Mercury from combustion sources: A review of the chemical species emitted and their transport in the atmosphere

Mercury risk from fluorescent lamps in China: Current status and future perspective

“…Thermal power generation is based almost exclusively on coal combustion, which represents half of the country's coal consumption. Mercury, which is a natural constituent of coal, is released upon combustion of the coal (Carpi, 1997). Raw coals from China contain about 0.02 to 0.52 g (average: 0.19 g) of mercury per tonne, while coal cleaning can remove, on average, 30% of the mercury (Streets et al, 2005).…”

“…Emissions of mercury from coal-fired plants are 20-50% elemental mercury (Hg 0 ) and 50-80% oxidized mercury (Hg(II)), with little mercury in the particulate form (Carpi, 1997), although the physical and chemical forms of the mercury emitted may vary significantly depending on the types of coal being combusted and APCD installed. Oxidized mercury and particulate mercury bound to particles have relatively short atmospheric lifetimes (up to approximately 2 weeks), and undergo wet and dry deposition regional to the point of emission (Carpi, 1997, Schroeder andMunthe, 1998;Seigneur et al, 2004).…”

“…Elemental mercury is predominantly present in gaseous and vapor phases, and accounts for 95% of atmospheric mercury in general (Nriagu, 1989;Schroeder and Munthe, 1998). It has a long atmospheric residence time in the order of 6-24 months and is eventually removed by wet deposition after being photo-oxidized to water soluble Hg(II) species and by dry deposition (Carpi, 1997;Schroeder and Munthe, 1998). It should be noted that significant interconversion between mercury species can occur in the atmosphere (e.g., oxidation of elemental mercury and reduction of oxidized mercury), which further complicates their transport and fate (Lin et al, 2006(Lin et al, , 2007.…”

“…It should be noted that significant interconversion between mercury species can occur in the atmosphere (e.g., oxidation of elemental mercury and reduction of oxidized mercury), which further complicates their transport and fate (Lin et al, 2006(Lin et al, , 2007. The distribution of elemental mercury is influenced by atmospheric circulations on the local, regional and global scales (Carpi, 1997;Lin and Pehkonen, 1999;Loewen et al, 2005;Schroeder and Munthe, 1998). Therefore, excessive mercury emissions from power plants can increase regional and even global mercury levels in the air.…”

“…Because mercury and its compounds are volatile, up to 90% of the mercury in fluorescent lamps may be released directly into the air upon incineration in the absence of mercury emission controls (USEPA, 1998). The amount of mercury released into the air could be significantly reduced by flue gas cleaning, although elemental mercury is much more difficult to capture than oxidized and particulate mercury (Carpi, 1997;Pavlish et al, 2003). Advanced MSW incinerators equipped with dry/semi-dry scrubbing, activated carbon injection and fabric bag filter systems in China could remove 60-100% of the mercury from the flue gas (Wu, 2009;Zhang et al, 2008).…”