Faculty of Engineering and Physical Sciences, University of Southampton, UK.
Faculty of Engineering and Physical Sciences, University of Southampton, UK; School of Civil Engineering, University of Birmingham, UK; National Buried Infrastructure Facility, University of Birmingham, UK.
Waste Manag. 2020 Apr 15;107:101-112. doi: 10.1016/j.wasman.2020.03.016. Epub 2020 Apr 22.
Changing waste management practice, introduction of new technologies, and population demographics and behaviour will impact on both quantity and composition of future waste streams. Laboratory-scale anaerobic digestion of the mechanically-separated organic fraction of municipal solid waste (ms-OFMSW) was carried out at relatively low organic loading rates (OLR), and results analysed using an energy modelling tool. Thermophilic operation with water addition and liquor recycle was compared to co-digestion with dilution water replaced by sewage sludge digestate (SSD); thermophilic and mesophilic mono-digestion were also tested at low OLR. All thermophilic conditions showed stable operation, with specific methane production (SMP) from 0.203 to 0.296 m CH kg volatile solids (VS). SSD addition increased biogas production by ~20% and there was evidence of further hydrolysis and degradation of the SSD. Long-term operation at 1 kg VS m day had no adverse effect except in mesophilic conditions where SMP was lower at 0.256 m CH kg VS and stability was reduced, especially during OLR increases. This was probably due to low total ammonia nitrogen, which stabilised at ~0.2 g N kg and limited the buffering capacity. Energy analysis showed thermophilic operation at OLR 2 g VS L day gave 42% of the theoretical methane potential and 38% of the higher heating value, reducing to 37% and 34% respectively in mesophilic conditions. Scenario modelling indicated that under low ms-OFMSW load even an energy-depleted co-substrate such as SSD could contribute to the energy balance, and would be a better diluent than water due to its nutrient and buffering capacity.
改变废物管理实践、引入新技术以及人口统计和行为将影响未来废物流的数量和组成。在相对较低的有机负荷率 (OLR) 下，对城市固体废物 (ms-OFMSW) 的机械分离有机部分进行了实验室规模的厌氧消化，并使用能源建模工具分析了结果。与用污水污泥消化物 (SSD) 替代稀释水的共消化相比，添加水和液体再循环的高温操作与高温和中温单消化进行了比较；在低 OLR 下也进行了测试。所有高温条件均表现出稳定的运行，特定甲烷产量 (SMP) 为 0.203 至 0.296 m CH kg 挥发性固体 (VS)。添加 SSD 可使沼气产量增加约 20%，并且有证据表明 SSD 进一步水解和降解。除了在中温条件下，SMP 为 0.256 m CH kg VS 且稳定性降低外，在 1 kg VS m day 下的长期运行没有不良影响，尤其是在 OLR 增加期间。这可能是由于总氨氮较低，其稳定在约 0.2 g N kg 并限制了缓冲能力。能量分析表明，在 OLR 2 g VS L day 下进行高温操作可获得 42%的理论甲烷潜能和 38%的高热值，在中温条件下分别降低到 37%和 34%。情景模拟表明，在 ms-OFMSW 负载较低的情况下，即使是能源耗尽的共底物，如 SSD，也可以为能量平衡做出贡献，并且由于其营养成分和缓冲能力，它将是比水更好的稀释剂。
