The NES Perspective: Biofuel Vacuum Pumps and Compressors

The biofuels industry thrives by converting biological materials into usable fuels like ethanol, biodiesel, and biogas. This begins with the selection and sourcing of feedstocks, which vary depending on regional availability and fuel type. Anything from sugarcane and corn to organic waste can be utilized for the production of this green energy. The raw materials undergo rigorous treatment to prepare them for further chemical or biological processing.

In ethanol production, feedstocks (like corn) are first milled and hydrolyzed such that they release fermentable sugars. The addition of yeast converts these sugars into ethanol via fermentation. The fermentation broth is then purified; at this point, the process of distillation is essential.

Distillation encompasses the use of controlled temperature and pressure in order to selectively evaporate and condense elements of a mixture such that the process yields high-purity constituents like the ethanol and water in the broth. As the pressure lowers, the boiling point required for evaporation of the constituent materials also lowers, making it easier to selectively vaporize the mixture with lower temperature. This translates to safer operation, as the ethanol is not exposed to high temperatures, as well as a decrease in operational costs as required heat energy decreases.

Membrane pervaporation is another critical separation technique that only advances further through current research. This process makes use of a selective membrane that will allow for the capture of ethanol while allowing the other constituents, like water and byproducts, to pass through or to be captured earlier by a different selective membrane. Through this exhaustive separation method, extremely high-purity ethanol can be produced. Vacuum systems also contribute to the recovery of solvents used in the fermentation broth mixing process, which are introduced to further extract sugars from the feedstock.

Biogas production from organic waste or manure is based off of anaerobic digestion. The waste is sent through tanks full of archaea and methanogens; the archaea break the waste down into sugars that can then be digested by the anaerobic methanogens to produce methane and carbon dioxide. Water vapor and hydrogen sulfide are also byproducts of the digestion reaction and need to be removed.