Effect of Walnut Shell Biochar on Dry Anaerobic Fermentation

PurposeTo improve the gas production efficiency of dry anaerobic fermentation of cow manure and explore the effect of biochar on it.

MethodsThe biochar made from walnut shell under different temperature gradients was added into the dry fermentation system. The amount of biochar was 4% of the total solid (TS), the amount of total dry matter in fermentation tank accounts for 25% of total fermentation quality, and the inoculation rate was 30% of the total fermentation weight. The fermentation experiment was carried out under the medium temperature (37±1)℃, and the biochar and fermentation broth were scanned by electron microscope.

Results600H group played a good role in promoting VS methane production, which was (183.46±2.93) mL/g, 30.52% higher than that of the control group. Election microscope showed that microbial community aggregated in 500H group, 600H group and control qroup.

ConclusionThe biochar prepared at relatively low temperature is not conducive to dry fermentation, and the biochar of 500H group and 600H group is conducive to dry fermentation. This study provides support for the research of adding biochar in dry fermentation.