16-04: Scale up of steam pretreatment of biomass for production of fermentable sugars

Abengoa Bioenergy, the Global Biotech Ethanol Company, is building a 25 MMGPY biomass-to-ethanol plant in Hugoton, KS.  Startup of the plant is scheduled for late 2013.  The plant utilizes dilute-acid catalyzed steam pretreatment to achieve high enzymatic sugar yields from herbaceous feedstock such as corn stover, wheat straw, and switchgrass.  The Abengoa pretreatment technology has been developed and proven at pilot and demonstration scale since 2007.  This robust pretreatment technology can process a variety of lignocellulosic feedstock and responds very well to feedstock variation while maintaining high sugar yield and concentration and low level of inhibitors in continuous operation. 

Successful scale up of steam pretreatment incorporates the characteristics of incoming feedstock (such as composition, particle size, contaminants, and moisture content) as well as desired properties of the pretreated material (composition, particle size, moisture content, temperature, and pH) in the process design.  Processing biomass feedstock and high-solid slurries of pretreated material requires proper selection and integration of equipment to ensure reliable operation and low equipment maintenance.  This presentation provides an overview of the challenges in scaling up steam pretreatment of biomass, process control strategy, and available commercial equipment.