College of Life and Environmental Sciences, Guilin University of Electronic Technology, Guilin, 541004, China.
College of Life and Environmental Sciences, Guilin University of Electronic Technology, Guilin, 541004, China; State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China.
Chemosphere. 2022 Sep;303(Pt 1):134875. doi: 10.1016/j.chemosphere.2022.134875. Epub 2022 May 7.
CO is a proven pH regulator in hydrogen-based membrane biofilm reactor (H-MBfR) but how its pressure regulates microbial competition in this system remains unclear. This work evaluates the CO pressure dependent system performance, CO allocation, microbial structure and activity of CO source H-MBfR. The optimum system performance was reached at the CO pressure of 0.008 MPa, and this pressure enabled 0.18 g C/(m·d) of dissolved inorganic carbon (DIC) allocated to denitrifying bacteria (DNB) for carbon source anabolism and denitrification-related proton compensation, while inducing a bulk liquid pH (pH 7.4) in favor of DNB activity by remaining 0.21 g C/(m·d) of DIC as pH buffer. Increasing CO pressure from 0.008 to 0.016 MPa caused the markedly changed DNB composition, and the diminished DNB population was accompanied by the enrichment of sulfate-reducing bacteria (SRB). A high CO pressure of 0.016 MPa was estimated to induce the enhanced SRB activity and weakened DNB activity.
CO 是氢基膜生物膜反应器（H-MBfR）中一种经过验证的 pH 调节剂，但 CO 压力如何调节该系统中的微生物竞争尚不清楚。本工作评估了 CO 压力对系统性能、CO 分配、微生物结构和 CO 源 H-MBfR 活性的影响。在 CO 压力为 0.008 MPa 时达到最佳系统性能，该压力使 0.18 g C/(m·d)溶解无机碳 (DIC) 分配给反硝化细菌 (DNB) 用于碳源合成代谢和与反硝化相关的质子补偿，同时通过剩余 0.21 g C/(m·d) DIC 作为 pH 缓冲液将主体液体 pH（pH 7.4）维持在有利于 DNB 活性的水平。将 CO 压力从 0.008 MPa 增加到 0.016 MPa 会导致 DNB 组成发生明显变化，DNB 种群减少伴随着硫酸盐还原菌（SRB）的富集。估计 0.016 MPa 的高 CO 压力会导致增强的 SRB 活性和减弱的 DNB 活性。
