UVオゾン酸化とイオン交換樹脂法による1，4-ジォキサン含有排水の処理とリサイクル

摘要

Wastewater containing 1,4-dioxane and detergent from metal washing processes was treated using UV ozone oxidation and ion exchange resin. The chemically stable 1,4-dioxane was decomposed easily and quickly by UV ozone oxidation. The oxidized water was deionized using ion exchange resin by applying a mixed bed resin system. The electric conductivity of the effluent from the ion exchange resin column was less than1.2 μS cm . COD (Chemical Oxygen Demand) and TOC (Total Organic Carbon), which indicate organic matter contents, were1.0 mg dm (-3) and 0.15 mg dm(-3), respectively. This purified water is reusable as rinsing water during surface finishing. Based on these experiments, we devised a practical recycling system by which contaminated wastewater can be decontaminated and reused as purified water on an industrial scale at a surface finishing factory. A salient benefit of this combined process (UV ozone oxidation and ion exchange resin method) is that it uses no chemicals and that it entails no production of salts that must be removed before using the treated water. These results suggest that this process causes no secondary pollution, and that it has a high probability of practical application as recycling water during surface finishing.%自動車，電気，機械部品等の洗诤剂として従来からハロゲン系有機溶剤が多く使用されている。ハロゲン系有機溶剤のうちフッ素系溶剤は，ォゾン層破壊物質として段階的削減の後，2020年に生産全廃の予定である。塩素系溶剤は，人体への毒性，土壌汚染.地下水汚染，大気汚染等の環境問題により规制強化の傾向にある。