Factfile9 - Title

Wayne State upgrades

A generous donation of $100,000 from Ms Mollie Leonelli, widow of an alumnus, allowed Wayne State University (WSU) in Detroit to upgrade its Unit Operations Laboratory (now called the Leonelli UO Laboratory) in line with feedback from students and industry.

TA Assignment.
Two half-time TAs were assigned to commission the new equipment and upgrade some existing experiments. The assignment included developing procedures for the distillation and filtration units, upgrading the fluid bed experiments, and testing the procedures via running experiments. The results of this TA assignment were very effective.

Distillation Column.
Two different procedures were developed for Armfield's UOP3cc Distillation column. The first one was for the batch distillation of ethanol-water binary system, and the second was the demonstration of batch heterogeneous azeotropic distillation of acetic acid and water with ethyl acetate as the entrainer. A handheld refractometer was purchased to determine the product compositions. The column efficiencies at different reflux ratios for ethanol-water system were calculated by Fenske's and McCabe-Thiele's method.

Reflux Ratio
Number of
Theoretical Plates
Efficiency (%)
Method
Total
1.5
19.3
Fenske
4
1.8
22.4
Fenske
3
1.6
19.4
Fenske
3
3
37.5
McCabe-Thiele
Table - The column efficiencies for EtOH-Water system.

Fixed and Fluidized Bed.
The undergraduate students always had difficulties in the comparison of their theoretical and experimental results. The TAs discovered that this problem is eliminated via specifying the void fractions for each experiment.
The bed void fraction for the air and water-side columns were determined based on the agreement between the experimental and the theoretical results. The void fraction was found to be 0.45 for the air fixed bed experiment (Ergun Equation) and the fluidization point determined theoretically using the Carman-Kozney Equation was exactly at the same air flow rate as the experimentally observed fluidization point (Fig A). For the water-side column, the best agreement between the theoretical and the experimental results was achieved when the bed porosity was set to 0.17 for fixed bed state and 0.55 for the fluidized bed state (Fig B).

Summary.
After this WSU UO Lab upgrade we now have 13 excellent experiments for our students. The concept of using part time TAs was very effective.

Figures:
Pressure drop as a function of air flow rate in the (A) air-side column (B) water side column.

Air-side column
Fig (A) Air-side column

Water-side column
Fig (B) Water-side column


The work and article were prepared by B. Saygili and P. Kohle directed by Professor J. F. Louvar.

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