Department of Environmental Resources Engineering, College of Environmental Science and Forestry, State University of New York, 1 Forestry Dr., Syracuse, NY 13210, USA.
J Environ Manage. 2012 Nov 15;110:103-9. doi: 10.1016/j.jenvman.2012.06.009. Epub 2012 Jul 2.
Design considerations to enhance simultaneous partial nitrification and anammox in constructed wetlands are largely unknown. This study examined the effects of pH and seasonal temperature variation on simultaneous partial nitrification and anammox in two free-water surface wetlands. In order to enhance partial nitrification and inhibit nitrite oxidation, furnace slag was placed on the rooting substrate to maintain different pH levels in the wetland water. The wetlands were batch operated for dairy wastewater treatment under oxygen-limited conditions at a cycle time of 7 d. Fluorescence in situ hybridization analysis found that aerobic ammonium oxidizing bacteria and anammox bacteria accounted for 42-73% of the bacterial populations in the wetlands, which was the highest relative abundance of ammonium oxidizing and anammox bacteria in constructed wetlands enhancing simultaneous partial nitrification and anammox. The two wetlands removed total inorganic nitrogen efficiently, 3.36-3.38 g/m(2)/d in the warm season with water temperatures at 18.9-24.9 °C and 1.09-1.50 g/m(2)/d in the cool season at 13.8-18.9 °C. Plant uptake contributed 2-45% to the total inorganic nitrogen removal in the growing season. A seasonal temperature variation of more than 6 °C would affect simultaneous partial nitrification and anammox significantly. Significant pH effects were identified only when the temperatures were below 18.9 °C. Anammox was the limiting stage of simultaneous partial nitrification and anammox in the wetlands. Water pH should be controlled along with influent ammonium concentration and temperature to avoid toxicity of free ammonia to anammox bacteria.
强化人工湿地同步硝化反硝化的设计考虑因素在很大程度上尚不清楚。本研究考察了 pH 值和季节性温度变化对两种自由水面湿地同步硝化反硝化的影响。为了强化部分硝化作用和抑制亚硝酸盐氧化，在湿地水培基质中加入炉渣，以维持不同的 pH 值水平。在 7d 的周期时间内，在缺氧条件下对奶牛废水进行批量处理，湿地采用批处理运行。荧光原位杂交分析发现，好氧氨氧化菌和厌氧氨氧化菌在湿地细菌种群中占 42-73%，这是构建湿地强化同步硝化反硝化中氨氧化和厌氧氨氧化菌的最高相对丰度。两个湿地有效地去除了总无机氮，在温暖季节（水温为 18.9-24.9°C），总无机氮去除率为 3.36-3.38g/m(2)/d，在凉爽季节（水温为 13.8-18.9°C），总无机氮去除率为 1.09-1.50g/m(2)/d。在生长季节，植物吸收对总无机氮去除的贡献率为 2-45%。季节性温度变化超过 6°C 会显著影响同步硝化反硝化。只有当温度低于 18.9°C 时，才会发现显著的 pH 值影响。在湿地中，厌氧氨氧化是同步硝化反硝化的限制阶段。应控制水的 pH 值以及进水氨氮浓度和温度，以避免游离氨对厌氧氨氧化菌的毒性。
