Kuai L, Verstraete W
Laboratory of Microbial Ecology, Department of Biochemistry and Microbial Technology, State University of Ghent, 9000 Ghent, Belgium.
Appl Environ Microbiol. 1998 Nov;64(11):4500-6. doi: 10.1128/AEM.64.11.4500-4506.1998.
The present lab-scale research reveals the potential of implementation of an oxygen-limited autotrophic nitrification-denitrification (OLAND) system with normal nitrifying sludge as the biocatalyst for the removal of nitrogen from nitrogen-rich wastewater in one step. In a sequential batch reactor, synthetic wastewater containing 1 g of NH4+-N liter-1 and minerals was treated. Oxygen supply to the reactor was double-controlled with a pH controller and a timer. At a volumetric loading rate (Bv) of 0. 13 g of NH4+-N liter-1 day-1, about 22% of the fed NH4+-N was converted to NO2--N or NO3--N, 38% remained as NH4+-N, and the other 40% was removed mainly as N2. The specific removal rate of nitrogen was on the order of 50 mg of N liter-1 day-1, corresponding to 16 mg of N g of volatile suspended solids-1 day-1. The microorganisms which catalyzed the OLAND process are assumed to be normal nitrifiers dominated by ammonium oxidizers. The loss of nitrogen in the OLAND system is presumed to occur via the oxidation of NH4+ to N2 with NO2- as the electron acceptor. Hydroxylamine stimulated the removal of NH4+ and NO2-. Hydroxylamine oxidoreductase (HAO) or an HAO-related enzyme might be responsible for the loss of nitrogen.
目前的实验室规模研究揭示了以普通硝化污泥作为生物催化剂实施限氧自养硝化反硝化（OLAND）系统一步去除富氮废水中氮的潜力。在序批式反应器中，处理了含有1 g NH₄⁺-N/L和矿物质的合成废水。通过pH控制器和定时器对反应器的氧气供应进行双重控制。在体积负荷率（Bv）为0.13 g NH₄⁺-N/L·天⁻¹时，约22%的进水NH₄⁺-N转化为NO₂⁻-N或NO₃⁻-N，38%仍以NH₄⁺-N形式存在，另外40%主要以N₂形式去除。氮的比去除率约为50 mg N/L·天⁻¹，相当于16 mg N/g挥发性悬浮固体·天⁻¹。催化OLAND过程的微生物被认为是以铵氧化菌为主的普通硝化菌。OLAND系统中氮的损失推测是通过以NO₂⁻为电子受体将NH₄⁺氧化为N₂而发生的。羟胺促进了NH₄⁺和NO₂⁻的去除。羟胺氧化还原酶（HAO）或与HAO相关的酶可能是氮损失的原因。
