| 摘要: | 本研究為改善水平流潛流式人工濕地(Horizontal subsurface flow constructed wetland；SSF-H CW)因傳氧效率不佳所衍生的低汙染處理效率缺失，特利用前端曝氣及內迴流來增加系統污染物去除效能，相關系統設置地點位於嘉南藥理大學之生態池區域，藉由實驗組(SSF-H)與對照組(SSF-F)系統的水質淨化效能比較探討本研究所設計改良方式對SSF-H CW汙染處理效能特性之影響，其評估之水質指標包括生化需氧?(Biochemical oxygen demand；BOD)、氨氮(Ammonia-nitrogen；NH3-N)、硝酸氮、亞硝酸氮、總凱氏氮(Total Kjeldahl nitrogen；TKN)、總氮(Total nitrogen；TN)、總磷(Total phosphorous；TP)等，以下謹對本研究的重要成簡述之。根據本研究的研究成果可知SSF-H系統之第一試程時BOD的去除率達約83.2%，SSF-F系統BOD去除率只有52.8%，而在在第二試程中將SSF-H溶氧量調整至4mg/L，結果顯示BOD去除率達到89.1%，有此可知內迴流設計與曝氣系統可有效提升對BOD的去除效率。此外，本研究SSF-H系統在兩段試程中的NH3-N去除率皆高達到98%以上，而對照系統只有15.1-62.4%的去除效率，此亦顯示曝氣內迴流對硝化作用具有效正面影響，不僅如此，TKN的去除效率亦呈現類似的特性變化。至於SSF-F系統第一試程的TN去除率僅有約30%，而SSF-H系統於TN的去除效率則提高為77.8%，而在第二試程中仍有81.3%的TN去除率，由此可見曝氣內迴流可有效解決以曝氣方式提升SSF-H CW汙染去除效能時所造成的硝酸鹽氮累績問題，同時可有效提升TN之去除效能。然而在SSF-F系統與SSF-H系統各試程之TP去除率相比較中可發現內迴流曝氣的設計對TP去除率上無太大影響。由前述之討論可知內迴流曝氣對SSF-H CW之有機汙染物與含氮汙染物可有效提升其處理效能，但對TP去除率則無明顯影響。
To improve the low efficiencies of pollutant degradation induced by lacking of sufficient oxygen transportation, a modification using the artificial aeration and internal recirculation (AAIR) was installed in a horizontal subsurface flow (SSF-H) constructed wetland (CW). In the campus of Chia-Nan university of pharmacy and science, there were 2 systems established in this study which included an experimental system and a control one with identical dimension. The former (SSF-H-H) installed the modification of AAIR while the other (SSF-H-F) was regarded as a control system which only possessed a gravel bed and the aquatic plant (Hydrocotyle verticillata Thunb.). The water quality parameters; biochemical oxygen demand (BOD), ammonia-nitrogen (ammonia-nitrogen; NH3-N), nitrate-nitrogen, nitrite- nitrogen, total Kjeldahl nitrogen (TKN), total nitrogen (TN), and total Phosphorus (TP) were used to evaluate the removal efficiencies of SSF-H-H and SSF-H-F. According to the experimental results, the BOD removal rate of SSF-H during the first stage was about 83.2%, while the removal rate of SSF-F system was only 52.8%. In the second stage, the DO of SSF-H was adjusted to 4 mg/L and the result showed that the removal rate reached 89.1%. It showed that AAIR could effectively improve the removal efficiency of the BOD. In addition, NH3-N removal rates of SSF-H system in both stages were all higher than 98%, while the removal efficiency of the control system was only 15.1-62.4%. This also showed that AAIR had an effective positive effect on the nitrification process. Moreover, TKN removal efficiency also presented a similar characteristic tendency. As for the SSF-F system, the TN removal rate was only about 30% and the corresponding one of was 77.8%. It became 81.3% in the second stage. It implied that AAIR resolved the nitrate-nitrogen accumulation induced by applying the artificial aeration to improve the pollutant removal efficiency of SSF-H CW. At the same time, it could effectively improve the removal efficiency of TN. However, when comparing the TP removal in SSF-F system with that in SSF-H, AAIR had no obvious influence on TP removal rate. Based the above discussion, AAIR could significantly improve the removal efficiencies of organic and nitrogen contained pollutants but played no effective role in TP removal. |
