Controlling Pollutants in Coal-Fired Power Plants in China - Mercury Emission and its Control in Chinese Coal-Fired Power Plants - page 4

1.3 Research of Mercury Emissions and Their Control in China
1.3.1 Mercury Emissions in China
According to the UNEP report released in 2008, China, the United States and India
are the three countries with the largest mercury emissions, with an aggregate rate of
about 57% of total global emissions. It is said that by 2008, mercury emissions in
China were twice those of the United States and India combined, with nearly 50%
of mercury emissions coming from the burning of fossil fuels in China.
Some reports show that in China average mercury concentration in coal is 0.22
mg/kg, which is more than 0.13 mg/kg of the world average. Many scholars used
different methods to estimate mercury emissions from coal-fired plants in China.
Feng et al . [10] estimated mercury emissions in the atmosphere to be 296 tons; if the
present pollution control facilities are maintained, the annual amount of mercury
emissions can increase by 5.3%. Wang et al . [11] studied the mercury concentration in
Chinese coal and the emissions of mercury from coal-fired industries and estimated
the mercury emissions in the atmosphere in China in 1995 to be about 213.8 tons.
Mercury emissions from coal-fired industries reached 2493.8 tons in the years
1978-1995, with emissions growing at an average annual rate of 4.8%. David and
Streets et al . [12] analyzed the national statistical yearbook data for 1999 and esti-
mated the mercury emissions to be 536(±236) tons, 38% of which came from
coal-fired industries. Meanwhile, Jiang et al . [13] divided mercury emission sources
into 65 various types according to the following criteria: economic sector, flue type,
method of burning and pollutant emission control technology. They established a
mercury emission inventory of coal-fired industries in the provinces according to
coal consumption, mercury concentration in coal and the mercury emission factor in
China. The two sets of data released by the US Geological Survey (USGS) showed
that the average mercury concentration in Chinese coal was 0.15 and 0.20 mg/kg,
respectively. Both were higher than the global average mercury concentration of
0.13 mg/kg. In addition, the two data sets also indicated Hg (g) emissions from
coal-fired industries in 2000 at 161.6 and 219.5 tons, respectively. At present, about
35% of total mercury comes from electric power industries. China has an unequal
distribution of mercury emissions from coal-fired industries, and provinces with
major emissions include Henan, Shandong, Guizhou, Guangdong and Jiangsu.
Ren et al . [14] reported that the average annual growth rate of Hg (g) emissions
coming from the coal-fired power plants in China from 1999 to 2003 was 9.59%
and that for non-Hg (g) emissions was 8.49%. There were 86.8 and 28.94 tons of
Hg (g) and non-Hg (g) emissions, respectively, from coal-fired power plants in 2003.
Wang et al . [15] estimated that the mercury emission was about 256 tons from the
coal-fired industry in 2003. According to actual test data of coal-fired power plants,
Hu et al . [3] estimated the total mercury emissions from coal-fired power plants in
2005 to be 193.6 tons, including 147.0 tons of Hg (g) .