鸡粪沼渣联合好氧堆肥基质降解与气体排放研究

Substrate Degradation and Gases Emission during Co-composting of Chicken Manure Digestion

利用好氧堆肥反应器系统开展鸡粪沼渣联合好氧堆肥试验,进行物理、化学、生物学指标和甲烷(CH_4)、氨气(NH_3)及氧化亚氮(N_2O)等排放气体的多元动态表征,并开展主要排放气体与堆体氧浓度和温度相关性分析。研究结果表明,通过合理物料配比、适度供氧的联合好氧堆肥可更有效地实现鸡粪沼渣安全、优质资源化利用。鸡粪沼渣联合好氧堆肥过程中,物理、化学、生物学指标动态变化具有良好的动态对应关系,纤维素类物质的降解主要集中在反应中后期。堆肥过程中CH_4与堆体氧浓度和温度均呈现良好的负相关关系,NH_3和N_2O与温度均呈正相关关系;可通过控制堆体氧浓度和温度调控气体排放。综上,基于多元参数表征、相关性分析可为鸡粪沼渣联合好氧堆肥工艺优化提供理论和方法学支撑。

A laboratory scale experiment of chicken manure digestion co-composting was carried out using a reactor system with oxygen monitoring and feedback control. The physioehemical indexes, including temperature, oxygen concentration, volatile solid content （VS） , moisture, C/N, pH value, EC, cellulose, hemicellulose, lignin, biological index, and main gas emissions （CH4, NH3 and N2O） were monitored and analyzed, respectively. Physical, chemical and biological indicators presented a good dynamic corresponding relationship, and the degradation of cellulose materials mainly appeared at the middle and later periods of aerobic eo-composting. Temperature and oxygen concentration had an effect on gas emissions： high temperature promoted the emissions of NH3 and N2O with a significantly positive correlation （ r = 0. 378 ; r = 0. 695 ） , high temperature and oxygen concentration decreased the emission of CH4 with a significantly negative correlation （r = -0. 470; r = -0. 494 ）. Gas emissions can be controlled through adjusting the levels of composing oxygen concentration and temperature. Multi- parameters characterization and correlation analyses can provide theoretical and methodological basis for process optimization of chicken manure and digestion co-composting. However, characterization and the coordination mechanism should be explored in depth on fermentation performance and gas emissions combining with comprehensive multi-indexes during and digestion co-composting in future studies.