Irizar I, Suescun J, Plaza F, Larrea L
Environmental Engineering Section, CEIT, 20018 San Sebastian, Spain.
Water Sci Technol. 2003;48(11-12):429-36.
The potential and limits of different configurations of the BioDenitro-alternating process to suit the various design cases that can arise depending on the wastewater characteristics, space necessary and effluent nitrogen requirements were analysed through simulations of the activated sludge model No. 2. The first analysis involved the combination in one cycle of the main phase in the alternating reactors with an aerated phase having the two reactors in aerobic conditions and/or a hydraulic phase using the flow only in the anoxic reactor. This option has been found to have a very high potential for cases with strict requirements concerning effluent total nitrogen, but limited when the requirements are low effluent NH4-N, relatively high effluent total nitrogen and minimum solids and hydraulic retention times. When the latter conditions have to be fulfilled the incorporation of a post-aeration reactor to the alternating reactor was found to be very effective. In addition the configuration is very flexible because multiple combinations of post-aeration reactor volumes and in the duration of the different phases in the alternating reactors can be selected to achieve effluent nitrogen requirements. This flexibility is limited to the use of moderate values in the post-aeration reactor volumes and in the duration of the aerated phase. An experimental trial of the latter configuration was carried out and demonstrated its operational simplicity by achieving the desired nitrogen requirements in the effluent simply by changing the duration of the aerated phase for a given post-aeration reactor volume. From the experimental results an enhanced simultaneous nitrification-denitrification at the start of aeration in the alternating reactors was found and the ASM2 model was shown to have a satisfactory predictive capacity.
通过对活性污泥2号模型的模拟，分析了BioDenitro交替工艺不同配置的潜力和局限性，以适应根据废水特性、所需空间和出水氮要求可能出现的各种设计情况。首次分析涉及交替反应器中主阶段与曝气阶段在一个周期内的组合，曝气阶段使两个反应器处于好氧条件，和/或水力阶段仅使用缺氧反应器中的水流。已发现此选项对于对出水总氮有严格要求的情况具有很高的潜力，但对于出水NH4-N要求低、出水总氮相对较高且固体和水力停留时间最短的情况则有限。当必须满足后一种条件时，发现将后置曝气反应器并入交替反应器非常有效。此外，该配置非常灵活，因为可以选择后置曝气反应器体积和交替反应器中不同阶段持续时间的多种组合来实现出水氮要求。这种灵活性仅限于在后置曝气反应器体积和曝气阶段持续时间中使用中等值。对后一种配置进行了试验，通过在给定的后置曝气反应器体积下仅改变曝气阶段的持续时间，实现了出水中所需的氮要求，证明了其操作的简便性。从实验结果中发现，交替反应器曝气开始时同时硝化反硝化作用增强，并且活性污泥2号模型显示出令人满意的预测能力。
