Ho C M, Tseng S K, Chang Y J
Graduate Institute of Environmental Engineering, National Taiwan University, 71 Chou-Shan Road Taipei, Taiwan.
Lett Appl Microbiol. 2002;35(6):481-5. doi: 10.1046/j.1472-765x.2002.01225.x.
To develop a laboratory-scale autotrophic membrane-immobilized biofilm reactor to remove nitrogen from drinking water.
A polyvinyl alcohol (PVA) immobilized biofilm, attached to the surface of a silicone tube, was used as the basis of a bioreactor for simultaneous nitrification and denitrification of water. The bioreactor was aerated with air to supply oxygen for nitrification. Pure hydrogen was supplied to the silicone tube and diffused through the membrane wall to feed the biofilm for autotrophic denitrification. The bioreactor was effective for the simultaneous nitrification and denitrification of water after a short period of acclimation, while the biofilm exhibited good resistance to the inhibition of denitrification by dissolved oxygen; the denitrification rate decreased by only 8% as the dissolved oxygen increased from 2 mg l(-1) to saturation.
By using PVA crosslinked with sodium nitrate to entrap nitrifying and denitrifying sludge on the surface of a silicone tube, a novel bioreactor for simultaneous nitrification and denitrification was developed. In addition to performing as an immobilizing agent to strengthen the biofilm, PVA protected the denitrifying microorganisms to reduce the inhibition by dissolved oxygen under aerobic condition. Therefore, nitrification and denitrification occurred simultaneously within the biofilm. Furthermore, the immobilization technique shortened the acclimation period of the bioreactor.
The described space saving and simple to operate bioreactor for nitrogen removal performed autotrophic denitrification to solve the problem of residual carbon in heterotrophic denitrification, and thus is suitable for removing nitrogen from drinking water.
开发一种实验室规模的自养膜固定化生物膜反应器，用于去除饮用水中的氮。
以附着在硅胶管表面的聚乙烯醇（PVA）固定化生物膜为基础构建生物反应器，用于水的同步硝化和反硝化。通过曝气向生物反应器供应氧气以进行硝化作用。向硅胶管供应纯氢气，氢气透过膜壁扩散以滋养生物膜进行自养反硝化。经过短时间驯化后，该生物反应器对水的同步硝化和反硝化有效，同时生物膜对溶解氧抑制反硝化表现出良好抗性；当溶解氧从2 mg l(-1)增加到饱和时，反硝化速率仅下降8%。
通过使用与硝酸钠交联的PVA将硝化和反硝化污泥截留在硅胶管表面，开发了一种新型的同步硝化反硝化生物反应器。PVA除了作为固定剂强化生物膜外，还保护反硝化微生物以减少有氧条件下溶解氧的抑制作用。因此，生物膜内同时发生硝化和反硝化。此外，固定化技术缩短了生物反应器的驯化期。
所描述的用于脱氮的节省空间且操作简单的生物反应器进行自养反硝化，解决了异养反硝化中残留碳的问题，因此适用于饮用水脱氮。
