Considerations for Intensified Monolith Processes

The details of designing a multiphase monolith columns is a topic in itself, and the interested reader is referred to Kreutzer et al. [13]. Here, several aspects that follow immediately from the scaling analysis presented above are discussed. 

The proper distribution of gas and hquid over the column cross section is crucial for monoHths, because inside a monolith block no redistribution can occur. Fortunately, static mixers can be used that combine a good distribution with 

Equations (6.9) and (6.12) show that the mass transfer is only a mild function of the channel diameter. If dust tolerance is important, it seems worthwhile to sacrifice some interfacial area. On the other hand, for G/L/S reactors the channel size is crucial, and channel size should be increased only as a last resort. 

The G/L/S mass transfer improves with lower throughput, so it makes sense to operate at the lowest possible practical flowrates. The lower limit is set (1) by the requirement of Taylor flow, for which 2-3 cm/s is enough for the smaller channels ( 200cpsi) and (2) the requirement of stable gas/liquid flow, which may require somewhat higher flow rates [20]. The ratio of gas to liquid throughput hardly affects the mass-transfer rate, but a sizeable gas holdup may be required if entire bubbles may otherwise be completely dissolved, resulting in the loss of the Taylor-flow characteristics. 

The G/L mass transfer scales only with and increasing or decreasing 

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