Muller E B, Stouthamer A H, van Verseveld H W
Department of Microbiology, Biological Laboratory, Vrije Universiteit, Amsterdam, The Netherlands.
Biodegradation. 1995;6(4):339-49. doi: 10.1007/BF00695264.
The ammonia oxidation rate by sewage sludge was determined as a function of the dissolved oxygen tension. Samples of sludge were taken from a domestic waste water treatment pilot plant in which sludge was completely retained by membrane filtration. The samples were subcultured chemolithotrophically in recycling reactors. The gas supplied was a mixture of pure argon and oxygen. The KO2 for ammonia oxidation was estimated to be 0.97 (+/- 0.16) kPa dissolved oxygen. Together with ammonia oxidation and oxygen consumption, dinitrogen gas was produced. So, aerobic denitrification occurred. At dissolved oxygen tensions of 1.25 kPa and higher, the dinitrogen production rate (per N-mole) equalled 20% of the ammonia oxidation rate. This proportion was even 58% at 0.3 kPa dissolved oxygen. At 0.15 kPa dissolved oxygen, however, nitrification hardly proceeded, while dinitrogen production soon stopped. Most likely, a nitrifier concomitantly oxidized ammonia and reduced nitrite to dinitrogen.
测定了污水污泥的氨氧化速率与溶解氧张力的函数关系。污泥样本取自一个生活污水处理试验厂，在该厂中污泥通过膜过滤完全截留。样本在循环反应器中进行化能自养继代培养。供应的气体是纯氩气和氧气的混合物。氨氧化的半饱和常数（KO2）估计为0.97（±0.16）kPa溶解氧。伴随着氨氧化和氧气消耗，产生了氮气。因此，发生了好氧反硝化作用。在溶解氧张力为1.25 kPa及更高时，氮气产生速率（每N摩尔）等于氨氧化速率的20%。在溶解氧为0.3 kPa时，这一比例甚至达到58%。然而，在溶解氧为0.15 kPa时，硝化作用几乎不进行，而氮气产生很快停止。很可能是一种硝化细菌同时将氨氧化并将亚硝酸盐还原为氮气。
