Reformer composition

C, 0.356—1.069 m H2/L (2000—6000 fU/bbl) of Hquid feed, and a space velocity (wt feed per wt catalyst) of 1—5 h. Operation of reformers at low pressure, high temperature, and low hydrogen recycle rates favors the kinetics and the thermodynamics for aromatics production and reduces operating costs. However, all three of these factors, which tend to increase coking, increase the deactivation rate of the catalyst therefore, operating conditions are a compromise. More detailed treatment of the catalysis and chemistry of catalytic reforming is available (33—35). Typical reformate compositions are shown in Table 6. 

Example 10-8 Methane Reforming - Determine the Reformate Composition... 

Thermodynamics. - The thermodynamics of ATR have been reviewed by a number of researchers.Collectively, these papers provide guidance on the optimal operating temperature and the effects of steam and air concentrations on reformate composition. The effects of pressure on H2... 

Fig. 18. Reforming composition profiles for C6 system at 794 K, 2620 kPa, with MCP hexane feed (data A, benzene P, hexane C, C5).

Fig. 21. Reforming composition profiles for C6 system during deactivation.

Fig. 27. Isothermal reforming composition profiles, at 782 K, 2620 kPa, C6- 461 K Arab Light.

For commercial simulations, KINPTR s selectivity kinetics determine the reformate composition and overall yield at a target reformate octane. Reformer yield-octane behavior from pilot and commercial units are shown in Fig. 29a. The large variation in the reformate yields at a given octane, as much as 25%, results from the wide range of process conditions and naphtha feed quality used in Mobil reformers. As demonstrated in Fig. 29b, KINPTR accurately normalizes these reformate yields over a wide range of octanes, including those required for gasoline lead phaseout. 

Table 2.9 Conversion, power density, reaction temperature and reformate composition for various fuels [131].

Unlike PSAs and membranes, FI MH systems are projected to have very similar purification cost regardless of reformate composition, making them particularly suitable for ATR and renewable-based hydrogen production. 

Measure fuel processor operation and reformate composition over long operational period (1000 hrs)... 

A kinetic model for the naphtha catalytic reforming process, which utilizes lumped mathematical representation of the reactions that take place, is presented. The reaction are written in terms of isomers of the same nature, which range from 1 to 11 atoms of carbon for paraffins, and from 6 to 11 carbon atoms for naphthenes and aromatics. The kinetic parameters values were estimated using experimental information obtained in a fixed-bed pilot plant. The pilot reactor was loaded with different amounts of catalyst in order to simulate a series of three reforming reactors. The reformate composition calculated with the proposed model agrees very well with experimental information. 

Figure 1. Experimental (points) and calculated (lines) reformate composition at S10 C 5. CONCLUSIONS...

The proposed kinetic model has twenty four differential equation with seventy one kinetic parameters, which were estimated using experimental information obtained in a fixed-bed pilot plant. The calculated reformate composition agrees very well with experimental data with average deviation less than 3%. 

The reformate composition that enters the anode compartment of the PEMFC stack is dependent on the hydrocarbon feed. For natural gas feed, the typical reformate composition is, in mol% H2 50%, CH4 <1%, H2O 1.5%, CO2 15 %, N2 32% (for Dutch natural gas), CO < 10 ppm (ECN, internal communication. The CO content in the reformate is the most critical parameter, because the anode catalyst in the PEMFC, a Pt-based catalyst, will be poisoned by CO. 

E. C. N.Van Den Oosterkamp, internal communication stationary PEMFC system and reformate composition, 2004,... 

Figure 3 shows the equilibrium reformate composition at different temperatures based on stationary process flow sheet simulations (ChemCAD ). The flow rate ratio of AOG to propane has been kept constant at a calculated (0/C)Ref of 1.82. Hydrocarbon conversion is almost complete for reforming temperatures above 700 C. The fraction of H2 and CO is greater than 60 Vol.-%. Soot formation is inhibited above 720 °C for the distinct operation conditions. 

Figure 3. Reformate composition for combined steam-/dry-reforming of propane at different equilibrium temperatures, (0/C)Ref= 1.82...

The Staxera ISM contains two Mk200 stacks with 30 ESC4" -celIs each. The stack was characterized in a controlled furnace environment prior to the system development to understand its performance at AOG reformate operation. ZBT conducted thermodynamic simulations of reformate composition for different fuel compositions depending on recycle-ratio, fuel utilizations of the SOFC stack, AOG recycle rates and reformer temperatures. Corresponding gas mixtures were fed to an Mk200/ESC4 stack and power output and fuel utilization as characteristic performance values were experimentally determined. The test results for 19 different fuel gas compositions and flow rates are shown in Figure 3. 

Figure 3.10 Dry reformate composition during isooctane partial oxidation in the presence of steam S/C = 3.0 0/C= 1.0 ...

Figure 3.34 C-H-O phase diagram for a mixture of 75 vol.% hydrogen, 15 vol.% carbon monoxide, the balance being carbon dioxide the boundary for carbon deposition is indicated by the straight line (o) composition of natural gas reformate ) composition of water-free natural gas reformate [120],...

Number of carbon atoms of the alkane feed molecule Figure 5.15 Reformate composition versus carbon number of alkane feed as calculated for an O/C ratio of 1.2. 

Table 5.7 shows the equilibrium reformate composition at four different O/C and S/C ratios as calculated from the data provided by Seo et al. [66]. The equilibrium composition of the reformate after water addition (provided as mol water per mol of... 

Table 5.7 Equilibrium reformate composition as achieved by steam supported partial oxidation (0/C= 1.2) and autothermal reforming (O/C = 0.88) of methane gas compositions are provided after the reformer and after water addition plus water-gas shift equilibrium at 250°C.

Figure 736 Carbon monoxide output versus reformate feed flow rate for two different compact aluminium heat-exchanger/ reactors tested separately and switched in series [328], test conditions 25-175 Lmin reformate 2.5-17.5 Lmin air O/CO ratio 3.5 synthetic reformate composition, 68.9vol.% Hj, 0.6vol.% CO, 22.4vol.% COj, 6.9vol.%H20 and 0.4vol.% CH3OH.

Figure 9.21 Efficiency with and without preferential or selective oxidation (SelOx) and reformate composition ofthe methane fuel processor as described by Heinzel et al. [17],...

Figure9.54 Reactor temperatures and dry reformate composition of the diesel reformer developed by Rosa et al. The gas analysis shows the gas composition of the fuel processor product [251].

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