生态沟渠对水中氮磷去除效果的模拟研究

Simulation Study on the Absorption of Nitrogen and Phosphorus in Water by Ditch Plants

【目的】研究不同进水流量下不同植物立体组合的生态沟渠对氮磷的去除效果,为田间生态沟渠的构建提供参考。【方法】利用室内搭建的生态沟渠模拟装置,开展不同植物组合C1(再力花Thalia dealbata-大薸Pistia stratiotes-九冠草Echinodorus major)、C2(再力花T.dealbata-凤眼莲Eichhornia crassipes-黑藻Hydrilla verticillata)和不同进水流量处理对水中氮磷的去除效果研究。【结果】不同植物组合和不同进水流量处理对水中氮磷去除效果不一。低进水流量(60 L/h)有利于植物生长且对水中氮磷吸收效果较好,此流量下,运行26 d后,C1与C2的总氮去除率分别达到36.74%和34.91%,氨氮去除率均达97%以上,总磷去除率均达95%以上。总磷和铵态氮质量浓度分别达到国家地表水环境质量标准Ⅱ、Ⅰ类水质标准。【结论】不同进水流量C2生物量增长均高于C1,但C1对氮磷的吸收量高于C2,去除效果较好。

【Objective】The effect of ecological ditch of different three-dimensional plant combinations on nitrogen and phosphorus removal under different influent flow was studied to provide reference for the construction of the field ecological ditch.【Method】The removal efficiency of nitrogen and phosphorus in water by different plant combinations-C1(Thalia dealbata-Pistia stratiotes-Echinodorus major)and C2(T.dealbata-Eichhornia crassipes-Hydrilla verticillata)and different influent flow treatments was studied by using an indoor ecological ditch simulation device.【Result】The removal efficiency of nitrogen and phosphorus in water by different plant combinations and different influent flow treatments was different.The results showed that the low influent flow rate(60 L/h)was beneficial to plant growth and had a good effect on nitrogen and phosphorus absorption in water.At this flow rate,the total nitrogen removal rates of C1 and C2 were 36.74%and 34.91%,the ammonia nitrogen removal rate was over 97%,and the total phosphorus removal rate was over 95%after 26 days of test operation.The concentrations of total phosphorus and ammonia nitrogen reached the ClassⅡandⅠwater quality standards of national surface water environmental quality standards,respectively.【Conclusion】Under different influent flows,the biomass growth of C2 was higher than that of C1,but the absorption of nitrogen and phosphorus by C1 was higher than that of C2 and the removal effect was better.