采用柱状模拟器依次设计了潮汐上行和潮汐下行流人工湿地,以连续上行和连续下行流人工湿地作为对照,探讨了潮汐流人工湿地在秋季对模拟生活污水的净化能力和处理稳定性。研究表明,潮汐上行流、潮汐下行流、连续上行流、连续下行流对COD平均去除率分别为65.05%±9.07%、63.64%±8.24%、26.90%±8.49%、40.84%±6.18%。对TP平均去除率依次为45.57%±10.86%、40.16%±14.15%、23.23%±11.09%、33.28%±7.99%。潮汐上行流湿地对TN、NH+4-N去除率分别为40.63%±7.69%、23.26%±7.58%,潮汐下行流为35.98%±11.95%、22.68%±9.18%,高于连续上行流的8.20%±5.62%、11.72%±7.32%和连续下行流的13.06%±6.12%、23.38%±9.16%。4种湿地并未出现硝态氮累积现象,潮汐上行流和潮汐下行流人工湿地出水亚硝态氮总体变化趋势较为一致。连续上行流和连续下行流人工湿地,出水亚硝态氮和进水较为接近基本在0.02 mg·L-1左右。在湿地出水氮成分中,有机氮、NH+4-N、NO-3-N、NO-2-N占TN的平均比例依次为16.72%±3.50%、72.74%±6.49%、10.27%±3.84%、0.28%±0.20%。整体而言,在秋季潮汐流湿地对污染物也表现了较高的处理效果,且净化能力优于连续流湿地。
In this study,tidal upflow and downflow constructed wetlands were designed using a column simulator to treat domestic sewage and investigated for their stability in autumn,whereas continuous upflow and downflow constructed wetlands were used as control groups. The results showed that the average COD removal efficiencies of the tidal upflow,tidal downflow,continuous upflow,and continuous downflow constructed wetlands were 65. 05% ± 9. 07%,63. 64% ± 8. 24%,26. 90% ± 8. 49%,and 40. 84% ± 6. 18%,respectively,and the average removal efficiencies of TP were 45. 57% ± 10. 86%,40. 16% ± 14. 15%,23. 23% ± 11. 09%,and33. 28% ± 7. 99%,respectively. Furthermore,the average removal efficiencies of TN and NH+4-N in the tidal upflow constructed wetland were 40. 63% ± 7. 69% and 23. 26% ± 7. 58%,respectively,and the corresponding removal efficiencies in the tidal downflow constructed wetland were 35. 98% ± 11. 95% and 22. 68% ± 9. 18%.The TN and NH+4-N removal efficiency of tidal flow constructed wetlands were higher than that of continuous up flow and down flow constructed wetlands which were 8. 20% ± 5. 62%,11. 72% ± 7. 32% and 13. 06% ±6. 12%,23. 38% ± 9. 16%. During the sampling period,nitrate did not accumulate in any of the four types ofwetlands. The concentration of nitrite in the tidal upflow and downflow constructed wetlands varied identically. In addition,the concentrations of nitrite in the continuous upflow and downflow constructed wetlands were closer to those at the inlets( approximately 0. 02 mg·L-1). The average proportions of organic nitrogen,NH+4-N,NO3-N,and NO-2-N in the TN were 16. 72% ± 3. 50%,72. 74% ± 6. 49%,10. 27% ± 3. 84%,and 0. 28% ± 0. 20% at the outlets,respectively. Overall,the tidal flow wetlands had a strong ability to purify domestic sewage during autumn and performed better than the continuous flow wetlands did.