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Question 18.7: What is the F factor at the top of the column in Example 18.......

What is the F factor at the top of the column in Example 18.6 if the vapor velocity is the maximum allowable?

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From Eq. (18.71) the F factor is

F\equiv u{\sqrt{\rho_{V}}}                (18.71)

F=u_{c}{\sqrt{\rho_{V}}}

=2.23{\sqrt{1.15}}=2.39

As shown by Fig. 18.34, this is a reasonable value for a sieve-plate column at 1 atm pressure.

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