Internal Treatments of OCC Mill White Water

工業用紙造紙白水中間處理之研究

王益真(I-Chen Wang) ； 王國財(Kuo-Tsai Wang)

《台灣林業科學》 16卷4期 (2001/12) Pp. 217-226

https://doi.org/10.7075/TJFS.200112.0217

摘要

國內工業紙製造大部份依賴回收紙板，儘管其單位產量用水已降至頗低水準，但仍將有環保壓力促使用水量更減。本研究探討數種短水力停留期的處理方法，包括超過濾、短期活性污泥、加壓浮除及沙濾等應用於某廠白水水樣以期能改善循環白水水質，延長循環次數以達減少用水之目的。處理效果的評估係處理後分析水質以及使用該白水分散探自該廠之芯紙漿料抄造手抄紙並比較紙張性質。超過濾後水中懸浮固體量最低，但仍留存低分子量溶解固體；超過濾白水使手抄紙質地鬆散，紙力低下，可能係因有助纖維鍵結的膠體分子遭去除，僅留存低分子量干擾性鹽類與有機物所致。超過濾後施以短期活性污泥處理可去除部份干擾物質，得使手抄紙紙力回升。加壓浮除法及添加凝集助劑或系列浮除處理可相當有效去除白水中的懸浮固體，輔以沙濾更可有效改善水質及手抄紙性質。惟白水系統如欲密閉化，則可能需用到高價的逆滲透、離子交換及活性碳等處理，對高污染負荷的工業紙生產尚難適用。

關鍵字

造紙白水 ； 中間處理 ； 超過濾 ； 加壓浮除 ； 沙濾 ； 手抄紙性質

並列摘要

The domestic paper industry producing packaging board from old corrugated containerboard (OCC) is based on recycled fiber resources. Several treatment methods including ultrafiltration (UF), short hydraulic retention time (HRT) activated sludge (AS) treatment, dissolved air flotation (DAF), and sand filtration (SF) were applied to white water samples collected from an OCC mill. Treatment effects were then evaluated by analyzing water quality and using treated water to disperse semi-dried pulp collected from the corrugating medium line of the mill to make handsheets for property comparisons. Ultrafiltration gave water of low suspended solids (SS) but was ineffective in removing low-molecular-weight dissolved substances in water. UF-treated water led to bulkier, loosely bonded handsheets with lower strength properties. This is believed to be due to the removal of some fiber bond-enhancing macromolecules from the water, while retaining dissolved organic substances and salts that interfered with fiber bonding. Short HRT activated sludge treatment following UF enabled removal of some of the interfering substances and resulted in marked improvement in handsheet properties. DAF and variants using chemical coagulation and serial treatments removed SS fairly well, but were generally ineffective against dissolved substances. Sand filtration following DAF produced better water quality and handsheet properties. Closing the white water loop may entail expensive treatments that are yet impractical for the packaging grades involved.

並列關鍵字

white water ； internal treatments ； dissolved air flotation ； ultrafiltration ； sand filtration ； handsheet properties