Beets are first washed and cut into long thin strips called cossettes. The cossettes are fed into a diffuser which extracts the juice and discards the pulp to a dryer. The extracted juice travels to a purification station where it is treated with milk of lime, carbonated, and filtered. If increased purity is desired, this process is repeated.
Multiple effect evaporators boil the juice in a vacuum to create a thick syrup. The syrup is heated until crystallization occurs. This mixture of syrup and crystals is called massecuite. The massecuite is piped to a centrifugal separator which separates the crystals from the liquor. The liquor is reheated and sent through the evaporators again, or it is reboiled to form molasses. The sugar crystals are washed with hot water before being refined (Michigan History, Arts, & Libraries Website).
Raw beet sugar is refined in the same was that raw cane sugar is refined. The sugar is first washed with nearly saturated syrup to loosen molasses film in a process called affination. The crystals are separated from the syrup with a centrifuge, and then washed with hot water. The crystals are sent to a melter where they are combined with sweetwater and steam heated. The sugar solution is filtered and chemically clarified by phosphatation or carbonation. The sugar is decolorized through an absorption process, and sent through a series heaters, multiple effect evaporators, and vacuum pans which form a crystal-liquor mixture, similar to the process used in sugarcane processing. This mixture is centrifuged and the liquor completes the cycle 2-3 more times.
White sugar is usually obtained from the first two batches. Brown sugar is obtained the rest of the time. The sugar crystals are washed one last time, and dried at a temperature of approximately 230º F (110 º C). The crystals are cooled and packaged for retail sale. Other processed sugar products that may result are powdered sugar, liquid sugar, and molasses (EPA).
Natural Gas Technologies
Source: Overview Text from http://www.sentech.org/CHP4foodprocessing/sugar.htm#beetsugarmfg based on http://www.epa.gov/ttn/chief/ap42/ch09/final/c9s10-1a.pdf 4/2007;