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A. Frías-Ferrer, J. González-García, V. Montiel and A. Aldaz
Dpto. Química Física
Universidad Alicante
Conception of thereactor design
Ex: filter press cells, rotating cilinderelectrode, etc..
Reaction Design
It can be done before(ex, several organicreactions) or in parallel to the designstage
Laboratory scale
Usually in small cells (up to 1 A). Ideally theworking conditionsshould be similar toindustrial system. Pilot plant scale
Very important for the designprocess. Typical currents up to 100 A. A lot of projects failin this stage.
Industrial scale
About 2 years after theinitial reactor conception.Typical currents up to 1000 A. (pharmaceuticalproducts)
Reactor Characterisation, modelling and modifications
There are severalmodifications since the initialdesign. Usually uneven flowdistributions or currentdeficiencies are corrected
Studies
• Hydrodynamics
• Mass Transport
•RTD Studies
•CFD Studies
•Direct flow visualization
•Km Studies
•RTD Studies
UA63.03
Vstat
Vdyn
cstat
cdyn
0
0,02
0,04
0,06
0,08
0,1
0,12
0,14
0,16
0,18
0,2
0 5 10 15 20 25 30 35 40 45 50
t / s
E
0 10 20 30 40 50
0.00
0.05
0.10
0.15
0.20
Re = 129
Experimental Model
E
t / s
Cu2+ + 2e- → CuRe ↑↑↑↑
∂∂
+∂∂
∂∂+
∂∂−=
∂∂
+∂∂
i
j
j
i
jij
jii
x
v
x
v
xx
p
x
vv
t
v ηρ Finite Element Method
CFD (Computer Fluid Dynamics)
Navier - Stokes
Vinlet
Pressure
Vstat
Vdyn
cstat
cdyn
When a compartment is working at a giving Reynolds number we are supposing that all the compartment is working at the flow velocity that generates that Re. But it is not true. There are fast areas and slow areas or dead volumes inside the compartment. In this way, we can estimate that all the points inside the compartment working under a 45% of the theoretic velocity for this Re number are dead zones or dead volumes. And all the points working above that velocity are active areas.
Re Active Zone
129 58 %
200 58 %
271 59 %
414 74 %
Re Active Zone
129 63 %
200 55 %
271 55 %
414 74 %
Re Error betweenRTD – CFD
129 8 %
200 4.5 %
271 7 %
414 0.014 %
