Jiangsu Key Laboratory of Anaerobic Biotechnology, School of Environmental and Civil Engineering, Jiangnan University, Wuxi 214122, Jiangsu Province, PR China; Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment, Suzhou University of Science and Technology, Suzhou 215009, PR China.
Jiangsu Key Laboratory of Anaerobic Biotechnology, School of Environmental and Civil Engineering, Jiangnan University, Wuxi 214122, Jiangsu Province, PR China.
J Hazard Mater. 2019 Mar 5;365:912-920. doi: 10.1016/j.jhazmat.2018.11.082. Epub 2018 Nov 22.
A novel strategy of liquid fermentation using anaerobic dynamic membrane reactor (AnDMBR) was proposed to enhance volatile fatty acids (VFAs) production from sewage sludge. Results indicated that liquid sludge fermentation in AnDMBR had the potential in commercial VFAs production. VFAs productivity and concentration as well as substrate conversion rate could reach as high as 7.8 kg VFA-COD/m d, 60 g/L and 0.38 kg VFA-COD/kg VS, respectively. Moreover, dynamic membrane was stably operated for approximately 70 days. During the operational period, membrane flux was increased from 6.25 to 25 L/m d and only once online membrane cleaning was implemented. Results of microbial analyses showed bacterial richness and evenness in AnDMBR were increased by membrane separation and organic loading rate (OLR) increase, but reduced by excessive OLR, which should led the variations in the performances of AnDMBR. Furthermore, the necessity of liquid sludge fermentation for VFAs production was further confirmed by economic assessment and the bioavailability analysis of the residual solids in pretreated sludge. The residual solid was proved to be not conducive to enhance VFAs yield. Conversely, the energy consumption for VFAs production could be reduced from over 100 to below 20 kwh/kg VFAs by avoiding the "useless" residual solids entering into fermenters.
采用厌氧动态膜生物反应器（AnDMBR）的新型液体发酵策略被提出，以提高污水污泥中挥发性脂肪酸（VFAs）的产量。结果表明，AnDMBR 中的液体污泥发酵在商业 VFAs 生产中具有潜力。VFAs 生产力、浓度和底物转化率分别高达 7.8 kg VFA-COD/m d、60 g/L 和 0.38 kg VFA-COD/kg VS。此外，动态膜稳定运行了大约 70 天。在运行期间，膜通量从 6.25 增加到 25 L/m d，仅进行了一次在线膜清洗。微生物分析结果表明，膜分离和有机负荷率（OLR）的增加增加了 AnDMBR 中的细菌丰富度和均匀度，但过高的 OLR 会降低其性能，这应该导致了 AnDMBR 性能的变化。此外，通过经济评估和预处理污泥中剩余固体的生物可利用性分析，进一步证实了液体污泥发酵对 VFAs 生产的必要性。剩余固体被证明不利于提高 VFAs 的产量。相反，通过避免“无用”的剩余固体进入发酵罐，可以将 VFAs 生产的能耗从超过 100 kWh/kg VFAs 降低到 20 kWh/kg VFAs 以下。
