Environmental Engineering Reference
In-Depth Information
(4-30)
HCl
Cl
+H
(g)
(g)
OH+HCl
Cl
+H O
(4-31)
(g)
(g)
2
0
(4-32)
Hg
+2Cl
HgCl
(g)
(g)
2(g)
1
(4-33)
2HCl
2
O
Cl
H O
g
2 g
2 g
2
g
(4-34)
2Cl
Cl
(g)
2(g)
0
(4-35)
Hg
+Cl
HgCl
(g)
2(g)
2(g)
11.0
4
%
O
2
+ 1
3% CO
2
+83% N
2
+ 100 ppm HCl
10.0
Hg
0
(g)
Hg
2+
(g)
HgH
(g)
Hg(CH
3
)
2(g)
HgO
(g)
HgCl
(g)
HgCl
2(g)
HgCl
2(s)
8.0
×
6.0
4.0
2.0
0.0
-1.0
200
400
600
800
1000 1200 1400 1600 1800 2000
T
(K)
(a)
4% O
2
+13%CO
2
+83%N
2
100
0 10
-6
HCl
20 10
-6
HCl
40 10
-6
HCl
50 10
-6
HCl
100 10
-6
HCl
150 10
-6
HCl
500 10
-6
HCl
1000 10
-6
HCl
×
×
×
×
×
×
×
×
80
60
40
20
0
200
400
600
800
1000 1200 1400 1600 1800 2000
T
(K)
(b)
Fig. 4.66
Effect of HCl concentration on Hg transformation and reaction product
From Fig. 4.66, HCl had a significant impact on mercury oxidization. The more
the HCl content in the flue gas, the more HgCl
2
appeared. Possibly chlorine might
lead to Hg
0
oxidization by a homogeneous or heteogeneous, catalytic oxidization
process.
We introduce two parameters here: the initial temperature and cut-off tem-
perature of mercury. The initial temperature (
T
ts
) of mercury is defined as the
temperature point at which Hg
0
starts to transform to Hg
2+
. The cut-off temperature
(
T
te
), is the point at which Hg
0
converts into Hg
2+
completely. Fig. 4.67 shows the
Search WWH ::
Custom Search