ST2-07: Ethanol from straw-now a reality in Denmark

Inbicon A/S, a subsidiary of DONG Energy A/S, has opened a demonstration plant for the conversion of wheat straw to ethanol in November 2009 with a capacity of 30,000 tonnes of wheat straw to produce 5.4 million liter of ethanol, 13,000 tonnes of lignin pellets and 11,000 tonnes of C5 molasses per year. Danish power companies started using biomass in the 1990s, and now DONG Energy uses more than 500,000 tonnes of wheat straw for power and heat generation. To add more value to the raw material, a process was developed to produce ethanol, and in 2002 an R&D project ("Co-production of biofuels") partly funded by the European Commission was initiated. Several technological breakthroughs were achieved, and pilot plants with design capacities of 2.4 and 24 tonnes per day of wheat straw were inaugurated in 2003 and 2005, respectively. In February 2010 Inbicon signed its first license contract with Mitsui Engineering & Shipbuilding (Japan). The core technology is hydrothermal pretreatment and enzymatic hydrolysis using the high gravity principle. Very efficient liquefaction has been demonstrated with very low enzyme doses, and the fermentation is very robust. Inbicon cooperates with Novozymes and Genencor ensuring applicability of the most advanced enzyme technologies. The process requires no chemicals and it can work at high dry matter content (30 - 40 %).