Now, you want to decrease the methane slip to a new target of 6.0 v% methane.
You can increase steam/carbon ratio or you can change temperature. Suppose you
chose to change temperature. In the upper chart, find where 3.0 steam/carbon
crosses the 6.0 % methane slip line. Then, follow the index line vertically
down to the 300 psig on the lower chart. The indicated equilibrium temperature is
about 1,500
F. So, increasing the reformer outlet temperature by 1,500
FÀ1,465
F
= +35
F should bring the methane slip to 6.0 v%.
100
Pressure, psig
200
600
300
400
500
Temperature, °F
0
2
4
6
8
10
12
14
16
18
Equilibrium % CO in Dry Gas
Steam/Carbon Ratio
Fig. 8 CO slip equilibrium chart for steam/methane reforming of methane (After: Katalco 1970)
Hydrogen Production and Management for Petroleum Processing
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