Modular, Horizontal Micro-Distillation Column

A horizontal micro-distillation column using metal foam as a distillation packing is presented. Two designs were used in the experiments; a single piece column manufactured from steel and a modular column manufactured from copper. Copper was chosen to enhance the heat transfer in the longitudinal direction. Modular structure was chosen to enable the testing of different designs for the reboiler and the condenser.

The use of metal foam as distillation column packing was studied with and without an empty space above the foam; the column was found to perform markedly better without. Filling the foam completely with liquid significantly improved the separation efficiency. Best measured separation efficiency was 18 ideal steps within 290 mm of metal foam packing, which equals to a HETP of 16 mm. The columns were simple and safe to operate and were run unmanned for up to 3 weeks.

The distillation columns presented will make it possible to further miniaturize mini-plant technology to a micro-plant. They may enable the running of longer test runs for the studying of accumulation of impurities in recycles. They may also enable faster and cheaper process development and may allow research in universities to go further in testing ideas in process development