Modelling of the atmospheric dispersion of mercury emitted from the power sector in Poland

Poland belongs to the group of EU countries with the highest levels of mercury emissions, with a large portion of these emissions being related to coal combustion. This paper presents a modelling analysis of the impact that the Polish power sector has on the atmospheric concentrations of mercury. A detailed mercury emission inventory is used to analyse the concentration and deposition of mercury. For this study, a chemical scheme devoted to mercury transformations in the atmosphere was implemented into the Polyphemus air quality system. The system was then used to perform simulations for 2008 in two domains i.e. over Europe and over Poland. The impact of various parameters on concentration and wet scavenging of mercury has been analysed. The results of the mercury ambient concentrations and depositions, are presented. Additionally, the contribution of natural and anthropogenic sources to mercury deposition in Poland is shown. The performed works showed that the national sources have low impact to overall deposition, however local contribution in wet deposition of big emitters may reach 50%. Sensitive analysis showed a significant impact of reaction with bromine compound and scavenging coefficient on modelled results of mercury concentration and deposition.