多级接触氧化工艺脱氮效果及不同运行方式的对比研究

重点考察了中试规模的多级接触氧化工艺处理不同浓度养鸡厂污水的脱氮效果,对接触氧化槽中的固定填料进行取样测量附着污泥的反硝化速率,发现好氧环境的填料表面污泥存在一定的反硝化性能,证明本工艺中存在同步硝化反硝化现象。通过分段进水以改善碳源不足、通过2#槽间歇曝气以强化缺氧环境,结果表明,缺氧环境不足是脱氮效果的主要限制因素,碳源不足对脱氮也有较大的负面影响。通过分析确定了本工艺的最佳运行方式为2#槽间歇曝气并联运行,当进水总氮质量浓度为203～408 mg/L时,其总氮去除率在81%左右,比最初的串联连续曝气方式时的总氮去除率提高37.9个百分点。

RESEARCH ON NITROGEN REMOVAL OF MULTI-LEVEL CONTACT OXIDATION PROCESS AND CONTRAST OF DIFFERENT OPERATION METHODS

The nitrogen removal of a pilot-scale multi-level contact oxidation reactor in the treatment of diluted chicken manure wastewater was investigated.The results showed that about 50% of total nitrogen was removed when the total nitrogen concentration of influent was between 203 mg/L and 408 mg/L.Denitrification rate of sludge on the surface of fixed carriers was tested and there was simultaneous nitrification and denitrification process in the reactor.Step-feed was used for improve of carbon source and intermittent aeration of contact oxidation tank 2# was used for increase of anoxic environment.The results showed lack of anoxic environment was the main limit factor of nitrogen removal and lack of carbon source also affected.Intermittent aeration of contact oxidation tank 2# and step-feed was the best operation method in our research,total nitrogen removal efficiency of which was about 81% when total nitrogen concentration of influent was between 203 mg/L to 408 mg/L,which was 37.9% higher than initial series normal aeration process.