Ethanol Production and Biofuels

Application: Ethanol Production  

Ethanol scrubbers are sometimes referred to as fermentation scrubbers.  The widest use of ethanol scrubbers are found in fuel ethanol production facilities where plants combine process streams from fermentation and process vents that contain carbon dioxide (CO2) and ethanol (C2H5OH). The exhaust gas also contains low concentrations of soluble and insoluble volatile organic compounds (VOCs) including:



  • Ethanol (CH4O)
  • Formic acid (CH2O2)
  • Lactic acid (C3H6O2)
  • Acetic acid (C2H4O2)
  • Amyl Alcohol (C5H12O)
  • Formaldehyde (CH2O)
  • Acetone (C3H6O)
  • Acrolein (C3H4O)
  • Acetaldehyde (C2H4O)
  • Ethyl Acetate (C4H8O2

The outlet emission limits for the insoluble VOCs in some states may require post processing like a regenerative thermal oxidizer (RTO) or the use of sodium bisulfite in the scrubber. Ethanol scrubbers can also be found in other types of facilities like distilleries or cellulosic ethanol plants.

Exhaust Sources:

  • Fermentation Tanks and Process Vents


  • Ethanol
  • VOCs



  • Presentation: 2009 Fuel Ethanol Workshop (FEW)
  • Video: Packed bed scrubber