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concentration was about 30% higher under conditions 3 and 4. In the mixed com-
bustion of QP-S coal and HB-B coal, the oxidation of Hg 0 in the flue gas was a little
higher than that in the mixed combustion of CF-S coal and 2 # -B coal, indicating a
possible relationship to the types of coal.
70
Hg 0
60
(g)
Hg 2+
(g)
50
40
30
20
10
0
No.1
No.2
Fig. 4.9 Ratio of Hg 0 and Hg 2+ in No. 1 and No. 2 conditions
80
70
Hg 0 (g)
Hg 2+ (g)
60
50
40
30
20
10
0
No.3
No.4
Fig. 4.10 Ratio of Hg 0 and Hg 2+ in No. 3 and No. 4 conditions
The ratios of Hg (g) and Hg p in different conditions are shown in Fig. 4.11 and
Fig. 4.12, respectively. The mercury in the flue gas had two gaseous forms (Hg 2+
and Hg 0 ) and Hg p . The latter was the mercury in the fly-ash particles. The concen-
trations of Hg (g) and Hg p were in the flue gas in a gas-solid two-phase. The ratio of
Hg (g) in the total mercury ranged from 46% to 75%, whereas Hg p in fly ash particles
took up 59% - 70%. Overall, in No. 1 and No. 3 conditions, without limestone, the
Hg (g) in the flue gas had a higher ratio at 68% and 75%, respectively; however, the
proportion of Hg p was lower. In No. 2 and No. 4 conditions, with limestone, the
 
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