【摘要】 针对水平潜流湿地脱氮过程中后端碳源不足导致反硝化脱氮效果不佳的问题,对湿地植物香蒲采用简单处理、酸热处理和碱热处理这3种预处理,探讨香蒲在不同预处理条件下静态释放规律和反硝化特性,基于碳源稳定释放特性及反硝化特性优选碱热处理香蒲作为人工湿地实验系统补给碳源,研究其对水平潜流人工湿地脱氮的强化效果.结果表明,香蒲不同预处理方式导致乙酸释放存在差异,造成碳源静态释放量存在明显差异,3种香蒲处理方式的平均COD释放量为碱热处理(89. 57 mg·L-1)>酸热处理(67. 27 mg·L-1)>简单处理(54. 45 mg·L-1).碱热处理香蒲硝氮去除率为75. 2%,明显高于酸热处理(67. 2%)和简单处理(23. 5%).水平潜流人工湿地中段投加碱热处理香蒲,能明显提高湿地脱氮效果,TN平均去除率对比空白对照湿地提高30. 3%,同时系统出水COD浓度不会显著提高,还能有效提高系统对污水中磷的去除效果,除磷效果相比空白组提高33. 9%.更多还原

【Abstract】 Nitrogen removal in constructed wetlands( CWs) is highly affected by the supply of organic carbon. Thus,to enhance nitrogen removal in the horizontal subsurface flow of CWs,plant carbon sources were added during the downstream portion of the wetland. Moreover,the characteristics of static release and the denitrification potential of Typha were evaluated using three different pretreatment methods( i. e.,minced,acid-heated,and alkali-heated). The average concentrations of COD released and the nitrate removal rate with the alkali-heated,acid-heated,and minced Typha were 89. 57 mg·L-1 and 75. 2%,67. 27 mg·L-1 and 67. 2%,and 54. 45 mg·L-1 and 23. 5%,respectively. The results showed that different pretreatment methods resulted in the release of different amounts of acetic acid,and the alkali-heated Typha performed much better than the other pretreatments. Therefore,the alkali-heated Typha was selected and added to the middle of the horizontal subsurface flow CW,which improved the nitrogen-removal rate significantly; the average removal rate of TN and TP was higher than that of a control CW by 30. 3% and 33. 9%,respectively.However,the COD concentration of the CW with the alkali-heated Typha was not significantly increased.更多还原