| Carbohydrate is a type of important substrate of anaerobic fermentation technique to produce methane.
Many complex organics such as straw are first hydrolyzed to soluble sugar solution, further to produce acid and methane.
The impact factors to the methanogenic features of sugar substrate were studied at high organic loading condition. The
accumulative biogas decreased above 10 000 mg COD/L organic loading in the anaerobic fermentation, when glucose used
as the sole carbon source, acidification occurred in the system caused the difficultly obtained stable methanogenic
conditions. The addition of sodium bicarbonate alkalinity was approved to be a quite effective strategy to ensuring the
methane production with sugar solution substrate at high organic loading. The initial alkalinity concentration of 600 mg
CaCO3/L could guarantee the methanogenic conditions at the organic loading of 8 000 mg COD/L, whereas in the alkalinity
concentration range of 1 500~3 300 mg CaCO3/L, the increase of alkalinity concentration had no significant effect on the
increase of methane production. Orthogonal test disclosed that the most important factors were followed by inoculums
proportion, initial alkalinity concentration and C/N. |
