Trend and characteristics of atmospheric emissions of Hg, As, and Se from coal combustion in China, 1980–2007

Abstract

Abstract. Emissions of hazardous trace elements in China are of great concern because of their negative impacts on local air quality as well as on regional environmental health and ecosystem risks. In this paper, the atmospheric emissions of mercury (Hg), arsenic (As), and selenium (Se) from coal combustion in China for the period 1980-2007 are estimated on the basis of coal consumption data and emission factors, which are specified by different categories of combustion facilities, coal types, and the equipped air pollution control devices configuration (Dust collectors, FGD, etc.). Specifically, multi-year emission inventories of Hg, As, and Se from 30 provinces and 4 economic sectors (thermal power, industry, residential use, and others) are evaluated and analyzed in detail. Furthermore, the gridded distribution of provincialbased Hg, As, and Se emissions in 2005 at a resolution of 1 • × 1 • is also plotted. It shows that the calculated national total atmospheric emissions of Hg, As, and Se from coal combustion have rapidly increased from 73.59 t, 635.57 t, and 639.69 t in 1980 to 305.95 t, 2205.50 t, and 2352.97 t in 2007, at an annually averaged growth rate of 5.4%, 4.7%, and 4.9%, respectively. The industrial sector is the largest source for Hg, As, and Se, accounting for about 50.8%, 61.2%, and 56.2% of the national totals, respectively. The share of power plants is 43.3% for mercury, 24.9% for arsenic, and 33.4% for selenium, respectively. Also, it shows remarkably different regional contribution characteristics of these 3 types of trace elements, the top 5 provinces with the heaviest mercury emissions in 2007 are Shandong (34.40 t), Henan (33.63 t), Shanxi (21.14 t), Guizhou (19.48 t), and Hebei (19.35 , provinces always rank at the top five largest Hg, As, and Se emission sources are: Shandong, Hebei, Shanxi, Henan, and Jiangsu, most of which are located in the east and are traditional industry-based or economically energy intensive areas in China. Notably, Hg, As, and Se emissions from coal combustion in China begin to grow at a more moderate pace since 2005. Emissions from coal-fired power plants sector began to decrease though the coal use had been increasing steadily, which can be mainly attributed to the increasing use of wet flue gas desulfurization (WFGD) in power plants, thus the further research and control orientations of importance for these hazardous trace elements should be the industrial sector.

Atmospheric emission inventory of cadmium from anthropogenic sources

“…The statistical data of coal consumption and detailed emission factors are adopted to calculate the atmospheric emissions of Cd from coal burning. In this study, the methodologies for determining the average content of Cd in coals as produced and consumed at provincial levels are consistent with the previous detailed analysis, the detail algorithms for determining Cd content in coals as consumed, cleaned coals, coal briquettes, and cokes as produced can be referred to the previous studies (Tian et al 2010(Tian et al , 2011(Tian et al , 2012a. The data sources and final Cd content in coal products as consumed are listed in Table S1-S4 of the Supplemental Information (SI).…”

“…By now, the understanding on the situation of anthropogenic atmospheric emissions of Cd in China is quite limited compared with some other trace elements such as mercury and antimony, and there have been few published estimates to date of Cd emissions in China (Tian et al 2010(Tian et al , 2012a. The development of a complete emission inventory is an important step in an air quality management process.…”

Seasonal Variations and Sources of 17 Aerosol Metal Elements in Suburban Nanjing, China

“…Sb, Se and Sr are commonly used as markers of coal burning emissions [29]. In addition to coal burning, As can be also emitted by iron making and steelmaking processes [69]. As shown in Figure 6, the contributions of coal burning factor were significantly high in autumn (31.49%) and winter (35.07%), in accordance with the enhanced coal consumption for energy supply during the cold seasons.…”

Updated atmospheric speciated mercury emissions from iron and steel production in China during 2000–2015

“…However, the Hg concentration data from limited samples may lead to large uncertainty in the national inventory. Many studies have reported Hg concentrations in coal (Swaine, 1992;Tian et al, 2010;USGS, 2004;Zhang et al, 2012). But the specific requirement of low-sulfide coal (less than 1.2 %) in ISP may lead to different Hg concentrations in the consumed coal (Tao and Wang, 1994) since low-sulfide coal was generally accompanied by low Hg (Zhang, 2012).…”