Background:
In the operation of oil refineries, one of the main pollutants in stack emission is SO₂. Dispersion modeling is a necessary tool for simulation of air pollutant concentration, which is the main part of urban air quality management.
Objectives:
The ability of air quality models is well established where sufficient input data are available. The present study is performed to assess the SO₂ emission from the Tehran oil refinery.
Methods:
The release pattern of SO₂ was simulated by the AERMOD model in the desired zone, with an area of 25 × 25 km². Modeling was run in the 1, 3, 8, and 24 average times for two warm and cold seasons. Predicted and observed pollutant concentrations were compared for validation of the results by the EPA statistical index. Four receptors were selected to compare the predicted and observed values.
Results:
Correlation coefficient values for SO₂ were 0.92 and 0.95 for the warm and cold seasons, respectively. The maximum concentration of SO₂ was on the local scale of 25 × 25 km².
Conclusions:
The results showed that modeling is appropriate for conducting point sources in the oil refinery. 1 and 24 h averaging time from the model for SO₂ concentrations were lower than standard levels; therefore, in the study area, the AERMOD model performance for prediction of SO₂ concentrations was acceptable. Although most of the measurements were lower than standard values, due to the possibility of air pollution transmission to the urban area, their control should be considered.
Keywords:Air Pollutant Dispersion,Air Quality Model,AERMOD Model,OilRefinery Plant,SO2