摘要
提出一种利用电化学除铁的水处理新技术 ,不需添加化学药剂且无二次污染 ,其作用机理是利用阳极 (不溶性 )反应产生的新生态氧和溶解氧将Fe2 +氧化成Fe3+,进而水解形成氢氧化铁胶体 ,再通过砂滤去除。阴极反应生成的OH- 引起pH值上升 ,提高了氧化速度 ;产生的微气泡促使高铁胶体集聚成较大的颗粒 ,改善了过滤条件。电流密度越高除铁能力越强 ,但电流效率下降。试验采用的电流密度为 4 .0mA/cm2 、通电率为 5 0C/L ,水流通过单程处理 ,含铁量由 4 .0mg/L降至 0 .3mg/L以下。采用循环处理方法可有效清除水箱黄锈水 ,其耗电量≤0 .0 2 (kW·h) /m3。
A new electrochemical technology of water treatment for iron removal was proposed, which did not need any chemical agent and had no secondary pollution. The performance mechanism was electrolysis. Fe 2+ was oxidized to Fe 3+ by nascent oxygen and dissolved oxygen produced by anodic reaction (with dimensionally stable anodes), the Fe 3+ was hydrolyzed to ferric hydroxide, and then the hydrolysate was filtrated off by sand-bed filter. As pH increased due to the increase of OH - formed by cathode reaction, the oxidation rate was increased. The ferric hydrocolloid particles were flocculated into much bigger flocs by small bubbles produced during electrolysis process, so that the condition of filtration was improved. The higher the electrical charge passed per litter of water the higher the ability of iron removal, but the lower the current efficiency. The total iron content was decreased from 4.0 mg/L to ≤0.3 mg/L, under the test conditions of current density 4.0 mA/cm 2, electrical charge per litter of water ≥50 C/L (H 2O), and single - pass operation, with quartz sand media adopted. Through circulating treatment, the rusty brown water in tank was cleaned efficiently, and the electric power consumption was ≤ 0.02 (kW·h)/m 3 (H 2O). The test result showed that the circulating treatment is applicable to water supply system of urban buildings.
出处
《中国给水排水》
CAS
CSCD
北大核心
2002年第6期10-13,共4页
China Water & Wastewater
基金
国家自然科学基金资助项目 (5 973815 0 )
