State Key Laboratory of Separation Membranes and Membrane Processes, Tianjin Polytechnic University, Tianjin, 300387, China.
School of Environmental and Chemical Engineering, Tianjin Polytechnic University, Tianjin, 300387, China.
Environ Sci Pollut Res Int. 2018 Jan;25(1):749-757. doi: 10.1007/s11356-017-0457-5. Epub 2017 Oct 23.
In order to realize the rapid start-up of upflow anaerobic sludge blanket (UASB) reactor, the iron ion in different valence state was added to UASB. The results indicated that the start-up time of R3 (FeCl) was 48 h faster than that of R2 (zero-valent iron (ZVI)). It was because the FeCl could rapidly promote granulation of sludge as a flocculant. However, ZVI released Fe through corrosion slowly, and then the Fe increased start-up speed by enhancing enzyme activity and enriching methanogens. In addition, the ZVI and FeCl could promote hydrolysis acidification and strengthen the decomposition of long-chain fatty acids. The detection of iron ions showed that iron ions mainly existed in the sludge. Because the high concentration of Fe could inhibit anaerobic bacteria activity, excess Fe could be changed into iron hydroxide precipitation to hinder the mass transfer process of anaerobic bacteria under the alkaline condition. The FeCl was suitable to be added at the initial stage of UASB start-up, and the ZVI was more fitted to be used in the middle stage of reactor start-up to improve the redox ability.
为实现上流式厌氧污泥床（UASB）反应器的快速启动，向 UASB 中投加不同价态的铁离子。结果表明，R3（FeCl）的启动时间比 R2（零价铁（ZVI））快 48 h。这是因为 FeCl 可以作为絮凝剂快速促进污泥的颗粒化。然而，ZVI 通过腐蚀缓慢释放 Fe，然后通过增强酶活性和富集产甲烷菌来提高启动速度。此外，ZVI 和 FeCl 可以促进水解酸化，加强长链脂肪酸的分解。铁离子的检测表明，铁离子主要存在于污泥中。由于高浓度的 Fe 会抑制厌氧细菌的活性，过量的 Fe 可以转化为氢氧化铁沉淀，在碱性条件下阻碍厌氧细菌的传质过程。FeCl 适合在 UASB 启动的初始阶段添加，而 ZVI 更适合在反应器启动的中期使用，以提高氧化还原能力。
