The ‘Low Temperature Steep Delignification’ (LTSD) is a highly efficient, cost effective, process for the pretreatment of a range of biomass under mild operating conditions producing no toxic chemicals or fermentation inhibitors.

Background: The pretreatment of biomass material disrupts the natural structure of lignocellulose allowing cellulase enzymes to effectively hydrolyze the cellulose and the hemicellulose portions into base sugars.  Most pretreatment processes are associated with extreme temperatures/pressures, high cost equipment, high chemical / acid loading levels, and the production of toxic co-products that inhibit fermentation.

Description: The LTSD process is a highly effective biomass pretreatment process with optimal operating conditions characterized by low temperatures and minimal chemical loading levels.  Lignocellulosic biomass treated in the LTSD process produces two streams: 1) a ‘pulp’ stream, rich in cellulose & hemicellulose, and 2) a soluble stream high in recoverable lignin.

Applications: The LTSD is an effective and economical process for the disruption and separation of lignocellulosic biomass, increasing the rate and effectiveness of enzymatic hydrolysis in commercial biomass / fermentation processing facilities.

Advantages of the LTSD:

• Mild Operating Conditions: Low Temperatures & Pressures
• Minimal Chemical Input Requirement & High Rate of Recovery
• Production of No Toxic Chemicals or Fermentation Inhibitors
• Highly Effective Process with Fiber Recovery Rate of 90+%
• Effective on a Variety of Biomass (grasses, woody biomass, ag)
• Soluble Lignin Stream Allows Recovery of Lignate Co-Product,
• LTSD Equipment Does Not Require Specialty, High Cost, Alloys,

R&D Background: The LTSD process has been developed & improved over the last 15 years by BPI, being successfully demonstrated on the laboratory & pilot scales on a variety of biomass materials: corn stover, wheat straw, switch grass, miscanthus, cane & sorghum bagasse, oat hulls, wood chips, saw dust, corn fiber, hybrid poplar, and forestry residue.

Technology Maturity: Commercial, a commercial demonstration of the LTSD that will process 10,000 lbs of biomass per hour will be completed in early 2010.  A commercial wheat straw to ethanol facility utilizing the LTSD pretreatment to process 45,000 tons of biomass per year is slated to begin construction this year at Evolution Resources, Moses Lake Bio-Refinery.