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Else_AIEC-INGLE_cH003.qxd 7/13/2006 1:46 PM Page 175
3.7 Three-Phase Fixed Beds: Trickle-Bed and Ped Bubble-Bed Reactors ack 175

where

H 1
K
1 1 1 (3.379)

k a (
Ka ( LG A ) f u A ) b m k
L
and

C  
( R A ) a L G A )  AG C AL  ( a k f u A C AL C AS b m k AS (3.380)
K
)
C
(
L
 H A 
Using the general material balances presented in the previous paragraph and the abo v e
approach: for reactant at steady state, and for a volume element that extends across the
A,
reactor,
d F AG
( A ) R 0 (3.381)
d V

for reactant B (for plug flow of liquid),

C d
u BL ka ( C ) C 0 (3.382)
sL fu B BL BS
z d

or
C d
u BL ) 0 (3.383)
(
R
sL B
z d
where
( ) R
( ka ) C C ( R ) A (3.384)
fu B BL BS B
a
For the case of = 1 and first-order reaction rate with respect to A and B

(
( ka fu B ) C BL C B ( R ) R ) b k C C (3.385)
m
AS
BS
BS
A
v e approach, and using the abo we can derie the equations used by Fogler (1999): v
( R ) C o (3.386)
K
A A AG