Bachgrounds and Objectives: Oil, gas and petrochemical are known as important sources of air pollutants and emission of green house gases. About 99 percent of sulfur dioxide in the air is produced from human resources. Although several samples have been taken from industries and refineries' output by environmental experts and private companies, but accurate assessment is not available based on pollutant emissions on product levels (emission coefficients) and on the total amount of the annual emission which, can be used as basic modeling of air pollution and planning.
Materials and Methods: This study was cross sectional and the output of the chimney measured with Testo 350 XL system. Performance standard was determined based on ASTM D6522 EPACTMO30-41. The amounts of sulfur dioxide were measured from Tehran oil refinery's outlet from the beginning of the march 2007 till the year 2008 for 20 months. Sampling was carried out on averaged range (9 am to 14 pm).
Results: The results showed that Northern Distillation unit produced pollutants' concentration more than 3 times in the southern Distillation unit. An emission of pollutants from Northern unit was, 2.8 times higher than the Southern unit. The northern emission factor was 5.6 times higher than the value obtained from southern unit. The Concentration, emissions and coefficient of sulfur dioxide in North catalyst convert unit were more than 2 times in comparison with the same South unit. These three factors in northern concentration breakers unit were 3, 2.6 and 2.6 times higher than the Southern concentration breakers unit‚ respectively.
Discussion: Emission rate in all northern units is 2 to 3 times more than similar southern units. The production volumes in northern units are higher than the southern units and the southern units designed properly to remove more pollutants .The use of new technologies in production processes and application of the latest scientific resources can play a major role on pollutants' reduction.