钢渣构造人工湿地运行初期无机氮转化特点研究 |
摘要点击 2211 全文点击 1897 投稿时间:2008-05-18 修订日期:2008-11-05 |
查看HTML全文
查看全文 查看/发表评论 下载PDF阅读器 |
中文关键词 钢渣 潜流湿地 氨氮型污水 硝氮型污水 反硝化 |
英文关键词 steel slag subsurface wetland ammonium-dominated wastewater nitrate-dominated wastewater denitrification |
|
中文摘要 |
以钢渣为主要基质构建小型潜流湿地,探索湿地运行初期对污水中低浓度无机氮的去除效果及氮转化特点.结果表明,钢渣湿地对氨氮型污水中总氮(TN)、氨氮(NH+4-N)和硝氮(NO-3-N)的去除速率分别是0.12、 0.07和0.10 g·(m2·d)-1,亚硝氮(NO-2-N)积累速率是0.04 g·(m2·d)-1;荧光原位杂交方法没有在钢渣基质上检测到硝化细菌,NH+4-N去除的主要途径是在高pH (>10)的水环境下挥发到上层土壤,由土壤层去除;钢渣湿地对硝氮型污水中TN的去除速率是0.23 g·(m2·d)-1,NO-3-N的去除速率是0.48 g·(m2·d)-1,NO-3-N在钢渣湿地内主要通过反硝化去除,反硝化过程中出现NO-2-N积累,积累速率为0.22 g·(m2·d)-1.钢渣湿地运行初期对硝氮型污水的处理能力高于氨氮型污水,钢渣可作为一种强化反硝化基质应用于NO-3-N的去除或其他组合工艺中. |
英文摘要 |
Lab-scale subsurface flow slag-wetlands were constructed to study the removal efficiency and transformation processes of low-concentration inorganic N during the start-up period. As for ammonium-dominated wastewater, the removal rates of total nitrogen (TN), ammonium nitrogen (NH+4-N), nitrate nitrogen (NO-3-N) and nitrite nitrogen (NO-2-N) were 0.12 g·(m2·d)-1, 0.07 g·(m2·d)-1, 0.10 g·(m2·d)-1 and 0.04 g·(m2·d)-1, respectively. Nitrifying bacteria was not detected by fluorescence in situ hybridization (FISH) on the slag. NH3 volatilization is the main contribution for N removal resulting from high pH (>10) and surface soil absorbed most of NH3. For nitrate-dominated wastewater, the removal rates of TN and NO-3-N were 0.23 g·(m2·d)-1 and 0.48 g·(m2·d)-1, and NO-2-N accumulated by 0.22 g·(m2·d)-1 during the process of denitrification. Removal efficiency of inorganic N for nitrate-dominated wastewater was higher than that for ammonium-dominated wastewater during the start-up period of slag-wetlands, so steel slag can be used as a substrate in constructed wetlands for extensive treatment of nitrate pollution. |