Hot Water Extraction of Lignocellulosic Biomass
Hot Water Extraction is the process Applied Biorefinery Sciences uses to cook woody biomass in plain water at elevated temperatures (~150-200°C). Under heat and pressure, hemicellulose and other compounds are freed from their bonds inside the woody biomass, and migrate into the hot water bath. The environment is not sufficient to break down the cellulose matrix, so the residual biomass, although darker in color, remains structurally intact. The processed material is less reactive to water, and therefore improved for manufacturing traditional wood products such as fuel pellets, pulp and paper, fiberboard, or composites, as well as new technology wood products.
Compared to raw wood chips, hot water extracted wood chips have:
- Darker color
- Its structure (cellulose & lignin) still intact
- Same volume
- 20-25% less mass
Performance Improvements After Hot Water Extraction
- Easy to densify into pellets (high energy density saves on transportation costs)
- Increased structural stability (less likely to break and decreased hydrophilicity)
- For burning: increased Btu content and reduced ash content
- For pulp and paper: increased viscosity during pulping, improving energy efficiency