Evaluation of mercury emissions from the first coal-fired power plant in Iran using atmospheric dispersion modeling

Iran plans to build the first coal-fired power plant in 2025 as part of its electricity generation development program. Coal-fired power plants are the main anthropogenic source of mercury emissions. According to Article 8 of the Minamata Convention on Mercury, all Parties need to set targets to control mercury emissions from these sources. No studies have been carried out to estimate mercury emissions from future development plans for coal-fired power plants in Iran. Therefore, the main objectives of this research are to estimate mercury emissions from this power plant and evaluate the best available technologies to control mercury emissions. In the first step, to achieve these objectives, mercury emissions under 13 scenarios were estimated based on the interactive process optimization guidance model and experimental data. To predict ground-level mercury concentrations in the second step, a Gaussian atmosphere dispersion model coupled with a mesoscale numerical weather prediction model was applied. Finally, the hazard quotient was used to assess inhalation risks. The results show that hourly mercury emissions, mercury concentration, and mercury emission factor are estimated to be 0.672 g/h, 0.2 μg/Nm³, and 0.45 kg/TWh, respectively, when circulating fluidized bed boilers equipped with the in-furnace desulfurization process and the cold-side electrostatic precipitator unit are utilized as the best available technology for mercury emission control. In conclusion, the hazard quotient indicates that ground-level mercury concentrations are improbable to induce inhalation risks for the community living within a 30 km radius from this power plant.