製紙廃水処理における高分子凝集剤の最適添加量

摘要

製紙工場廃水は浮遊性固形物と溶存性物質の混合体である汚染物質で，その固液分離過程は廃水処理工程の中で重要な一環である.固液分離過程では相当量のスラッジが発生し，中には重金属が含まれている場合もあり，含水率が高いという問題点がある.一般的に，スラッジ処理費は廃水処理全体費用の約45%を占めている.%In this study, the effect of polymer flocculants (anionic polyacrylamide and cationic polyacrylamide)on sludge dewatering and floc strength was evaluated. The dual polymer system was preferred in terms of sludge dewatering and floc strength. The optimum dosage of the dual polymer system was 100-150ppm. Also, the combined use of two polymers was superior to the single polymer system in terms of COD removal. Compared with the single polymer system, the use of the dual polymer system resulted in further increase in COD removal by 15-20%. In the case of single polymer system, cationic polyacrylamide was better than anionic polyacrylamide. Charge density approached positive with the increased addition of the cationic polymer.