某印刷電路板廠所使用以陶粒為濾材的廢水生物處理系統,因為其陶粒本身物理特定的關係導致生物處理槽遭破壞,產生COD 去除效率不佳,甚至進流堵塞導致生物槽失效的問題,因此思考廠內是否有適合的廢棄物來取代陶粒的濾材,來解決生物槽遭破壞問題以及滿足廠內廢棄物再利用的環保績效。經過評估後發現廠內廢棄拉西環符合重量輕及適合當作微生物載體的特性,因此研究其取代既有陶粒濾材的可行性。本研究首先測試將廢棄拉西環清洗乾淨的反洗次數,及單位重量廢棄拉西環需要多少重量將其壓入水中,接下來架設及測試廢棄拉西環實驗模組,最後實驗比較廢棄拉西環模組與既有陶粒濾材生物系統的各項出流水水質的表現,以及增加廢棄拉西環模組進流量的出流水水質表現,來分析廢棄拉西環取代陶粒濾材的可行性。實驗結果顯示,利用既有系統反洗參數清洗一次廢棄拉西環即可將廢棄拉西環清洗乾淨而不影響出流水水質。每公克的廢棄拉西環需要0.1689 公克的重量將其完全沉入水中,日後可依照此參數作為實廠設計固定架的依據。在相同HRT之下,廢棄拉西環濾材有較高的COD 去除率,比陶粒濾材高24%,在Cu、Ni及SS 方面也有較高的去除率表現。將HRT 由3.0 hr 調整至1.0 hr 的實驗發現,廢棄拉西環濾材有較高的COD 體積負荷,高達1.65 kg*COD/m3*day,且在HRT=1 hr 的條件下,Cu、Ni 及SS 的去除率表現都比既有系統在HRT=3 hr 高,綜合上述的實驗結果,判斷廢棄拉西環導入廢水生物處理系統的可行性高。;A printed circuit board factory using ceramsites as its filtering material in the biological treatment system is faced with problems of damaged tanks due to the physical property of the material that has reduced its COD removal rate. Sometimes the tanks were even malfunctioned due to inflow jams. This study aims to find another adequate waste material that can substitute ceramsites as filter to reduce the biological treatment tank damage rate and reuse waste in the factory to enhance its environmental performance. After analysis, we have found raschig ring to be an appropriate substitute in its lighter weight and ability to serve as microbial carrier. This study first tested the backwash rate of raschig ring and the amount of water required to sink a unit weight of raschig ring. Second, we set up an experimental module and ran several tests according to the first outcome. Third, we compared the outflow water quality after filtered by the raschig ring and the existing ceramsites;meanwhile increasing the inflow amount in the raschig ring module to assess the possibility of replacing ceramsites with it. The result shows that it requires only one wash to clean a raschig ring without influencing the outflow water quality. Every gram of raschig ring can be sink completely in 0.1689 g of water, which can serve as the reference for future fixure design in factories. Under the same HRT, waste raschig ring has a 24% higher COD removal rate than ceramsites and performed better in the removal of Cu, Ni, and SS. While adjusting HRT from 3.0 hr to 1.0 hr, raschig ring has a higher COD volume loading, which is 1.65 kg*COD per m3*day. Under the condition of HRT=1 hr,raschig ring has a higher Cu, Ni, and SS removal rate compared to that of HRT=3 hr,based on the above experimental results,it is highly feasible to judge the raschig ring biological wastewater treatment system.