Sona Kebriaeezadeh; Jamal Ghodduosi; Ali Asghar Alesheikh; Reza Arjmandi; Seyed Alireza Mirzahosseini
Introduction: Rapid and uncontrolled expansion of cities, increased traffic, industrial enterprises and low-quality fuels, as well as urban morphology parameters and climatic conditions are among the factors affecting air pollution in urban areas. In Iran, the metropolis of Isfahan, which is the third ...
Introduction: Rapid and uncontrolled expansion of cities, increased traffic, industrial enterprises and low-quality fuels, as well as urban morphology parameters and climatic conditions are among the factors affecting air pollution in urban areas. In Iran, the metropolis of Isfahan, which is the third largest urban area in the country, has an increased air pollution due to the extensive development of industrial enterprises, and population and urban growth. Therefore, in order to find the factors affecting the trend of air quality changes, trend analysis and evaluation of the relationship between land use parameters, industrial development and traffic situation with air pollution indicators were studied.Material and methods: In order to evaluate the trend using measured periodic data and simple correlation and regression methods of seven air pollutants including PM2.5, PM10, CO, SO2, NO, NO2 and NOX as dependent variables and meteorological parameters, type of land use, industry development and vehicles were analyzed as independent variables. Also, SPSS software was used to test the normal distribution of data sets including the concentration of air pollutants and meteorology from 1387 to 1394, in 10 air pollution measuring stations and three meteorological stations in Isfahan metropolis.Results and discussion: The results of the study show that the average annual concentration of PM (PM10 / PM2.5), NO and CO decreased and the average annual concentration of SO2, NO2 and NOXincreased. In addition, the average annual rainfall, temperature and wind speed increased while the trend of relative humidity in the study area did not change significantly. It was also found that the trend of residential, educational, commercial, public services, transportation and the number of industrial units and vehicles has increased significantly. However, the amount of agricultural land, green space and industrial areas has significantly decreased in the study area. The results of stepwise regression analysis showed that changing the use of agricultural land to residential areas and increasing wind speed may have caused the decreasing trend of NO, CO, and suspended particles in the study area. In addition, the increasing trend of transportation can be the most important reason for the increase in NO2 concentration. On the other hand, due to the increasing trend of NOX emissions and significant negative correlation with green space and positive correlation with transportation and industrial areas and the result of stepwise regression model, it can be concluded that reducing green space and an increase of 99.5% in the area of transportation use increases the NOX concentration in the study area. In addition, the size of utility centers increases the concentration of SO2 and there is a negative relationship between the concentration of PM2.5 and SO2 (as the concentration of SO2 increases, the concentration of PM2.5 increases).Conclusion: It is noteworthy that the relationship between air quality indicators as dependent variables with independent variables in urban areas is complex and it is not clear which specific factor or parameter is the most important scenario of air pollution in an urban context. Therefore, more detailed research is needed.
Maryam Chehrehei; Seyed Alireza Mirza Hosseini; Nabiollah Mansouri; Youssef Rashidi; Mohammad Hassan Behzadi
Introduction: Volatile organic compounds such as gasoline vapors have adverse effects on the environment. In the metropolis of Tehran, gasoline is considered a toxic and dangerous pollutant. One of the most important sources of gasoline vapor emissions in the environment is storage tanks for petroleum ...
Introduction: Volatile organic compounds such as gasoline vapors have adverse effects on the environment. In the metropolis of Tehran, gasoline is considered a toxic and dangerous pollutant. One of the most important sources of gasoline vapor emissions in the environment is storage tanks for petroleum products, operational processes, and the number of emptying and loading of storage tanks and gasoline sales activities at gas stations.Material and methods: To calculate the emission of gasoline vapors from storage tanks of petroleum products in gasoline supply channels, the TANKS 4.09 software was used. Data such as physical characteristics of the reservoir (dimensions), number of loading times of reservoirs, spatial characteristics of reservoirs (climatic parameters), specifications of petroleum products stored in the reservoir, etc. were entered into the software for 22 districts of Tehran.
Results and discussion: According to the outputs, the emission of gasoline vapors from 412 tanks installed in 148 gas stations located in 22 districts of Tehran was about 7702356 liters per year. About 56.78% of it is released in the warmer 6 months and about 43.21% in the colder 6 months of the year. In the spring, summer, autumn, and winter seasons, about 27.06%, 29.56%, 22.63%, and 20.73% gasoline vapors are released into the environment. Emissions occurred more in 6 months of the year, with most of the emissions of gasoline vapors being from mid-May to mid-November. By comparing the percentage of vapor emission with the percentage of the number of loading times, percentage of operating capacity, number of tanks, and percentage of gas stations in Tehran, it can be concluded that effective factors in increasing gasoline vapor emission are a high number of loading times, high maximum operating capacity, number of tanks, and low number of gas stations. The highest emissions are related to regions 4, 2, and 15, respectively, which have the highest statistics in these cases according to surveys and classification based on maximum gasoline sales, number of loading times, maximum operating capacity, and number of tanks.Conclusion: Considering the number of gasoline sales (about 4219217500 liters) and the amount of waste and emissions of gasoline vapors (7702356 liters per year), it can be concluded that the number of gasoline products consumed in 1397 in Tehran was about 4226919856 liters.