Shell and tube type reactor

In all three of these cases, the performance of the reactor and the heat exchanger are coupled. It is not correct to analyze one without the other. In this section, an exanple of the performance of a shell-and-tube-type reactor (tube bundle containing catalyst immersed in a pool of boiling water) with heat removal is used to illustrate the interrelationship between reactor performance and heat transfer. In Chapter 20. other exanples of reactor performance are presented. 

Oxidation Step. A review of mechanistic studies of partial oxidation of propylene has appeared (58). The oxidation process flow sheet (Fig. 2) shows equipment and typical operating conditions. The reactors are of the fixed-bed shell-and-tube type (about 3—5 mlong and 2.5 cm in diameter) with a molten salt coolant on the shell side. The tubes are packed with catalyst, a small amount of inert material at the top serving as a preheater section for the feed gases. Vaporized propylene is mixed with steam and ak and fed to the first-stage reactor. The feed composition is typically 5—7% propylene, 10—30%... 

The first reaction is exothermic, and the second is endothermic. Overall, the reaction evolves considerable heat. Figure 7.1 shows two alternative reactor designs2. Figure 7.1a shows a shell-and-tube type of device that generates steam on the shell side. The temperature profile shows a peak shortly after the reactor inlet because of a... 

The Hrst type of generic model for shell-and-tube membrane reactors refers to a nonisothermal packed-bed catalytic membrane tubular reactor (PBCMTR) whose cross-sectional view is shown in Figure lO.l. Mathematical models for this type of membrane reactor have been reviewed quite extensively by Tsotsis et al. [1993b]. 

As a building block for simulating more complex and practical membrane reactors, various membrane reactor models with simple geometries available from the literature have been reviewed. Four types of shell-and-tube membrane reactor models are presented packed-bed catalytic membrane reactors (a special case of which is catalytic membrane reactors), fluidized-bed catalytic membrane reactors, catalytic non-permselecdve membrane reactors with an opposing reactants geometry and catalytic non-permselective membrane multiphase reactors. Both dense and porous inorganic membranes have been considered. 

The vapor-phase decomposition of methyl-/-butyl ether (MTBE) into methanol and isobutene was examined in a shell- and tube-type catalytic membrane reactor by Choi and... 

Following completion of the bench scale test program, an engineering contractor conducted a study and prepared the preliminary design for a pilot plant having a nominal production capacity of 20 short tons of sulfur/day when treating pure sulfur dioxide. This study found that fixed-bed catalysis was more practical. The preliminary pilot plant design, therefore, provided for a fixed-bed primary reactor of the shell-and-tube type in which the catalyst would be in the tubes. 

Reactors for Low-Temperature Operation The preceding discussion in Section 3.3.1b shows that the low-temperature mode is used for obtaining higher carbon number hydrocarbons (diesel/waxes). Sasol started this mode with five shell- and tube-type fixed beds in 1955. These reactors operated at 2.7 MPa and 230 °C, producing 21,0(X)... 

When heat of reaction has to be removed through the reactor walls, a shell and tube type construction can be used, very similar to a conunon heat exchanger. In most cases the catalyst is put inside the tubes, and a cooling medium passes on the shell side. Occasionally, the catalyst is put in the shell, and the cooling medium is passed through the tubes. However, the first arrangement appears to have advantages for easy replacement of the catalyst. 

Figure 19.1 Shell-and-Tube-Type Packed-Bed Reactor...

At this time, we are unsure as to whether a packed-bed reactor (shell-and-tube type, modeled as a plug flow reactor) or a fluidized-bed reactor (modeled as an isothermal plug flow reactor with 10% feed gas... 

In this chapter different types of heat exchanger will be analyzed for their dynamic behavior. The first type is the shell and tube type, where steam condenses inside the tubes and the contents of a well-mixed tank or reactor have to be heated. The second type is also a shell and tube type heat exchanger, where the steam condenses outside the tubes (shell-side) and the liquid to be heated flows through the tubes. The last type is the countercurrent heat exchanger, in which the liquid to be heated flows countercurrent to the heating medium. 

Choi J S, Song 1 K and Lee W Y (2001), Performance of shell and tube-type membrane reactors equipped with heteropolyadd-polymer composite catalytic... 

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