人工快速渗滤系统脱氮机理试验研究

NITROGEN REMOVAL MECHANISM OF THE CONSTRUCTED RAPID INFILTRATION SYSTEM

为了探寻人工快速渗滤系统脱氮的机理,采用人工试验土柱模拟人工快速渗滤系统,通过监测不同高度出水中的氨氮、硝态氮和总氮的浓度,得到了其随高度的变化规律。试验结果表明:人工试验土柱中填料层0～1200mm段氨氮的去除率很高,约占总去除率95%,深度越浅氨氮降解效率越高,深度越大氨氮降解效率越低;填料层中900mm处,硝态氮达到最大值14.08～15.06mg·L-1,在兼氧段(900～1200mm)和厌氧段(1200～1500mm)硝态氮浓度下降仅10%左右;出水总氮浓度16.50～21.85mg·L-1,去除率为28.35%～29.78%。

In order to understand the nitrogen removal mechanism, the variation law of the ammonia, nitrate and total nitrogen concentration with height is obtained by monitoring their concentrations of the simulated soil column effluent from the different outlets instead of CRI system. The results demon- strated that the ammonia nitrogen removal rate is about 95% of the total one, in the section of 0-900 mm the infiltration media in the simulated soil column. The shallower its height, the higher the ammonia nitrogen removal rate is. The nitrate nitrogen concentration reaches the maximums, 14.08-15.06 mg· L^-1; In the facultative anaerobic（900-1200 mm） and anaerobic （1 200-1 500 mm） sections, the descent range of nitrate nitrogen concentration is 10% of its maximum, and the total nitrogen concentration of the effluent 16.50-21.85 mg·L^-1 , its removal rate is only 28.35%-29.78%.