Drying system, with flow characteristics

The powerful analogy that exists among momentum, heat, and mass transport permits useful values of convective mass transfer coefficients to be calculated from known values of convective heat transfer coefficients. For a particular drying system with a specific geometry and flow characteristics, the following relationship is recommended. " ... 

The drying behavior of single droplets and the resulting particle morphology were elucidated in for several reactive and nomeactive model systems. The flow characteristics inside the used levitator were simulated with CTD calculations and subsequently validated with experimental data. It was found that the evaporation process in the levitator is comparable to a spray process so that it offers the possibility to have access to the interaction of process and product properties, which are difficult to receive directly from a spray process itself. 

Despite the experience with batch reactors it may be worthwhile to operate continuous reactors also for fine chemicals. Continuously operated reactors only demand for one start-up and one shut-down during the production series for one product. This increases the operating time efficiency and prevents the deactivation of dry catalysts this implies that the reactor volume can be much smaller than for batch reactors. As to the reactor type for three phase systems an agitated slurry tank reactor [5,6] is not advisable, because of the good mixing characteristics. Specially for consecutive reaction systems the yields to desired products and selectivities will be considerably lower than in plug flow type reactor. The cocurrent down flow trickle flow reactor... 

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