Table 2 Properties of raw biomass, torrefied briquettes, and coal
Properties | Raw biomass | Torrefied briquettes | Coal |
|---|---|---|---|
Moisture content (MC) | High (> 15 wt%) | Low (< 5%) | Low (< 5%) |
Volatile matter (VM) | High (65–88 wt%) | Low (35–45%) | Low (0.9–50%) |
Fixed carbon (FC) | Low (0.5–20 wt%) | Moderate (20–45%) | High (46–92%) |
Carbon | 39–50 wt% | 45–68 wt% | 64–92 wt% |
Oxygen | 37–50 wt% | 11–45 wt% | 1–25 wt% |
Atomic O/C ratio | 0.4–0.8 | 0.1–0.7 | – |
Atomic H/C ratio | 1.2–2.0 | 0.7–1.6 | – |
Volumetric energy density (GJ/m3) | 2.0–3.0 | 15.0–18.7 | 18.4–23.8 |
Handling and logistics | Low bulk density | High bulk density | Low handling requirements |
CO2 emission | Carbon-neutral | Carbon-neutral | Fossil Fuel |
Co-Firing Ratio with Coal | Low co-firing ratios due to low bulk density | Up to 50% or more | N/A |
Heating value | 9–12 MJ/kg | 15–24 MJ/kg | 23–35 MJ/kg |
Dust explosibility | Average | Limited | Limited |
Hydroscopic properties | Hydrophilic | Hydrophobic | Hydrophobic |
Biological degradation | Yes | No | No |
Transport cost | High | Low | Low |