Friday, July 10, 2009
 
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Carbon Dioxide

What is it? Carbon dioxide (CO2) is a colorless, odorless, tasteless, naturally-occurring chemical compound composed of one carbon and two oxygen atoms.

How is it used? Carbon dioxide is valuable because of its many uses in industry. It is available as a liquid under high pressure in steel cylinders, as a low-temperature liquid under lower pressures, and as the solid dry ice when cooled to -109.3 degrees F (or -78.5 degrees C). The follow is a partial list of carbon dioxide's uses:

  • Beverage Carbonate
    In its gaseous form, carbon dioxide provides the sparkle and fizz of carbonated beverages because it dissolves into water when placed under pressure and is released as bubbles when the carbonated beverage is exposed to atmospheric pressure.
  • Food Preservative (in gaseous form)
    In its gaseous form, carbon dioxide prevents spoilage caused by oxidation when injected and sealed into packaging containing consumables by displacing oxygen and providing a non-reactive atmosphere for storage.
  • Fire Extinguisher
    In its gaseous form, carbon dioxide is an effective flame retardant for electrical fires, gas fires, grease fires, and fires caused by other flammable liquids because it is heavier than air, non-flammable, and when dispersed in large amounts, smothers a fire by displacing the oxygen needed to feed it.
  • Oil Recovery Tool
    In its gaseous form, carbon dioxide is effective in improving oil recovery rates from oilfields because it dissolves into the oil, increasing its volume, thinning it, and making it less sticky so that it flows more easily.
  • Food Refrigerant
    As dry ice, carbon dioxide is used in the food industry to refrigerate and flash-freeze food products such as ice cream, fruits, vegetables, and meats.
  • Plumbing Aid
    As dry ice, carbon dioxide is used to freeze water in valveless pipes, allowing repair without flooding.
  • Blasting Material
    As dry ice, carbon dioxide is used in cleaning applications by forming it into tiny particles and accelerating it to supersonic speed with a blast gun to "dry ice blast" unwanted coatings from substrate.

Where is it collected in the production process? Carbon dioxide is a co-product of drymill ethanol production. For every bushel (56 pounds) of corn used, about 2.8 gallons of ethanol and 17 lbs. of carbon dioxide are produced. Released during the fermentation stage of production, carbon dioxide is collected, cleaned of any residual alcohol and compressed for transportation to market.


Distillers Grains

What are they? Distiller's grains are the non-fermentable components of corn. These components are rich in essential nutrients. The concentrations of the essential nutrients are generally around three times that found in the corn meal used to produce it.

How is it used? Scientific research has demonstrated that distiller's grains are an excellent, all-natural, low-cost source of beneficial fats, cereal proteins, vitamins, and minerals. They are well suited to ruminant animal diets and are an especially superior supplement in feed rations beef and dairy cattle (20-30% of total diet). They are also used to a lesser degree in feed rations for poultry, swine, sheep, and fish.

Where is it collected in the production process? Distiller's grains are a co-product of drymill ethanol production. For every bushel (56 pounds) of corn used, about 2.8 gallons of ethanol and 16 lbs. of distiller's grains are produced.

After the distillation stage of production, the remaining solids are sent through a centrifuge that separates the coarse grain, or Wet Distiller's Grains (WDG), from the solubles (a liquid with about 5% solids). The solubles are concentrated to about 30% solids through evaporation, creating Condensed Distiller's Solubles (CDS) or "syrup."

Wet Distiller's Grains can be mixed with the syrup to produce Wet Distiller's Grains with Solubles (WDGS) or dried to produce Dried Distiller's Grains (DDG). The WDGS can be dried as well to produce Dried Distiller's Grains with Solubles (DDGS), and the DDG can be mixed with syrup to produce Modified Wet Distiller's Grains with Solubles (MWDGS).