Temperature profiles, reactors methanol synthesis

Temperature profiles, reactors ammonia synthesis, 582, 584 cement kiln, 590 cracking of petroleum, 595 endo- and exothermic processes, 584 jacketed tubular reactor, 584 methanol synthesis, 580 phosgene synthesis, 594 reactor with internal heat exchange, 584 sulfur dioxide oxidation, 580... 

Fig. 2 shows the I.C.I. warm-shot methanol synthesis loop. The adiabatic methanol reactor has multiple catalyst beds which cure quenched with warm reactant gas that control the methanol converter s temperature profile and methanol outlet concentration as portrayed in Fig. 3.. In this adiabatic quench redctor methanol loop scheme, the main features are ...

This figure clearly illustrates that the range within which multiple steady states can occur is very narrow. It is true that, as Hlavacek and Hofmann calculated, the adiabatic temperature rise is sufficiently high in ammonia, methanol and oxo-synthesis and in ethylene, naphthalene, and o-xylene oxidation. None of the reactions are carried out in adiabatic reactors, however, although multibed adiabatic reactors are sometimes used. According to Beskov (mentioned in Hlavacek and Hofmann) in methanol synthesis the effect of axial mixing would have to be taken into account when Pe < 30. In industrial methanol synthesis reactors Pe is of the order of 600 and more. In ethylene oxidation Pe would have to be smaller than 200 for axial effective transport to be of some importance, but in industrial practice Pe exceeds 2500. Baddour et al. in their simulation of the TVA ammonia synthesis converter found that the axial diffusion of heat altered the steady-state temperature profile by less than 0.6°C. Therefore, the length of... 

Examples of a simultaneous numerical solution of molar and energy balance equations for the gas bulk and catalyst particles are introduced in Figure 5.27, in which the concentration and temperature profiles in a methanol synthesis reactor are analyzed. The methanol synthesis reaction, CO -F 2H2 CH3OH, is a strongly exothermic and diffusion-limited reaction. This implies that concentration gradients emerge in the catalyst particles, whereas the heat conductivity of the particles is so good that the catalyst particles are practically isothermal. 

Methanol Synthesis. Form of Temperature Profile with 3 lypes of Reactors. 

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