State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.
State Key Joint Laboratory of Environment Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China.
Bioresour Technol. 2019 Nov;292:121895. doi: 10.1016/j.biortech.2019.121895. Epub 2019 Jul 26.
Polyhydroxyalkanoates (PHA) production from fermented thermal-hydrolyzed sludge was conducted by mixed microbial cultures (MMCs) in the study. An MMC enriched in the species Brachymonas_denitrificans (60.18%) was selected under an aerobic feast/famine regime, which is capable of denitrification and accumulating PHA. To take advantage of the PHA-storing denitrifiers, an aerobic-feast/anoxic-famine regime was applied to integrate culture selection with denitrification. The results showed that cultures enriched under the regime exhibited a PHA storage capacity with PHA yield on VFA of 0.47 gCOD/gCOD and well denitrification performance achieving nitrate removal of 98%. Moreover, the aerobic-feast/anoxic-famine regime could originate a comparable maximum PHA content to the complete aerobic feast/famine regime (49.7 wt% versus. 47.1 wt%, respectively), yet reduce aeration energy input by 79% in the culture selection process. Finally, this study investigated the accumulation of nitrite and nitrous oxide during PHA based denitrification and the feasibility of integrating the process with wastewater treatment.
聚羟基烷酸酯（PHA）的生产是通过混合微生物培养（MMC）在研究中从发酵的热水解污泥进行的。在好氧饱食/饥饿条件下，选择了一种富含脱氮假单胞菌（60.18%）的 MMC，该菌能够进行脱氮和积累 PHA。为了利用储存 PHA 的脱氮菌，采用好氧饱食/缺氧饥饿的方式将培养物选择与脱氮相结合。结果表明，在该条件下富集的培养物具有 PHA 储存能力，VFA 上的 PHA 产率为 0.47 gCOD/gCOD，并且具有良好的脱氮性能，可实现 98%的硝酸盐去除率。此外，好氧饱食/缺氧饥饿方式可以在培养物选择过程中减少 79%的曝气能耗，同时产生与完全好氧饱食/饥饿方式相当的最大 PHA 含量（分别为 49.7%wt 和 47.1%wt）。最后，本研究考察了基于 PHA 的脱氮过程中亚硝酸盐和氧化亚氮的积累情况，并探讨了将该过程与废水处理相结合的可行性。
