(94e) Flow Pattern Optimization of a Sieve Plate Extraction Column Using CFD Simulation and PIV Measurement

Present work deals with flow pattern
optimization of the continuous phase in a sieve plate extraction column using both
computational fluid dynamics (CFD) simulation and particle image velocimetry (PIV) measurement. Firstly, flow pattern of a sieve
plate extraction column (SPEC) with traditional configuration was simulated and
it was found that there was a very large reverse flow region between every two
plates. Then, flow pattern was optimized with the objective of minimizing reverse
flow area since the reverse flow can decrease the mass transfer efficiency. Step
by step, internal structure of the column was modified to minimize the reverse
flow area and with the modification, flow pattern of the continuous phase was
optimized. The strategies consist of inclining downcomers, adding diversion baffles, slotting the downcomers
and diversion baffles, adjusting the number and size of slots and fixing small baffles laterally at the top slots on downcomers.
In the course of evolution, five generations (11 types) of SPEC with different internal
configuration were proposed and flow patterns in these columns were investigated.
Finally, an optimal flow pattern nearly no reverse flow region was obtained.
PIV experiments of three types of columns in 11 were carried out and it was
found that the results of simulations and experiments are in good agreement. Besides,
the mass transfer performances of all columns were investigated by CFD simulation
and it was found that mass transfer efficiency was improved as the flow pattern
was optimized. The flow pattern optimization strategies proposed here can be
extended to the design of other process equipment such as distillation and
reaction.

Keywords: flow pattern optimization, extraction column, CFD, PIV