Ministry of Education, Key Laboratory of Groundwater Cycle and Environment Evolution (China University of Geosciences (Beijing)), No. 29, Xueyuan Road, Beijing 100083, China.
Water Sci Technol. 2012;66(9):1900-7. doi: 10.2166/wst.2012.279.
To enhance the efficiency of nitrate removal from synthetic groundwater, wheat rice stone (WRS) and granular activated carbon (GAC) were employed as biofilm carriers for denitrification under different HRT (hydraulic retention time) and C/N ratios. Four different ratios of GAC to WRS (0, 0.5, 1.0, and 2.0) were investigated to determine the most appropriate ratio of GAC and WRS. The NO(3)(-)-N, NO(2)(-)-N, COD levels and pH of the effluent were also investigated under various HRT and C/N ratios. The results showed that the column at a GAC/WRS ratio of 1.0 performed best under a C/N ratio of 0.9 and an HRT of 8 h, with 99% nitrate being removed. In addition, little nitrite accumulation and chemical oxygen demand (COD) were observed in effluent under these conditions. These results demonstrated that, with no addition of phosphor in the influent, the nitrate removal efficiency can be enhanced by WRS because WRS can leach trace elements and phosphor to promote the growth of bacteria.
为了提高从合成地下水中去除硝酸盐的效率，采用小麦水稻石（WRS）和颗粒活性炭（GAC）作为生物膜载体，在不同的水力停留时间（HRT）和 C/N 比下进行反硝化。研究了四种不同的 GAC 与 WRS 比例（0、0.5、1.0 和 2.0），以确定 GAC 和 WRS 的最佳比例。还在不同的 HRT 和 C/N 比下研究了出水中的 NO(3)(-) -N、NO(2)(-) -N、COD 水平和 pH 值。结果表明，在 C/N 比为 0.9 和 HRT 为 8 h 时，GAC/WRS 比为 1.0 的柱效果最佳，去除了 99%的硝酸盐。此外，在这些条件下，出水中几乎没有亚硝酸盐积累和化学需氧量（COD）。这些结果表明，在没有向进水添加磷的情况下，WRS 可以提高硝酸盐去除效率，因为 WRS 可以浸出痕量元素和磷来促进细菌的生长。
