Shiguan Yang

Vermicompost as an accelerator of methane production

The influences of different vermicompost concentrations of 8.33, 4.35 and 0.9%, respectively (based on TS), on the CH4 production, Specific Methanogenic Activities (SMAs) of the anaerobic sludge, pH and COD removal were investigated. A maximum cumulative CH4 production of 874 ml/L fermentation liquor was obtained from the experiment with vermicompost concentration of 8.33% which increased by 40.3% when compared with the control, and a maximum SMA of 295.9 mg COD CH4/g VS•d was achieved which increased by 45% relative to the control. The results also showed that vermicompost could enhance the COD removal and improve the buffering capacity of anaerobic digestion system.

Anaerobic batch co-digestion of Spartina alterniflora and potato

The potential of mesophilic anaerobic batch digestion for the treatment of Spartina alterniflora, an invasive species widely distributed along Chinese coastlines, through co-digestion with readily biodegradable organics has been assessed. The accumulative biogas yield from S. alterniflora alone was 251 ml/g Total Solid (TS) (at 35°C), at TS of 6%, co-digestion with 80% of S. alterniflora and 20% of potato representing 6% of TS, gave a biogas yield of 383 ml/g TS (at 35°C). This is an increase of 52.5% compared with that obtained from digestion of pure S. alterniflora. In conclusion, using readily biodegradable potato as co-substrate of S. alterniflora can increase its anaerobic digestibility and biogas yield.