Steady State Methods without Mass Transfer Enhancement

2 Steady State Methods without Mass Transfer Enhancement 

The steady state method is often used in continuous-flow operation with reaction, which is often the case in full-scale applications. In laboratory-scale investigations, the steady state method can be used with a semi-batch set-up (gas phase continuous) with reaction or a continuous-flow set-up (both gas and liquid phases continuous) with or without reaction. 

Since we know the mass of ozone transferred has to have reacted or left the system, it is relatively easy to determine the reaction rate for slow reactions, which are controlled by chemical kinetics with this method. For kinetic regimes with mass transfer enhancement, the two rates, mass transfer and reaction rate are interdependent. Whether kLa or kD can be determined in such a system and how depends on the regime. Possible methods are similar to those described below in Section B 3.3.3 (see Levenspiel and Godfrey, 1974). 

The following discussion assumes any reaction present is in the slow kinetic regime. It also combines the batch and continuous-flow models, since there is so little difference between them. 

For the calculation of kLa two methods based on the liquid and gas phase mass balances (equations 3-17 and 3-18) are possible. For steady state and the case with reaction only in the liquid phase one obtains  

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