NASA 1996 SBIR Phase I

PROPOSAL NUMBER : 96-1 16.08-7770F

PROJECT TITLE : Biomass Conversion to High Solids Pumpable Slurries.


The inedible portion of biomass (i.e., hemicellulose, cellulose, and lignin) in closed regenerative biosystems must be reprocessed. Past attempts to form pumpable biomass slurries have been met with limited success as untreated cellulosic fibers form very viscous slurries at solids loading as low as 1wt%. Biomass containing hemicellulose can be acid hydrolyzed and mechanically emulsified with air to produce a highly stable (non-settling) and pumpable high solids (~30wt%) non-Newtonian slurry. The advantages of an acid hydrolysis process include simple sugar formation for further processing (i.e., enzymatic) and ease of pumping with either moyno (progressive cavity) or piston pumps. For Phase I, it is proposed to pretreat wheat straw, rice straw, and potato residue. Rice straw is particularly high in silica and will provide a worst case model. Maximum solids concentration will be demonstrated with conventional pumps (i.e., progressive cavity and piston). The non-Newtonian behavior of the biomass slurry will be defined. A Phase II effort will progress to a combined acid hydrolysis pretreatment/pump system where acid hydrolysis occurs in the pumping system itself. A twin screw extruder pump system will double as the pretreatment chamber and the pump itself. The principal advantage is that a high solids slurry can be pumped directly into a subsequent high or low pressure reactor for further processing (i.e., biological, enzymatic, physiochemical, or thermochemical).
For use by the Federal Government, the primary commercial application will for the pretreatment of inedible crop biomass in reclamation systems supporting long duration missions in space such as a Lunar base, or a Mars mission. The proposed research will result in the development of a compact and reliable biomass pretreatment/pumping system for biomass reprocessing that can be operated in both land and microgravity environments. The natural extension of this innovation will be to include biological processing to remove cellulose and lignin in modular form. Private sector commercial potential encompasses a broad spectrum of adaptations to meet specific waste biomass conversion (e.g., food and chemical(s) production). NAME AND ADDRESS OF PRINCIPAL Carlos Figueroa, P.E. Umpqua Research Company P.O. Box 609 Myrtle Creek, OR 97457
Umpqua Research Company
P.O. Box 609
Myrtle Creek, OR 97457