Environmental Engineering Reference
In-Depth Information
24
1st
2nd
3rd
22
YK-AC_Hg
0
YK-AC_Hg
2+
XK-AC_Hg
0
XK-AC_Hg
2+
MZ(sm)-AC_Hg
0
MZ(sm)-AC_Hg
2+
20
18
16
14
12
10
8
6
4
2
0
0:02:20
0:04:50
0:07:20
0:09:50
0:12:20
0:14:50
0:17:20
0:19:50
0:22:20
0:24:50
0:27:20
0:29:50
Fig. 5.23
Hg
0
adsorption by ACs in simulated flue gas environment
the second phase. In the fourth phase, the simulated flue gas components were
turned off one by one as follows: H
2
O/HCl, NO, NO
2
, SO
2
, O
2
, and CO
2
.
In the process of changing the gas components, the total simulated flue gas flow
was maintained at 1266 ml/min. The influence of the simulated flue gas compo-
nents on mercury speciation is shown in Fig. 5.24. The horizontal axis showed the
experiment time in h:m:s. There were four ordinate axes, namely, A, B, C, and D.
The A axis showed the mercury concentration in simulated flue gas in g/(Nm
3
);
the B axis showed the O
2
and CO
2
concentrations in simulated flue gas as a per-
centage; the C axis showed the NO and NO
2
concentration in simulated flue gas in
ppm; and the D axis showed the SO
2
concentration in simulated flue gas in ppm.
The water and HCl concentrations were adjusted to 10% and 50 ppm, respectively,
based on standard gas.
Time (h:m:s)
.
Axis A: mg/(N m
3
) B: %
Axis C: ppm, D: ppm
18
3500
1st
2nd
3rd
4th
16
300
3000
8
14
250
2500
12
6
200
2000
10
Hg
0
(A: mg/(N m
3
))
Hg
2+
NO (C: ppm)
NO
2
(C: ppm)
SO
2
(D: ppm)
O
2
(B: %)
CO
2
(B:
%
)
.
.
(A: mg/(N m
3
))
8
150
1500
4
6
100
1000
4
2
50
500
2
0
0
0:13:10
0:26:30
0:39:50
0:53:10
1:06:30
1:19:50
1:33:10
1:46:30
Time (h:m:s)
Fig. 5.24
Influence of simulating flue gas components on mercury speciation
Approximately 14% of Hg
0
was oxidized to Hg
2+
with the action of the simu-
lated flue gas components (Fig. 5.24). However, AC had a good adsorption capa-
bility for Hg
0
(the initial adsorption efficiency was about 80%, as shown in
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