Sulfur dioxide emissions in Iran and environmental impacts of sulfur recovery plant in Tabriz Oil Refinery

Background: Combustion of fossil fuels contributes to sulfur dioxide (SO2) emissions. To deal with this issue, the government of Iran has appointed the oil refineries to upgrade their installations and produce high quality fuels. Thus, this study investigated the status of SO2 emissions in Iran and the capability of advanced technologies to control SO2 emissions. Methods: The status of SO2 emissions was reviewed and discussed through national online reports. Meanwhile, the environmental impacts of sulfur recovery and tail gas treatment (TGT) plant (STP) were assessed by applying rapid impact assessment matrix (RIAM) for implementation and nonimplementation alternatives in Tabriz Oil Refinery Company (TORC). Results: SO2 emissions have been increased by 2.1 times during 2004-2014 in Iran. Power plants and transportation play a significant role in this regard and overall contribute 82% of emissions. Among the other fossil fuels, fuel oil and gasoil account for 95% of SO2 emissions. Based on the environmental impact assessments (EIAs), sulfur recovery management and enhancing sulfur removal efficiency from flue gas up to 99.9% are two main positive environmental aspects of STP project that would enable TORC to prevent 87 600 tons of SO2 emissions, annually. Nevertheless, flue gas and sour gas streams which have been determined as probable pollution sources of process, should be managed through proper monitoring framework. Conclusion: The increasing trend of SO2 emissions and significant role of fuel oil and gasoil has required Iranian oil refineries to enhance the quality of fuels by employing clean and cost-effective technologies.