Shock treatment of corn stover

Area of Science:

• Biotechnology
• Chemical Engineering
• Biomass Conversion

Background:

• Corn stover is a promising lignocellulosic biomass for biofuel production.
• Improving the enzymatic digestibility of corn stover is crucial for efficient conversion.
• Current methods for biomass pretreatment require optimization for cost-effectiveness.

Purpose of the Study:

• To investigate the efficacy of shock treatment in enhancing corn stover digestibility.
• To determine the optimal conditions for shock treatment parameters.
• To assess the potential for commercial-scale application of this technology.

Main Methods:

• Lime-treated corn stover slurry subjected to shock waves generated by shotgun shells or gas detonations.
• Varied parameters including pressure, depth, solids concentration, and gas mixtures.
• Enzymatic digestibility assays conducted to quantify glucan conversion.

Main Results:

• High pressurization rates (108,000 MPa/s via shotgun, 4,160,000 MPa/s via H2/O2 detonation) significantly improved enzymatic digestibility.
• Stoichiometric propane/air deflagration (37.2 MPa/s) did not enhance digestibility.
• Enzyme loading was reduced by approximately twofold while maintaining conversion rates.
• A process cycling three 0.575 m³ vessels every 7.5 s demonstrated commercial viability (2,000 tons/day).

Conclusions:

• Shock treatment, particularly with high pressurization rates, is an effective method for enhancing corn stover enzymatic digestibility.
• This technology offers a pathway to reduce enzyme requirements and improve the economics of biofuel production from corn stover.
• The rapid cycling capability suggests feasibility for large-scale industrial application.