Department of Chemical Engineering, Escola d'Enginyeria, Universitat Autònoma de Barcelona, Spain.
Environ Sci Technol. 2010 Dec 1;44(23):8930-5. doi: 10.1021/es1019405. Epub 2010 Nov 4.
A ratio control strategy was implemented in a continuous granular airlift reactor to achieve and maintain 100% partial nitrification to nitrite (i.e., full nitritation). The control strategy was designed to maintain a constant ratio between the dissolved oxygen (DO) and the total ammonia nitrogen (TAN) concentrations (DO/TAN concentration ratio) in the reactor bulk liquid. The experimental results demonstrated the feasibility of full nitritation of a high-strength ammonium wastewater with a granular reactor operating in continuous mode, when implementing a suitable control strategy. The effect of the DO/TAN concentration ratio on partial nitrification was fast and reversible, upon switching from complete to partial nitrification, despite the presence of nitrite-oxidizing bacteria (NOB) in the granule. Even at a DO concentration as high as 7 mg of O(2) L(-1), full nitritation was obtained, decoupling the achievement of partial nitrification in continuous granular reactors from low DO concentrations. Inhibition of NOB by free ammonia was found to contribute poorly to the achievement of partial nitrification. An extremely high volumetric nitrogen loading rate was achieved (6.1 g of N L(-1) day(-1) at 30 °C), demonstrating that very compact reactors are applicable to nitrogen removal via nitrite.
采用一种比值控制策略在连续颗粒气升式反应器中实现并维持 100%亚硝态氮硝化（即完全亚硝化）。该控制策略旨在维持反应器液相中溶解氧（DO）和总氨氮（TAN）浓度之间的恒定比值（DO/TAN 浓度比）。实验结果表明，当采用合适的控制策略时，采用连续模式运行的颗粒反应器可以实现高强度氨氮废水的完全亚硝化。尽管颗粒中存在亚硝酸盐氧化菌（NOB），但 DO/TAN 浓度比对部分硝化的影响是快速且可逆的，从完全硝化切换到部分硝化时也是如此。即使 DO 浓度高达 7mg O2/L（-1），也能获得完全的亚硝化，从而将连续颗粒反应器中部分硝化的实现与低 DO 浓度脱钩。发现游离氨对亚硝化的抑制作用很差。实现了极高的容积氮负荷率（30°C 时为 6.1g N/L·d），这表明非常紧凑的反应器适用于通过亚硝酸盐进行脱氮。
