Experimental Determination of RTD in Flow Reactors

For practical purposes, it is beneficial to characterize distribution functions by a few characteristic terms as the mean residence time and the variance around the mean. The mean residence time t) corresponds to the first moment of the distribution function, E t). 

If the density of the fluid does not change in the reactor (Vg = Vom), the mean residence time corresponds to the space time. 

The variance of the distribution is obtained from the second moment of the distribution function. 

The skewness (sk) is a measure for the deviation from the symmetrical distribution. It is characterized by the third moment of the distribution defined with 

The higher moments of the RTD are of little practical interest because they are difficult to obtain experimentally with the required accuracy. 

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Experimental Determination of RTD in Flow Reactors 91 We then obtain the following relationships for the distribution functions... 

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