Reactors Carberry

In moving catalyst basket reactors, the flow regime is ill-defined and the contact between catalyst and gas can be poor even if well-mixed conditions for the fluid phase are achieved. Perhaps the most successful representative of this category is the Carberry reactor (1964, 1966). Even in this model only a single layer of catalyst can be charged in the cruciform catalyst basket because the fluid flows in a radial direction outward and... 

Figure 5.4-20. Basket-type reactor (Carberry reactor).

Carberry reactor The gas flows continuously through the tank-type reactor, whereas the catalyst is placed in rotating baskets in the reactor. This reactor is also experimental and suitable for catalysis as well as for adsorption studies (Figure 3.6). 

This reactor is a modification of the conventional moving-basket Carberry reactor. In the design of a falling-basket reactor for coal liquefaction, Alcorn et al. (1974) set five requirements ... 

The rotating-basket reactor (often known as the Carberry reactor) has been widely used for gas-solid as well as gas-liquid-solid reactions (see Fig. 5-6). Its construction is not very difficult, but it is more complex and expensive to build than a batch or fixed-bed reactor. The catalyst baskets can either be attached to the stirrer [Fig. 5-7(6)] or they can, themselves, be used as the stirrer paddles [Fig. 5-7(a)]. Furthermore, a small variety of rotating catalyst baskets are available (see Fig. 5-8). Baskets must, in general, be small in diameter, so that internal mass-transfer effects are minimized. 

Referring to Figure 3.5.2, the Carberry reactor contains paddles in which the catalyst is mounted and the paddles are rapidly rotated via connection to a control shaft in order to obtain good mixing between the gas phase and the catalyst. A Berty reactor consists of a stationary bed of catalyst that is contacted via circulation of the gas phase by impeller blades. The quality of mixing in this type of configuration... 

Fig. 4-3. Carberry reactor used in studies of ion-exchange kinetics on soils.

Laboratory reactors for fluid-solid and fluid-fluid reactions were described in Sections 3.1.6 and 3.3.2, respectively. The discussion in these sections is also useful for gas-liquid-solid reactions. A combination of the Carberry reactor (Eigure 11.7) and a stirred cell (Figure 11.14A) is useful for noncatalytic and catalytic reactions. Some discussion of these issues is presented in Case Studies CS8 and CSll as well as by Joshi et al. (1985) and Joglekar et al. (1991). 

CO or C02 was used as the tracer gas with nitrogen as the inert gas in these tests. A switching valve served to inject the pulse of tracer or to change from tracer to inert. Flow rates ranged from 1 to 40 std. cu. ft./hr. Measured at flowing conditions, this flow range is about that used in the Tajbl-Simons-Carberry reactor. Shaft speed was varied from 0 to 2500 r.p.m. Tracer response was measured by the in-line infrared analyzers. A typical response to a pulse test is shown in Figure 4. 

While for slurry reactors this operation can be realized simply by stirring, for heterogeneous catalytic reactions, special construction for complete gas mixing within the catalyst bed is required. Typical constructions for this purpose are the Berty reactor with its different modifications [96,97] and the Carberry reactor... 

In the Berty reactor, the catalyst is fixed in a basket through which gas is flown in a fast internal recycle forced by a turbine. The gas stirring in the Carberry reactor is realized by a rotating basket. 

Gas-solid (catalytic) Differential reactor Integral reactor Mixed (Carberry) reactor Mic roreactor Fluid-bed reactor Single-pellet reactor (Chapter 7)... 

FIGURE A9.7 Configuration alternatives for a gradientless reactor, (a) A stationary catalyst basket (Berty reactor), (b) a rotating catalyst basket (Carberry reactor), and (c) a recycle reactor. 

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