Biogas Digester Hydraulic Retention Time Affects Oxygen Consumption Patterns and Greenhouse Gas Emissions after Application of Digestate to Soil

摘要: Knowledge about environmental impacts associated with the application of anaerobic digestion residue to agricultural land is interest owing rapid proliferation biogas plants worldwide. However, virtually no information exists concerning how soil-emitted NO affected by feedstock hydraulic retention time (HRT) in digester. Here, O planar optode technique was used visualize soil dynamics following surface digestates codigestion pig slurry and agro-industrial waste. We also isotopomer analysis determine production pathways, i.e., nitrification or denitrification. Two-dimensional images indicated that anoxic hypoxic conditions developed at 2.0- 1.5-cm depth for amended digestate produced 15-d (PO15) 30-d (PO30) time, respectively. Total emissions were significantly lower PO15 than PO30 due greater expansion zone, which enhanced reduction via complete cumulative CO not different between entire incubation period. During incubation, came from both denitrification soils. Increasing HRT digester appears induce significant emissions, but it unlikely affect pathways after soil.