Design, Fabrication, and Preliminary Testing of a Laboratory-scale Bubble-cap Distilling Column

Author : Molin, Roman Wenceslao C.
Major Adviser : Alcanzare, Edilberto A.
Committee Members :
Year : 1991
Month : March
Type : Thesis
Degree: BS
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A laboratory scale bubble-cap distilling column was designed, fabricated and preliminary tested. The aim of was to produce 70 mole percent ethanol distillate and 1 mole percent bottoms product from 10 mole percent ethanol feed.

The design of the column included the bubble-cap-riser assembly and the tray design. It involved flooding and entrainment considerations. The tray dynamics at the top tray were also evaluated. The column was fabricated based on the designed values. In addition, temperature and sampling ports were attached to the column so as to facilitate the gathering of data during testing. The final fabricated equipment had practically no leaks. Preliminary testing was done with a single pass shell-and-tube condenser, double pass shell-and-tube reboiler and steam generator. The feed used was 3.88 mole percent ethanol, and the distillate and bottoms produced were 17.46 and 0.1958 mole percent ethanol, respectively. Based from these compositions, overall efficiency obtained was 27.27 percent. This was not a reflection of the actual efficiency of the column as accounted from the following factors: low feed concentration, difficulty in regulating the flowrates of different streams, condenser and reboiler specifications, inaccuracy of some flowrate and temperature measurements, and others. Recommendations were provided to attain satisfactory results during testing and to attain the actual efficiency of the column.

It was concluded that the bubble-cap distilling column was operational, although the operating conditions from the design should be met to evaluate the right performance or efficiency of the column.

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