Regulating the hydrolysis of organic wastes by micro-aeration and effluent recirculation.
In this study, the effects of micro-aeration and liquid recirculation on the hydrolysis of vegetable and flower wastes during two-phase solid-liquid anaerobic digestion were assessed. To accomplish this, we evaluated the hydrolysis of five batches of waste that were treated under the following conditions: anaerobic, insufficient micro-aeration (aeration for 5 min every 24 h), and sufficient micro-aeration (aeration for 5 min every 12, 4 and 1h). Hydrolysis was found to depend on the level of micro-aeration. Specifically, insufficient micro-aeration led to unstable and decreased performance. Conversely, sufficient micro-aeration promoted the hydrolysis of easily biodegradable carbohydrates and proteins, but the microbial activity was later impaired by liquid recirculation using methanogenic effluent. The hydrolysis efficiency under anaerobic conditions was comparable to the efficiency observed under sufficient micro-aeration, while the cumulative TOC of the anaerobic batch was 1.4-2.4 times higher than that of the micro-aerated batches. In addition, liquid recirculation did not have a negative effect on the development of microbial activity under anaerobic conditions, which resulted in the lignocelluloses having a higher hydrolysis efficiency.
Zhu
Min
M
State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze River Water Environment, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China.
Lü
Fan
F
Hao
Li-Ping
LP
He
Pin-Jing
PJ
Shao
Li-Ming
LM
D000332:Aerobiosis; D000693:Anaerobiosis; D019149:Bioreactors; D005735:Garbage; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D009930:Organic Chemicals / Q000378:metabolism*; D010084:Oxidation-Reduction
D009930:Organic Chemicals