Table 7.
Performance of anaerobic digestion systems with varying types of biochar
| Biochar materials | Pyrolysis temperature | Feedstock | Biochar concentration | Anaerobic digestion performance | References |
|---|---|---|---|---|---|
| Wheat straw, fruitwood, and chicken manure | 350, 450, 550 °C | Chicken manure | 5% | Enhanced methane production by 69% at 550 °C | Pan et al. (2019) |
| Manure | 350 °C | Air-dried manure | 10 g L−1 | Diminished lag phase and enhanced methane yield by 35.71% | Jang et al. (2018) |
| Fruitwoods | 800 °C | Food waste | 0.25–2.5 g per g total solids | Lowered lag phase by 36.3–54.0%; inoculum to substrate ratio at 0.8–2 improved the maximum methane generation aspect by 100–275%; Enhanced organic matter degradation | Cai et al. (2016) |
| Pine sawdust | 650 °C | Food waste | 8.3–33.3 g L−1 | Declined lag phase by 36–41%; Increased hydrogen and methane yield by 31% and 10%, respectively; Increased volatile fatty acid consumption | Sunyoto et al. (2016) |
| Forest waste | 450 °C | Sludge | 0.5–12.0 g per g total solids | 0.8 and 3.7 g per g VS improved methane generation by 192–61% during the first 16 d of digestion | Cimon et al. (2020) |
| Wood-pellets mixed with timber waste | 800 °C | Poultry litter | 100% poultry litter total solids | Decreased lag phase by 41%; Improved maximum daily methane generation by 136% | Indren et al. (2020) |
| Rice straw | 260 °C | Dead pig carcass | 2–10 g L−1 | Improved biogas yields up to 61–91% | Xu et al. (2018) |
Biochar additives derived from a variety of biomass sources have the potential to increase biogas production and reduce the lag time required to reach the peak of methane production during the anaerobic digestion process. The optimal dosage may be 10 g L−1 (w/w) of substrates