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ProcessingThe Crushing ProcessThe soybean crushing process utilizes an all-natural heat treatment that denatures a portion of the protein to resist degradation in the rumen of the dairy cow. The finished meal will contain between 60 and 65 percent bypass protein. In the first step of the process, the whole raw soybeans are cleaned and cracked. The cracked beans are then dry heated at a specific temperature for a specific time to break open the oil cells found in the soybean. The next step in the process is to drop the heated cracks into the mechanical screw press to presses the oil out of the cracks. Two separate products are produced: crude soybean oil and bypass soybean meal.  Biodiesel Manufacturing Process Biodiesel is defined by the American Society For Testing and Materials (ASTM) as a fuel comprised of mono-alkyl esters of long chain fatty acids derived from vegetable oils or animal fats, designated B100. Consequently, biodiesel can be made from a wide range of vegetable oils and animal fats including: soy oil, Canola, palm oil, sunflower oil, waste vegetable oil and others. Because the output fuel characteristics of feedstocks can and do vary, a biodiesel manufacturer must certify that the product meets ASTM D 6751-03 specifications and report that data on a regular basis. This specification is particularly important if the biodiesel is to be blended with fossil diesel fuel and utilized in compression ignition engines. The chemical process of converting vegetable oils into biodiesel is called transesterification. Basically, methanol is mixed with a base catalyst, usually sodium hydroxide, and then mixed with a vegetable oil under mildly elevated temperatures and pressures. The Empire AgriFuel plant will initially use either soy oil or Canola Oil; both feedstocks produce biodiesel with the lowest cloud points (-3 F can be expected). This characteristic is important in fuels used in cold climates. Dry vegetable oil from one or more sources is blended to ensure consistency. The process stream consisting of the vegetable oil is then mixed with heated methylate and Methanol. Followng mixing, the process stream enters the first of 2 transesterification(a mix of methanol and sodium hydroxide). The majority (90 percent) of the chemical reaction producing biodiesel and glycerin takes place in the first reactor. The partially reacted process stream then enter the second reactor. Following the first reactor, a centrifuge separator is used to remove the glycerin produced and the glycerin stream is sent to storage.The process stream then enters the second reactor where the balance of the vegetable oil is converted to biodiesel and glycerin. Following the second reactor, glycerin is removed through the use of a second centrifuge separator. The process stream then enters a methanol recovery distillation unit that separates the unreacted methanol and biodiesel. The process stream, comprised mostly of biodiesel, is sent to the cascade settling units. The recovered methanol is recycled and mixed with the methylate prior to reentering the process. The cascade settling tanks remove any remaining glycerin and produce a biodiesel fuel with a minimal (parts per million) amount of caustic. Following the settling tanks, an ion exchange tower is utilized to neutralize any remaining catalyst and the biodiesel stream is then processed through a final filter prior to storage. The crude glycerin (80 percent) may be sold, used as a fuel or processed into pharmaceutical grade glycerin (99.9 percent pure) and sold. The resulting biodiesel is B100 and will meet ASTM D 6751-03 standards. |
