Satoh Hisashi, Nakamura Yoshiyuki, Ono Hideki, Okabe Satoshi
Department of Environmental and Civil Engineering, Hachinohe Institute of Technology, 88-1 Ohbiraki, Myo, Hachinohe, Aomori 031-8501, Japan.
Biotechnol Bioeng. 2003 Sep 5;83(5):604-7. doi: 10.1002/bit.10717.
Simultaneous nitrification and denitrification (SND) was investigated in the single aeration tank of a municipal wastewater treatment plant. Microelectrode measurements and batch experiments were performed to test for the presence of SND. Microelectrodes recorded the presence of O(2) concentration gradients in individual activated sludge flocs. When the O(2) concentration in the bulk liquid was <45 microM, anoxic zones were detected within flocs with a larger diameter (approximately 3000 microm). The O(2) penetration depth in the floc was found to be dependent on the O(2) concentration in the bulk liquid. Nitrification was restricted to the oxic zones, whereas denitrification occurred mainly in the anoxic zones. The nitrification rate of the activated sludge increased with increasing O(2) concentration in the bulk liquid, up to 40 microM, and remained constant thereafter. SND was observed in the aerated activated sludge when O(2) concentration was in the range of 10 to 35 microM.
在一座城市污水处理厂的单一曝气池中对同步硝化反硝化（SND）进行了研究。进行了微电极测量和批次实验以检测SND的存在。微电极记录了单个活性污泥絮体中O(2)浓度梯度的存在。当主体液体中的O(2)浓度<45微摩尔时，在直径较大（约3000微米）的絮体中检测到缺氧区。发现絮体中O(2)的穿透深度取决于主体液体中的O(2)浓度。硝化作用局限于好氧区，而反硝化作用主要发生在缺氧区。活性污泥的硝化速率随着主体液体中O(2)浓度的增加而增加，直至40微摩尔，此后保持恒定。当O(2)浓度在10至35微摩尔范围内时，在曝气活性污泥中观察到了同步硝化反硝化。
