Mercury emissions of a coal-fired power plant in Germany

Abstract

Abstract. Hg / SO 2 , Hg / CO, NO x / SO 2 (NO x being the sum of NO and NO 2 ) emission ratios (ERs) in the plume of the coal-fired power plant (CFPP), Lippendorf, near Leipzig, Germany, were determined within the European Tropospheric Mercury Experiment (ETMEP) aircraft campaign in August 2013. The gaseous oxidized mercury (GOM) fraction of mercury emissions was also assessed. Measured Hg / SO 2 and Hg / CO ERs were within the measurement uncertainties consistent with the ratios calculated from annual emissions in 2013 reported by the CFPP operator, while the NO x / SO 2 ER was somewhat lower. The GOM fraction of total mercury emissions, estimated using three independent methods, was below ∼ 25 %. This result is consistent with other findings and suggests that GOM fractions of ∼ 40 % of CFPP mercury emissions in current emission inventories are overestimated.

Mercury distribution in the upper troposphere and lowermost stratosphere according to measurements by the IAGOS-CARIBIC observatory: 2014–2016

“…At ∼ 30 km altitude GEM could be oxidized by Br atoms released by the photolysis of halons and/or by reactions with O atoms (Ko et al, 2013). Collocation of stratospheric loss regions of COS and GEM supports the hypothesis of close relation of stratospheric mercury to stratospheric sulfur (COS + sulfate particles) described by Wilson et al (2008). The obvious implication of the long stratospheric TM and GEM lifetimes is that most atmospheric mercury is oxidized in the troposphere.…”

“…A reduction of TM concentration from ∼ 1.2 ng m −3 in tropospheric air to ∼ 0.66 ng m −3 in stratospheric air is too large to be explained by the aerosol bias induced by the incomplete particle sampling mentioned above and requires the presence of an Hg 2+ removal process. As already proposed by Lyman and Jaffe (2012) such a removal process requires the oxidation of GEM into Hg 2+ , followed by attachment of Hg 2+ to stratospheric (mainly sulfate) particles, and their removal by gravitational sedimentation and/or scavenging by clouds (Menzies and Tratt, 1995;Rasch et al, 2008;Wilson et al, 2008). We note that air mass exchange is also taking an important part in removing sulfate particles from the stratosphere but TM concentrations would not change without sedimentation and/or scavenging of Hg 2+ on particles.…”

Multi-model study of mercury dispersion in the atmosphere: vertical and interhemispheric distribution of mercury species

“…Both Tekran instruments were run with upstream particle filters and one additionally with a quartz wool trap, which presumably removes GOM (Lyman and Jaffe, 2012;Ambrose et al, 2013). Neglecting PBM, the concentration of which is usually negligible, the measurement by Tekran without the quartz wool trap approximates TM and that with quartz wool trap GEM (Weigelt et al, 2016b). GEM was also measured by a modified Lumex instrument (Weigelt et al, 2016b).…”

“…Neglecting PBM, the concentration of which is usually negligible, the measurement by Tekran without the quartz wool trap approximates TM and that with quartz wool trap GEM (Weigelt et al, 2016b). GEM was also measured by a modified Lumex instrument (Weigelt et al, 2016b). Additionally, GOM was collected on denuders and analyzed on return to the laboratory.…”

response to Ian Hedgecock review

“…This reflects in part our dependence of Hg II reduction on OA concentrations, which are particularly high in China (Heald et al, 2011). Decreasing wet deposition in this region in the model has implications for the long-range transport of atmospheric Hg from East Asia (Weiss-Penzias et al, 2007). Figure 7 shows the global distribution of wet and dry Hg II deposition in the model.…”