Biorefineries
Biorefineries Overview As a petroleum refinery uses petroleum as the major input and processes it into many different products, a biorefinery uses biomass as the major input and processes it into many different products. Wet-mill and dry-mill corn processing plants and pulp and paper mills can be categorized as biorefineries since they produce multiple products from biomass. Ethanol production facilities produce ethanol and other products from the sugar and starch components of biomass. As of September 2008, the Renewable Fuels Association listed 168 operating ethanol biorefineries with a total production capacity of 9,961 million gallon per year (MGY). New construction and expansion would add another 3,790 MGY. Distillers grains, a high-value, protein rich product being used for livestock feed is the major co-product of the existing dry-mill ethanol biorefineries. Wet-mill ethanol biorefineries have the capacity to produce high fructose corn syrup, and a wide variety of chemical feedstocks such as citric acid, lactic acid, lysine and other products as well as ethanol. Research over the past several years has developed several technologies that have the capability of converting many types of lignocellulosic biomass resources into a wide range of products. The goal is for biorefineries to produce both high-volume liquid fuels and high-value chemicals or products in order to address national energy needs while enhancing operation economics. History was made in 2007 with the ground breaking for construction of the first commercial-scale lignocellulosic ethanol biorefinery in the U.S. The Range Fuels facility near Soperton, Georgia will use initially use wood residues from timber harvesting to produce ethanol and other products. Pulp and Papers mills are existing biorefineries that produce heat, and electricity as well as pulp or paper and some chemicals, but they also have the potential of producing very large amounts of biofuels and biomass power from processing residuals such as bark and black liquor. Three pulp production facilities were included among the 9 awarded funding in 2008 for building small-scale prototype biorefineries to test new ideas.
Source: National Renewable Energy Laboratory, Biomass Program, July 2008. http://www.nrel.gov/biomass/biorefinery.html |
Two of the emerging biorefinery platforms are the sugar platform
and the thermochemical platform (also known as the syngas platform)
illustrated below. Sugar platform biorefineries would break biomass
down into different types of component sugars for fermentation
or other biological processing into various fuels and chemicals.
Thermochemical biorefineries would convert biomass to synthesis
gas (hydrogen and carbon monoxide) or pyrolysis oil, the various
components of which could be directly used as fuel. Several other
biorefinery platforms are included among the medium and small-scale
projects being cost-shared by the U.S. Department of Energy,
state funding, and private investment.