| 摘要: | 本研究自2011年7月至2012年6月，以一年時間連續紀錄及監測臺南市灣裡人工濕地系統的處理水量、水質，探討灣裡人工濕地系統的處理效益，作為未來灣裡人工濕地進行效益改善之建議，以及未來同類型人工濕地處理效益改善之參考。灣裡人工濕地系統位於台南市南區灣裡市場附近，總面積約5公頃，水域面積為1.3公頃，設計處理污水量為600 CMD，本研究進行期間實際處理污水量為80~300 CMD，水力負荷為0.0075~0.0319 m/day，採樣與水質分析頻率為每個月1次，以提供後序進行處理效益評估之依據。
實驗結果顯示，人工濕地進流水的pH值為7.3±0.2，出流水pH值為7.9±0.4，進流水溶氧濃度為1.0±0.8 mg/L，出流水溶氧值為5.5±2.0 mg/L；進流水懸浮固體物濃度為29.8±19.2 mg/L，出流水濃度為8.9±6.0 mg/L，去除效率為65.5±22.5 %，去除速率為2.41±1.64 kg/day，單位面積去除速率為0.23±0.16 g/m2/day；進流水生化需氧量濃度為21.9±5.5 mg/L，出流水濃度為6.1±3.6 mg/L，去除效率為70.6±16.6 %，去除速率為2.20±1.26 kg/day，單位面積去除速率為0.21±0.12 g/m2/day；進流水總氮濃度為14.5±7.0 mg N/L，出流水濃度為2.6±3.2 mg N/L，去除效率為82.5±13.5 %，去除速率為2.00±1.81 kg/day，單位面積去除速率為0.19±0.17 g/m2/day；進流水總磷濃度為2.427±0.737 mg P/L，出流水濃度為1.060±0.838 mg P/L，去除效率為53.5±26.0 %，去除速率為0.26±0.28 kg/day，單位面積去除速率為0.02±0.03 g/m2/day；大腸桿菌群進流水數量為3.5×106±2.6×106 CFU/100 mL，出流水數量為1.2×103±1.8×103 CFU/100 mL，去除效率為99.9 %。
從不同污染物在灣裡人工濕地的濃度變化，可發現不同污染物在不同處理單元中，污染物的削減受處理單元的結構特性而影響，本研究進一步將所獲得之數據與其他環保署所設置的人工濕地文獻值進行比對，結果發現本研究場址相對於文獻值處理水量偏低，具提升空間，另外由懸浮固體物、生化需氧量、氨氮、總磷四種污染物質的處理效益與其他人工濕地文獻值進行比對，檢討灣裡場址目前水力負荷與污染物去除效益，可獲得以下結果，懸浮固體物的水力負荷範圍可符合放流水規範，只考慮生化需氧量處理效益的場址水力負荷為0.05 m/day，只考慮氨氮處理效益的場址水力負荷為0.04~0.1 m/day，只考慮總磷處理效益的場址水力負荷為0.04~0.1 m/day，因此建議處理水量可調整為200 CMD ~ 300 CMD之間。
This study recorded and monitored data that consisted of water quantity & quality and how to reduce the level of pollution in the water from Wanli constructed wetland system(Wanli CW) in Tainan City between July 2011 year to June 2012 year.
This will be beneficial toward improving the constructed wetland in the future as well as acting as reference on similar site. Wanli CW system is located next to Wanli market in Tainan City, with a total area of 5 hectares constructed wetland system and water area of 1.3 hectares. The design of sewage treatment capacity is 600 CMD.
In this study, the actual sewage treatment capacity was 80 to 300 CMD with the hydraulic loading rate of 0.0075 to 0.0319 m/day. Water quality sampling from Wanli CW frequency was taken once a month and analysis results can be used as constructed wetland assessment to deal with the basis of efficiency..
This experimental result showed that Wanli CW had an average influent pH of 7.3� 0.2 while the average effluent pH was 7.9 � 0.4. The average influent DO concentration was 1.0� 0.8 mg/L while the average DO concentration of the effluent was 5.5�2.0 mg/L. The average influent SS concentration was 29.8�19.2 mg/L while the average SS concentration of the effluent was 8.9�6.0 mg/L, the SS removal efficiency was 65.5 � 22.5 %, average SS removal rate was 2.41 � 1.64 kg / day and the average area removal rate was 0.23 � 0.16 g/m2/day. The average influent BOD concentration was 21.9�5.5 mg/L. Our data showed that the average effluent BOD concentration was 6.1�3.6 mg/L and the BOD removal efficiency was 70.6�16.6 %, the average BOD removal rate was 2.20�1.26 kg /day while the average area removal rate was 0.21�0.12 g/m2/day. The average influent TN concentration was 14.5�7.0 mg N/L while the average effluent TN concentrationt was 2.6�3.2 mg N/L. We found the TN removal efficiency was 82.5�13.5 % with the TN average removal rate being 2.00�1.81 kg / day and the average area removal rate to be 0.19�0.17 g/m2/day. The average influent TP concentration was 2.427�0.737 mg P/L while the average effluent TP concentration was 1.060�0.838 mg P/L, the TP removal efficiency was 53.5�26.0 %, TP average removal rate was 0.26�0.28 kg / day and the average area removal rate was 0.02�0.03 g/m2/day. The influent average number of total coliformss were 3.5 � 106 � 2.6 � 106 CFU/100 mL, the effluent average number of total coliforms were 1.2 � 103 � 1.8 � 103 CFU/100 mL with the removal efficiency being 99.9%.
The study also found that by altering the concentration change of sewage contaminants in CWs will result in structure difference of the CW processing unit, thus affecting the removal efficiency of sewage contaminants.
We found different structure of the CW processing unit will affect the removal efficiency of sewage contaminants by changing the concentration change of sewage contaminants in CWs. Data obtained in this study compared with literature data from CW set by Taiwan EPA showed that sewage treatment capacity in this study CW site were lower than the other CW. In addition, sewage treatment efficiency of SS, BOD, TN, TP in this study CW site compared with literature data from other CW, and review hydraulic load rate and contaminants removal efficiency of Wanli CW gave the following results: the current treatment efficiency and hydraulic load can be resorted to water suspended solids concentrations to meet effluent standards. If only consider the BOD treatment efficiency can be fit with the literature data, the hydraulic loading rate of Wanli CW can operate for 0.05 m/day. If the NH3-N treatment efficiency can be fit with the literature data, the hydraulic loading rate of Wanli CW can operate for 0.04~0.1 m/day. By fitting the literature data with the TP treatment efficiency, the hydraulic loading rate of Wanli CW can operate for 0.04~0.1 m/day. Therefore, this study suggests that sewage water flow rate of Wanli CW can be adjusted to 200 ~ 300 CMD. |
