水资源管理与污染防治水污染防治之探讨.PPT

(1) Raw sewage drains by gravity into the first pool and flows through a long perforated PVC pipe into a bed of limestone gravel. (3) Wastewater flows through another perforated pipe into a second pool, where the same process is repeated. (2) Microbes in the limestone gravel break down the sewage into chemicals that can be absorbed by the plant roots, and the gravel absorbs phosphorus. (4) Treated water flowing from the second pool is nearly free of bacteria and plant nutrients. Treated water can be recycled for irrigation and flushing toilets. 45 centimeter layer of limestone gravel coated with decomposing bacteria First concrete pool Second concrete pool Sewage Wetland type plants Wetland type plants Treated water Figure 19-19 Page 506 （1）Raw sewage drains by gravity into the first pool and flows through a long perforated PVC pipe into a bed of limestone gravel. 由未經處理的污水藉由重力進入第一池，並流經長條穿孔PVC管到石灰岩礫石床。 (2) Microbes in the limestone gravel break down the sewage into chemicals that can be absorbed by the plant roots, and the gravel absorbs phosphorus. （2）在石灰岩礫石微生物將污水分解成化學物質，可以通過植物根系吸收，而礫石可以吸收磷。 (3) Wastewater flows through another perforated pipe into a second pool, where the same process is repeated. 廢水流經另一穿孔管進入第二個池，而同樣的過程重複進行。 (4) Treated water flowing from the second pool is nearly free of bacteria and plant nutrients. Treated water can be recycled for irrigation and flushing toilets. 從第二池流入處理後的水，是從近乎沒有細菌和植物營養素。處理後的水可循環用於灌溉和沖廁所。 45 centimeter layer of limestone gravel coated with decomposing bacteria 45厘米石灰岩礫石層塗有分解細菌 八、地下水之污染與防治 （一）地下水之自清作用力較地面水低（∵地下水之流速慢，污染物質不易稀釋、擴散，分解性細菌含量少） ˙地下水污染之主要來源：（P.494） 1.地下儲存槽滲漏含毒之有機化學物質 2.地下深井堆放含毒物質 ˙地下水污染防治之困難： 1.管制不嚴，不易察覺 2.設置偵測井昂貴又不一定有效。 露天煤礦逕流 取水井 廢棄潟湖 偶發溢出 Groundwater flow Confined aquifer Discharge Leakage from faulty casing 危險的廢棄物投入井 殺蟲劑和肥料 加油站 埋於地下之石油和鎔劑槽 Sewer 化糞池 除冰鹽路 不受壓淡水含水層 受壓淡水含水層Confined freshwater aquifer 取水