Civil Engineering Reference
In-Depth Information
120
t
= 150 min
m
Al
= 0.067 g
100
80
60
m
Al
= 0.021 g
40
v
c
m
Al
= 0 g
20
v
(t)
0
0
50
100
150
200
250
300
Time (min)
12.16
Rate of hydrogen liberation due to alkaline hydrolysis with
aluminium in MSWI fly ash. After Aubert et al. (2004).
110
Calculated curve (relation (3))
Experimental points zone
90
70
50
30
10
0.000
0.010
0.020
0.030
0.040
0.050
0.060
0.070
0.080
-10
Mass of aluminum (g)
12.17
Comparison of predicted and measured quantities of hydrogen
liberated during alkaline hydrolysis with aluminium in MSWI ash.
After Aubert et al. (2004).
(< 125 mm) MSWI ashes, through reaction with sodium hydroxide and
measurement of the volume of hydrogen liberated, which has been adopted
elsewhere (Qiao et al. 2008b; see Fig. 12.18). They found rapid gas evolution
in the first 50 minutes of reaction, after which the rate was reduced, the test
yielding quantitive results after a few hours. Their final recommendation
was to operate the test for 150 minutes and propose a means for estimation
of the total free aluminium content of the ash. This pragmatic approach has
