Sugar Beet (Beta vulgaris L) as a Biofuel Feedstock in the United States

摘要

Sugar beet is a biennial plant, which produces an enlarged root and hypocotyl in the first year, in which it stores sucrose to provide energy to flower in the next season. Technically, conversion of sugar to ethanol is a simple process requiring only yeast fermentation. A 2006 USDA study calculated the yield of ethanol from the sucrose in a sugar beet was 103.5 L per tonne of root (wet weight). Life cycle analysis (LCA) indicates that bioethanol from sugar beet reduces green house gases as well or better than maize. Both nitrogen and water use efficiency may be superior to maize on average. However, sugar beet with an area of 465,000 ha in 2009, compared with about 32 million ha of maize, likely will not displace maize as the primary feedstock for bioethanol in the U.S. More likely, co-products like pulp and molasses will find use as bioenergy feedstocks, probably for high value specialty fuels or as feedstocks for a whole generation of petroleum plastic substitutes.