1、生活污水之濕地處理及再利用研究Application of Constructed Wetland in Domestic Wastewater Effluent: Treatment & Reuse研究生：張立弘 Chang Li-Hung指導教授：郭文健 Kuo Wen-Chien【摘要】近一、二十年濕地逐漸被應用在水污染防治以及水資源保育，至目前為止已有超過一千個濕地系統被實際應用，其中更以人工濕地系統(Constructed wetland system)為多數，其應用及研究大多是將人工濕地作為二級處理程序或高級處理程序，處理都市污水、工業廢水、垃圾滲出水或礦場滲出水。本研究以人工濕地
2、處理二級生活污水場之放流水，以不同的濾材介質與操控條件，求得最佳之濕地設計與操控參數，並且研究水資源回收再利用與廢棄爐石再利用之可行性。本研究之人工濕地為一模場試驗，處理二級污水處理場的放流水。人工濕地各槽的設計規格是以長10m、寬 3m、高 1.2m，前後高度差為 0.2m，為 1：50 的坡度，以重力流的方式向放流口流動。研究中所使用的濾材介質包括了中鋼爐石及卵石，實驗分為四個不同階段，以不同之水力停留時間作為操控條件，分別為 1/6 天、5 天、3 天及 1 天，期間每週採樣一次，進行分析。由實驗結果可得知，人工濕地對於 SS 的去除率(爐石槽 3294%；卵石槽 290%)、BOD(爐
3、石槽 16100%；卵石槽 13100%)及 COD(爐石槽 480%；卵石槽 972%)有良好的去除功能，氮( 爐石槽 532%；卵石槽 349%)、磷(爐石槽 961%；卵石槽 348%)的去除效果卻不是太好，可能原因為植物種植及收割不規律，導致植物體腐爛之後，將吸收的氮磷又釋放至濕地系統內，使得氮磷的移除並沒有很完全，植物適時的收割對於氮磷的去除有相當大的影響。爐石濾床在 SS 及 BOD5 的去除效果，皆明顯優於卵石濾床，推斷是爐石表面有非常多不規則的孔隙，可以提供比卵石更多的表面積讓微生物附著生長，也能讓懸浮固體物有更佳的留滯效果。因此，廢棄爐石在濕地濾材的利用方面是可以推行應用的。
4、就經濟效益方面而言，當水污費開徵之後，水質、水量皆是水污費計算之重要指標，如果能以人工濕地作為第三級處理，減少污染排放量，以長遠的眼光看來，人工濕地能夠扮演一節省污水處理成本、降低水污費之重要角色。本研究中以一階動力模式推導出一階反應速率常數 k 值，並以實驗所得之 k 值設計出符合水資源再利用之人工濕地規格，可供為未來本土人工濕地規劃設計之用。關鍵字：生活污水 人工濕地 地下流式 【Abstract 】Constructed wetlands are artificial wetlands built to provide wastewater treatment. They have be
5、en used to treat variety of wastewater including urban runoff, municipal, industrial, agricultural wastewater, and acid mine drainage. In this study, constructed wetland was built next to a secondary wastewater treatment plant of National Pingtung University of Science and Technology. With different
6、 media and flow rates applied, optimized design and operating parameters of constructed wetland were investigated.In this study, constructed wetland was a pilot scale. The effluent of the secondary wastewater treatment plant discharged to the constructed wetland. Each unit was built with the same di
7、mension (LWH) 10m3m1.2m, with two different media: air-cooled blast furnace slag and rocks. The Hydraulic Retention Times (HRTs) tested were 1/6 day, 1 day, 3 days, and 5 days.In the overall performance in slag filter bed (A) and rock filter bed (B), removal efficiency of the Suspended Solids (SS) (
8、A:3294%；B: 290%)、BOD(A:16100%；B:13100%) and COD(A:480%；B:972%) were good, but removal efficiency of Nitrogen (A:532%；B:349%)、Phosphrous (A:961%) were not as good as SS、 BOD and COD. The reason could be attributed to irregu harvest of the plants grow in the wetland. Slag filter bed was better than ro
9、ck filter bed in the removal efficiency of SS and BOD. Because slag had more small holes on surface. It can provide more specific surface for microorganism attachment and suspended solids retention. Slag can serve as a good medium in constructed wetlands. The experimental data were analyzed by fitting them to the first order kinetic model to obtain kinetic constant, k, “k values” can be used in design of local constructed wetland in wastewater reclamation.Keywords: Domestic Wastewater , Constructed Wetland , Subsurface Flow
