1. Introduction - Firenze University Press

Temperature (°C)
8
7
6
5
4
3
2
1
0
16
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
Time (min)
79
Internal Temperature
Internal Pressure
Fig. 4. Pressure and temperature profile with elapsing time for CO2 hydrate formation in SDS 300
ppm- experimental run 2 in Table 1. Water spraying starts at t = 2 min.
In Fig. 5 pressure profiles for runs 1, 2, 3 in Table 1 are reported. These three runs help to determine
the effects of two different promoters (SDS and THF). It is evident that in absence of promoter,
pressure decreases, due to gas capture in the hydrate structure, are not observable. On the other
hand, in presence of promotor, pressure starts decreasing after 4-5 minutes, with an induction time
shorter than those observed in other experiments described in literature, as already proved in our
previous applications [20].
Pressure (bar)
32
31
30
29
28
27
26
no promotor
SDS 300 ppm
THF 1%wt
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
Time (min)
Fig. 5. Pressure profiles with elapsing time for CO2 hydrate formation with and without
promotors- experimental runs 1-2-3 in Table 1. Water spraying starts at t = 1 min.
Several samples were taken directly from the reactor. Hydrate storage capacity was determined
putting hydrate samples inside a custom-built dissociation vessel, as described in section 2.3.
32
30
28
26
24
22
20
18
Pressure (bar)