity and urban area, which causes crises such as air pollution.
Zahra Soltanian zade; Mohsen MirMohammadi; Mohammad Ali Zahed
Abstract
Introduction: Aromatic hydrocarbons such as benzene, toluene, ethylbenzene and xylene isomers (BTEX) are pollutants in industrial plants that cause problems in various sources, especially air. Elimination of these toxic compounds, even to a very small extent, from these constant sources of pollutants ...
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Introduction: Aromatic hydrocarbons such as benzene, toluene, ethylbenzene and xylene isomers (BTEX) are pollutants in industrial plants that cause problems in various sources, especially air. Elimination of these toxic compounds, even to a very small extent, from these constant sources of pollutants is important not only from an environmental but also from an economic point of view. Nowadays, the rapid industrialization of societies, especially developing countries, to meet the needs of citizens is recognized as the main cause of air pollution. Therefore, maintaining environmental standards is necessary to reduce the potential for pollutions and support sustainable development. Waterproofing production plants are one of the main sources of emissions of this group of pollutants, so the implementation of control measures and optimization of the performance of these industrial units in Delijan city as the capital of Waterproofing production is necessary and undeniable.
Material and Methods: In this study, the process of removing BTEX contaminants from Izogam Parsian Delijan factory has been evaluated and studied through simulation and process modification based on insulator design and using thermal oxidation of pollutants (BTEX) method. Questions related to the efficiency and environmental benefits of designing incinerator serve as the primary motivation for the present work. The purpose of this study is to help this evidence by assessing the environmental and technical evaluation of the performance of the incinerator unit in a BW production plant located in Delijan-Iran. Moreover, energy consumption and pollutant emissions of system have been optimized by changing the temperature and residence time of incinerator using SPSS software. It should be noted that the process of removing BTEX contaminants has been accomplished by simulation using Aspen Hysys software. In this regard, the process modification based on the Incinerator designing and using the thermal oxidation method has been evaluated.
Results: Based on the results, the temperature and residence time in optimal conditions are 732 and 0.84, respectively. Furthermore, the incinerator's control efficiency (CF) reveals that 98.5% of BTEX compounds in the exhaust gases were removed. It should be noted that the system's energy efficiency has also improved significantly in such a way that the amount of fuel consumed by the system in optimum condition has decreased by 23% compared to the initial state.have been optimized by implementing software such as SPSS and hardware elements. The results of using the incinerator in this study, the rate of control efficiency (CEF) of the device in removing the desired compounds is reported to be 98.5%. Also, the energy consumption index in this case, compared to the performance of the system without insulator in the same mode, has caused a 23% reduction in fuel consumption.
Discussion: The optimization results revealed that using incinerator in certain condition can be considered as an applicable solution for removing BTEX from industrial activities. In this regard, temperature and residence time can be determined as two significant operating indexes affecting the pollutants emission and energy consumption. According to the results, the proposed method has acceptable environmental and economic performance thus, It is also suggested the possibility of large investments to reduce the effects of BTEX pollutants in the region by coupling them to renewable energies.
Azam Shahbeik; Rahele Pourmazaheri; Ahmad Taheri
Abstract
Introduction: One of the significant challenges metropolises faces is air pollution, which has many adverse effects on human health and the environment. Karaj, as an industrial city situated close to the country's major industries and power plants, is severely affected by air pollution from both mobile ...
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Introduction: One of the significant challenges metropolises faces is air pollution, which has many adverse effects on human health and the environment. Karaj, as an industrial city situated close to the country's major industries and power plants, is severely affected by air pollution from both mobile and stationary sources. The most important study carried out in the field of air pollution in Karaj city can be considered the air pollutant emission inventory of this city, which is stated for criteria pollutants in two categories of stationary and mobile sources, separately for each source.Methodology: After upgrading the air quality monitoring stations in this city, the current study can be considered the first comprehensive study of air pollutants in terms of their temporal and spatial trends. This study measured air quality in stations equipped with the analyzers of four gaseous pollutants, including ozone, carbon monoxide, nitrogen dioxide, and sulfur dioxide, along with two particulate pollutants, including particulates smaller than 2.5 and 10 microns. Furthermore, the city's air quality index, obtained from the total of monitoring stations, was analyzed.Results: The study finds that particulate matter smaller than 2.5 microns and ozone are the main pollutants in Karaj in hot and cold seasons, respectively. The other pollutants exceed the allowable air quality index, rarely. For a period of one-year, particulate matter smaller than 2.5 microns and ozone put the air quality index in the range of unhealthy for sensitive groups and unhealthy for the entire city of Karaj for 94 and 18 days, respectively. Also, this study investigated the pollutant transport effect using the combination of pollutant concentration data, wind speed, and direction. The dominant directions of pollutant transport to that station were determined for each air quality monitoring station. Based on the results of the present study, for PM2.5, as the most critical air pollutant in the city of Karaj, it can be found that the highest concentration and therefore, the most days with the index in the unhealthy range for PM2.5 has been registered in Metro and Zone 3 stations, in the cold seasons of the year (autumn and winter), respectively.Discussion: By examining the location of these two stations, they can be evaluated as traffic stations. Since the Metro station is located in the Karaj metro area, it is not only affected by the pollution caused by the transport fleet on the routes adjacent to the station (the most important of which is the Karaj-Qarvin freeway), but also the traffic and stops of buses and taxi fleets, which can cause the emission of suspended particles in that area. On the other hand, the station of zone 3 is located at a very short distance from Eram Boulevard, which is strongly affected by the pollutants emitted by the transport fleet on this route. Due to the secondary nature of Karaj's main pollutants, such as ozone in the warm season and a high portion of suspended particles smaller than 2.5 microns in the cold season, it is necessary to reduce air pollution through modeling that incorporates photochemical reactions in the atmosphere.
Mehdi Nejati; Zein Al-Abedin Sadeghi; Mohammad Ali Arabpour
Abstract
The increase in greenhouse gas emissions in recent years has caused great concern to many communities and environmentalists; one of these important greenhouse gases is carbon dioxide (CO2). In this study, using important economic variables and indicators and time series data series of 1970-2018, which ...
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The increase in greenhouse gas emissions in recent years has caused great concern to many communities and environmentalists; one of these important greenhouse gases is carbon dioxide (CO2). In this study, using important economic variables and indicators and time series data series of 1970-2018, which were divided into 5 separate groups with a set of data, and predicted the amount of CO2 emissions in Iran. For this subject, deep learning models of machine learning subset have been used. It was a multivariate issue and a set of objectives that predicted the amount of CO2 emissions for the next 5 years (5 years after 2018) and finally compared the forecasts for 2019 and 2020 with the actual CO2 of these years to verify the forecasts. The results obtained for all 6 experimental groups show that the amount of CO2 emissions in Iran will follow an upward trend in the coming years and by 2023 the amount of CO2 emissions will reach 850 to 900 million tons, which could be an environmental and dangerous disaster. Be for humans. Therefore, it is suggested that the government use a long-term plan with emphasis on important groups, culture building in the community and the establishment of more specific laws to control the amount of CO2 emissions.
Omidali Adeli
Abstract
Although economic growth and development in different countries has increased economic prosperity, but also environmental pollution threatens human life. The purpose of this study is to investigate the factors affecting air pollution by emphasizing the emission of carbon dioxide in among the countries ...
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Although economic growth and development in different countries has increased economic prosperity, but also environmental pollution threatens human life. The purpose of this study is to investigate the factors affecting air pollution by emphasizing the emission of carbon dioxide in among the countries of the ECO region from 2000 to 2018 with an emphasis on financial development. To investigate the effect of financial development on environmental pollution, the Panel Data econometric method has been used and the model coefficients have been estimated with Eviews 10 software. The dependent variable of the research is the amount of carbon dioxide emissions in terms of tons per year and the independent variable is the combined index of financial development. Two control variables including GDP and energy consumption are also included in the model. In the long run, the effect of financial development on carbon dioxide emissions in the ECO countries is positive and significant. Also, the effects of GDP and energy consumption on carbon dioxide emissions are positive and significant. The coefficient of determination of the model is equal to 98%, which indicates the high descriptive power of the model. Although increasing the level of economic activity increases welfare in different societies, but given that increasing the level of economic activity, especially industrial activity, increases the emission of carbon dioxide and biodegradation. یEnvironment in ECO member countries, economic policy makers of these countries should work together to implement the necessary policies and strategies to control and reduce emissions of carbon dioxide and other environmental pollutants.
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.
Environmental Economics
Abolghasem Golkhandan; Somayeh Sahraei
Abstract
Expand the usage of Internet and consequently reducing the digital divide between developing and developed countries, shows the study of effect this variable on the energy consumption and air pollution in developing countries is important. In this regard, the main objective of this paper is to examine ...
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Expand the usage of Internet and consequently reducing the digital divide between developing and developed countries, shows the study of effect this variable on the energy consumption and air pollution in developing countries is important. In this regard, the main objective of this paper is to examine the impact of the Internet's influence on energy consumption and CO2 emission in Iran Using time series data 1995-2016. The results using co-integration five-step Johansson (1992) method showed a positive impact of Internet on the per capita energy consumption in the long term. A one percent increase in the number of Internet users (per 100 people), in the long run, increase the per capita energy consumption in Iran by 0.19 percent. Accordingly, the move to the policies and programs that take advantage of the Internet to reduce energy consumption in the country is essential. Also, the long-term impact of the Internet on air pollution is positive, but it is negligible. So that a one percent increase in the number of Internet users (per 100 people), in the long run, increase the level of CO2 emissions in the country by about 0.06 percent. Accordingly, it can be said that the increase in Internet usage is not a serious threat to air pollution in Iran.
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.
Environment Assessment
Roya Taji; Mozhgan Ahmadi Nadoushan
Abstract
In recent years, population growth, increasing vehicles, and industrial development have caused air pollution. One of the major disasters, creating significant problems for human and endangering their health is air pollution. The main objective of the present study was to select best sites for air pollution ...
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In recent years, population growth, increasing vehicles, and industrial development have caused air pollution. One of the major disasters, creating significant problems for human and endangering their health is air pollution. The main objective of the present study was to select best sites for air pollution monitoring stations in zones 1 and 3 of Isfahan city using fuzzy technique and analytical hierarchy process (AHP). Accurate monitoring of the air pollution condition requires accurate and appropriate dispersion of monitoring stations throughout the study area, so that the optimal locations of these stations can be selected using fuzzy and AHP methods. In the present study, considering the necessity of determining the location of air pollution monitoring stations, the best sites for these stations were selected based on important criteria such as distance from market, recreation areas, parks, parking areas and existing stations using fuzzy and AHP methods. The results showed that Fuzzy-AHP method was flexible and accurate method to determine the appropriate areas for air pollutant monitoring stations.