Dispersion of SO2 emissions in a gas refinery by AERMOD modeling and human health risk: a case study in the Middle East.

This study aimed to model the dispersion of emitted SO2 from stacks and flares in one of the largest Gas Refinery Companies in the Middle East . Pollutant emission coefficients and air pollution's various sources contributions were determined based on the collected data after measuring SO2 concentrations in a fixed monitoring station (stack) and across different distances from it for a year. The SO2 release pattern was simulated, and annual pollutant concentrations in average periods of 1-hr and 24-hr were predicted using AERMOD 8.9.0. The maximum simulated ambient SO2 were 27,447 and 4592 µg/m3 in average sampling times of 1-hr and 24-hr, respectively. The hazard quotient of 95% percentile for children, teenagers, and adults due to inhalation of SO2 was more than one.The maximum concentration of SO2 in the 1-hour and 24-hour period in the study area was higher than the amount introduced by Iran's clean air standard and the WHO standard.

Assessment of air quality using AERMOD modeling: a case study in the Middle East.

Emissions of greenhouse gases from industrial facilities, such as refineries, are one of the most significant environmental problems in many countries. This study aimed to assess the present status of emission sources near a gas refinery region, and the contribution of sources to air pollution was estimated by monitoring CO for a year at a fixed station. This descriptive-analytical study was conducted between January and December 2020. A simulation of CO gas distribution and pollutant concentration prediction was carried out. The results show that the maximum concentration of CO in the 1-h period was 2260 µg/m3, which corresponds to the peak concentration in spring, and in the 8-h period, it was 573 µg/m3, which corresponds to the peak concentration in winter. The studied area's maximum pollutant concentration was also compared to national and international standards for clean air. In all four seasons, the maximum simulated CO concentrations were lower than the Iranian and EPA standards for clean air. Maximum concentrations have occurred in the southern slopes of the study area's heights, and, due to the appropriate wind speed, maximum concentrations in the northeastern mountain peaks occurred at a more considerable distance due to the high altitude of the mountains and the lack of suitable conditions for pollutant escape. Furthermore, because of the height of smokestacks and flares from the ground and the effect of wind on the release height, the concentration of pollutants at the foot of the stacks is low and decreases gradually over a certain distance. Finally, the distribution and deposition of pollutants in the pathway of the smoke were influenced by the type of topography.

Carbon footprint calculation in one of the largest Gas Refinery Companies in the Middle East.

Rapid technological advances in the natural gas industry raised access to natural gas reserves, related to increased greenhouse gas emissions, including CO2 and CH4. This study calculates greenhouse gas emissions (CO2 and CH4) according to sources (direct and indirect) in one of the largest gas Refinery Companies in the Middle East to analyze the carbon footprint for the first time. All computational frameworks for estimating carbon footprint and greenhouse gas emissions (CO2 and CH4) in different sectors were carried out after determining direct sources (combustion, processes, and fugitive) and indirect ones (import from National Grid's electricity) according to the requirement guide and organizations' report involved in the operational activities of the oil industry. The carbon footprint for this refinery, leading to the emission of CO2 and CH4, is in the range of 1507.1 Gg CO2/yr and 0.003 Gg CH4/yr. The highest CO2 emissions are related to the gas-sweetening unit from GHG direct emission sources, and the lowest CO2 emissions are related to fugitive ones. For methane gas, the highest CH4 emissions are related to fugitive emissions. In addition, the emission of CH4 from the gas sweetening unit and waste combustion equipment is estimated to be very small and close to zero. This study showed that it is necessary to carry out more studies in different regions to give a more comprehensive insight into gas emissions and their adverse health effects on human populations.