Influence of Mercury and Chlorine Content of Coal on Mercury Emissions from Coal-Fired Power Plants in China

Zhang, Lei; Wang, Yafei; Meng, Yonggang; Hao, Jiming

doi:10.1021/es300286n

Cited by 131 publications

(102 citation statements)

References 23 publications

(29 reference statements)

Supporting

Mentioning

100

Contrasting

Order By: Relevance

“…Simian were remarkably lower than that in Hg-mining areas (33-3638 ng·m −2 ·h −1 ) [28] and grassland (between 718 ± 1517 ng·m −2 ·h −1 and 4115 ± 1512 ng·m −2 ·h −1 ) [29] of Guiyang. The reason perhaps is due to human activities of production and livelihood, such as coal combustion and metallurgy, which contribute to elevated GEM concentrations in the Hg-polluted areas [2,23,30]. Comparing it with our previous research at Mt.…”

Section: Seasonal Dynamics Of Gem Fluxes At the Soil-air Interface Unmentioning

confidence: 76%

“…The GEM flux at the soil-air interface was minimum in winter, and the accumulation of atmospheric Hg in the forest soil at this time was remarkably more obvious than the other three seasons. On the other hand, Hg emission was weakened in winter, and the Hg deposited into the soil surface increased probably due to human activities such as coal combustion [23]. In early spring, the temperature began to increase.…”

Section: Seasonal Dynamics Of Gem Fluxes At the Soil-air Interface Unmentioning

confidence: 99%

See 1 more Smart Citation

A Two-Year Study on Mercury Fluxes from the Soil under Different Vegetation Cover in a Subtropical Region, South China

Sun

et al. 2018

Atmosphere

View full text Add to dashboard Cite

Abstract:In order to reveal the mercury (Hg) emission and exchange characteristics at the soil-air interface under different vegetation cover types, the evergreen broad-leaf forest, shrub forest, grass, and bare lands of Simian Mountain National Nature Reserve were selected as the sampling sites. The gaseous elementary mercury (GEM) fluxes at the soil-air interface under the four vegetation covers were continuously monitored for two years, and the effect of temperature and solar radiation on GEM fluxes were also investigated. Results showed that the GEM fluxes at the soil-air interface under different vegetation cover types had significant difference (p < 0.05). The bare land had the maximum GEM flux (15.32 ± 10.44 ng·m −2 ·h −1 ), followed by grass land (14.73 ± 18.84 ng·m −2 ·h −1 ), and shrub forest (12.83 ± 10.22 ng·m −2 ·h −1 ), and the evergreen broad-leaf forest had the lowest value (11.23 ± 11.13 ng·m −2 ·h −1 ). The GEM fluxes at the soil-air interface under different vegetation cover types showed similar regularity in seasonal variation, which mean that the GEM fluxes in summer were higher than that in winter. In addition, the GEM fluxes at the soil-air interface under the four vegetation covers in Mt. Simian had obvious diurnal variations.

show abstract

Section: Seasonal Dynamics Of Gem Fluxes At the Soil-air Interface Unmentioning

confidence: 76%

Section: Seasonal Dynamics Of Gem Fluxes At the Soil-air Interface Unmentioning

confidence: 99%

A Two-Year Study on Mercury Fluxes from the Soil under Different Vegetation Cover in a Subtropical Region, South China

Sun

et al. 2018

Atmosphere

View full text Add to dashboard Cite

show abstract

“…According to 30 previous on-site measurements in coalfired power plants and industrial boilers (Kellie et al, 2004;Duan et al, 2005;Lee et al, 2006;Zhou et al, 2006;Chen et al, 2007;Yang et al, 2007;Chen et al, 2008;Wang et al, 2008;Zhou et al, 2008;Kim et al, 2010b;Wang et al, 2010a;Zhang et al, 2012a;L. Zhang et al, 2013a), mercury speciation after the boiler and before APCDs is mainly determined by coal properties, specifically chlorine, mercury, and ash contents in coal.…”

Section: Zhang Et Al: Mercury Transformation and Speciation In Flmentioning

confidence: 99%

“…The charging anode of ESP can neutralize Hg 2+ and convert it to Hg 0 , while Hg 0 in flue gas continues to be oxidized to Hg 2+ via heterogeneous reactions in ESP under temperatures of 150-200 • C. Therefore, Hg 0 concentration can either increase or decrease inside ESP depending on the processes interplay. On-site measurements showed an average mercury removal efficiency of 29 % for ESP with a large range of 1-74 % (Goodarzi, 2004;Guo et al, 2004;Kellie et al, 2004;Tang, 2004;Duan et al, 2005;Lee et al, 2006;Chen et al, 2007;Yang et al, 2007;Wang et al, 2008;Zhou et al, 2008;Kim et al, 2010b;Shah et al, 2010;ICR, 2010;Wang et al, 2010a;Zhang et al, 2012a). Nevertheless, ESP installed after a CFB boiler can achieve an average of 74 % mercury removal due to the high Hg p proportion in flue gas (Chen et al, 2007;ICR, 2010;Zhang, 2012).…”

Section: Mercury Transformation In Electrostatic Precipitator (Esp)mentioning

confidence: 99%

“…Mercury speciation profiles in the flue gas from coal combustion are summarized in Table 1, which considers the transformation of mercury species across different types of APCDs (Goodarzi, 2004;Guo et al, 2004;Kellie et al, 2004;Tang, 2004;Duan et al, 2005;Lee et al, 2006;Zhou et al, 2006;Chen et al, 2007;Yang et al, 2007;Chen et al, 2008;Shah et al, 2008Shah et al, , 2010Wang et al, 2008;Zhou et al, 2008;Kim et al, 2010b;Wang et al, 2010a;Zhang, 2012;Zhang et al, 2012a;L. Zhang et al, 2013b).…”

Section: Mercury Speciation Profile For Coal-fired Boilersmentioning

confidence: 99%

See 1 more Smart Citation

Mercury transformation and speciation in flue gases from anthropogenic emission sources: a critical review

et al. 2016

Self Cite

View full text Add to dashboard Cite

Abstract. Mercury transformation mechanisms and speciation profiles are reviewed for mercury formed in and released from flue gases of coal-fired boilers, non-ferrous metal smelters, cement plants, iron and steel plants, waste incinerators, biomass burning and so on. Mercury in coal, ores, and other raw materials is released to flue gases in the form of Hg 0 during combustion or smelting in boilers, kilns or furnaces. Decreasing temperature from over 800 • C to below 300 • C in flue gases leaving boilers, kilns or furnaces promotes homogeneous and heterogeneous oxidation of Hg 0 to gaseous divalent mercury (Hg 2+ ), with a portion of Hg 2+ adsorbed onto fly ash to form particulate-bound mercury (Hg p ). Halogen is the primary oxidizer for Hg 0 in flue gases, and active components (e.g., TiO 2 , Fe 2 O 3 , etc.) on fly ash promote heterogeneous oxidation and adsorption processes. In addition to mercury removal, mercury transformation also occurs when passing through air pollution control devices (APCDs), affecting the mercury speciation in flue gases. In coal-fired power plants, selective catalytic reduction (SCR) system promotes mercury oxidation by 34-85 %, electrostatic precipitator (ESP) and fabric filter (FF) remove over 99 % of Hg p , and wet flue gas desulfurization system (WFGD) captures 60-95 % of Hg 2+ . In non-ferrous metal smelters, most Hg 0 is converted to Hg 2+ and removed in acid plants (APs). For cement clinker production, mercury cycling and operational conditions promote heterogeneous mercury oxidation and adsorption. The mercury speciation profiles in flue gases emitted to the atmosphere are determined by transformation mechanisms and mercury removal efficiencies by various APCDs. For all the sectors reviewed in this study, Hg p accounts for less than 5 % in flue gases. In China, mercury emission has a higher Hg 0 fraction (66-82 % of total mercury) in flue gases from coal combustion, in contrast to a greater Hg 2+ fraction (29-90 %) from non-ferrous metal smelting, cement and iron and/or steel production. The higher Hg 2+ fractions shown here than previous estimates may imply stronger local environmental impacts than previously thought, caused by mercury emissions in East Asia. Future research should focus on determining mercury speciation in flue gases from iron and steel plants, waste incineration and biomass burning, and on elucidating the mechanisms of mercury oxidation and adsorption in flue gases.

show abstract

Regression modeling of gas-particle partitioning of atmospheric oxidized mercury from temperature data

Cheng

Zhang

Blanchard

2014

J. Geophys. Res. Atmos.

View full text Add to dashboard Cite

Models describing the partitioning of atmospheric oxidized mercury (Hg(II)) between the gas and fine particulate phases were developed as a function of temperature. The models were derived from regression analysis of the gas-particle partitioning parameters, defined by a partition coefficient (K p ) and Hg(II) fraction in fine particles (f PBM ) and temperature data from 10 North American sites. The generalized model, log(1/K p ) = 12.69-3485.30(1/T) (R 2 = 0.55; root-mean-square error (RMSE) of 1.06 m 3 /μg for K p ), predicted the observed average K p at 7 of the 10 sites. Discrepancies between the predicted and observed average K p were found at the sites impacted by large Hg sources because the model had not accounted for the different mercury speciation profile and aerosol compositions of different sources. Site-specific equations were also generated from average K p and f PBM corresponding to temperature interval data. The site-specific models were more accurate than the generalized K p model at predicting the observations at 9 of the 10 sites as indicated by RMSE of 0.22-0.5 m 3 /μg for K p and 0.03-0.08 for f PBM . Both models reproduced the observed monthly average values, except for a peak in Hg(II) partitioning observed during summer at two locations. Weak correlations between the site-specific model K p or f PBM and observations suggest the role of aerosol composition, aerosol water content, and relative humidity factors on Hg(II) partitioning. The use of local temperature data to parameterize Hg(II) partitioning in the proposed models potentially improves the estimation of mercury cycling in chemical transport models and elsewhere.

show abstract

Influence of Mercury and Chlorine Content of Coal on Mercury Emissions from Coal-Fired Power Plants in China

Cited by 131 publications

References 23 publications

A Two-Year Study on Mercury Fluxes from the Soil under Different Vegetation Cover in a Subtropical Region, South China

A Two-Year Study on Mercury Fluxes from the Soil under Different Vegetation Cover in a Subtropical Region, South China

Mercury transformation and speciation in flue gases from anthropogenic emission sources: a critical review

Regression modeling of gas-particle partitioning of atmospheric oxidized mercury from temperature data

Contact Info

Product

Resources

About