摘要
太陽能板電池製造過程包括，矽材料、長晶、拉晶、切晶、蝕刻、清洗、擴散、鍍膜、印刷等製程，製程中會使用各種酸鹼化學品，進行蝕刻或清洗，有氫氟酸、硝酸、硫酸、鹽酸及KOH等。其製程產出之清洗廢水，分為高濃度酸性廢液、高濃度鹼性廢液、低濃度酸性清洗廢水及低濃度鹼性清洗廢水等，其主要污染源為矽酸鹽及氟化物等。本研究目的為，將太陽能板電池製程中，低濃度酸性清洗廢水及低濃度鹼性清洗廢水，獨立分開收集後，個別經pH調整及初級過濾後，再將出流水導入RO單元，藉由模廠之實際運作，來評估RO單元之處理效能，及其未來應用在清洗廢水回收之可行性。RO模組經過四個月連續操作測試，針對低濃度鹼性清洗廢水，其二氧化矽去除率可達96.9% ~ 98.6%，而氟化物去除率也高達97.6% ~ 99.2%，整體水回收率達80％，水質皆符合回收水標準，可當作自來水的替代用水。在低濃度酸性清洗廢水測試中，由於其二氧化矽及氟化物濃度相對偏高，RO連續運轉不到72小時，即阻塞且無法清洗。所以利用RO進行廢水回收，應用在低濃度鹼性清洗廢水回收是可行的，但此法無法應用在低濃度酸性清洗廢水回收上。
關鍵字：化學需氧量、生化需氧量、太陽能廢水、逆滲透、化學機械研磨。
ABSTRACT
Solar cell manufacturing processes involves of silicon,Multi crystallization Silicon ingot, Crystal growth, wire-saw, etching, cleaning, sputter, plate, print. Used in all kinds of acid and alkali chemicals in processes of etching or cleaning, ex. hydrofluoric acid, nitric acid, sulfuric acid, hydrochloric acid and KOH. Cleaning waste water of manufacturing processes divided into high concentration of acidic waste liquid, high concentration of alkaline liquid, low concentration acid cleaning wastewater and low concentration of alkali washing wastewater. The main pollution sources such as fluoride and silicate. Purposes of this study, Solar cell manufacturing processes, separate collection of low concentration acid cleaning wastewater and low concentration alkaline cleaning wastewater, after pH adjustment and the primary filter, individual, then import water RO units. Through actual operation of the pilot scale to evaluate the treatment efficiency of RO units, and its future application of recycling feasibility in cleaning wastewater. After four months of continuous operation test the RO module, for alkaline cleaning wastewater with low concentration, the silica removal rate up to 96.9%~98.6%, and fluoride removal rates as high as 97.6%~99.2%, overall water recovery rate of 80%. Water quality of secondary water are in compliance with the standard. In the test of low concentration acid cleaning wastewater, because of its relatively high concentration of silica dioxide and fluorides, RO is blocked and cannot be cleaned when continuous operation less than 72 hours. Use of RO in wastewater recycling, it is feasible on the low concentrations of alkali cleaning wastewater recycling, but not applied on the low concentration acid cleaning wastewater.
Keywords: P Chemical Oxygen Demand; Biological Oxygen Demand; Solar Cell Wastewater; Reverse Osmosis; Chemical Mechanical Polishing
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