Reformer monotube

SPARG tests in full -size monotube reformer ... 

Table 2.6 shows examples of combined steam and CO2 reforming demonstration in a full-size monotube pilot plant (Figure 3.6) or in industry [521]. The CO production per fired fuel (duty) in the reformer is compared. 

Table 2.6 CO2 reforming of natural gas. Demonstration tests in a full-size monotube reformer. Approximate duration 400 hours [521], Refer to Figure 2.18.

The Topsoe reforming technology was pioneered in a fiill-size monotube pilot plant during the 1960s as shown in Figure 3.2. The plant was running on naphtha. 

The sulphur passivated reforming was demonstrated in a series of tests in a full-size monotube reformer in Figure 3.6 [152]. Some of the tests are referred to in Figure 5.49 and Table 2.6 (Section 2.4.2). A t3T>ical temperature profile is shown in Figure 5.49 with a fast heat up of the gas to the reaction temperature for the sulphur passivated catalyst. 

Figure 5.49 Sulphur passivated reforming. Dibbem et al. [152], Axial temperature from full-size monotube pilot plant H2O/NG=0.96 mol/carbon. CO2/NG=0.64 mol/C-atom, P=7 bar abs. Reproduced with the permission of Gulf Publishing.

Figure 6. Measured and Calculated Axial and Radial Temperature Profiles. Topsoe Monotube Steam Reformer Pilot Data. Temperature approaches are shown for CH4-reforming (reaction (1)) and CH4-deposition (reaction (8)). If aT (1) > aT (8), there is not potential for carbon formation. This should be fulfilled at any position in the tube.

The retarding effect of sulphur is a dynamic phenomenon. This means that carbon may be formed at certain conditions in spite of sulphur passivation - although at strongly reduced rates and by a mechanism different from the formation of whisker carbon. Therefore, it was important to develop design criteria to make sure that the kinetic balance is in favour of no carbon formation at all positions in the reformer tube. This work was carried out mainly in the full-size monotube process demonstration plant (Dibbern et al., 1986). The influence of various process parameters (pressure, heat flux, sulphur content in feed, etc) was studied. It was demonstrated that the impact of variations in sulphur content in the feedstream on tube wall temperature and exit gas composition was completely reversible. 

TABLE 2. SPARG Tests in Full-size Monotube Reformer. 

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