传统饮用水净化工艺对锰的去除特性

Manganese removal characteristics in traditional drinking water purification process

锰广泛存在于天然水体中,含量过高对人体健康存在诸多不良影响。将膜分离与电感耦合等离子体质谱分析技术相结合,深入探讨了传统饮用水净化工艺对溶解态和悬浮态锰的去除规律。结果表明,随着水深的增加,水源水体中的总锰呈上升趋势,溶解态锰则无明显变化。在各处理单元中,混凝-沉淀过程对颗粒态锰的脱稳沉淀和部分溶解态锰的吸附去除起着主要作用,砂滤对溶解态锰的氧化去除可以忽略;当原水中的总锰含量在0.28 mg·L-1时,处理出水中的锰含量在0.21 mg·L-1,平均去除率仅为25%。进行高锰酸盐预氧化,可有效提升总锰在后续各净化单元中的去除效率,处理出水可满足居民饮用水水质标准。

Elemental manganese is widespread in natural waters. Manganese is important for human health, but excessive exposure or intake may lead to manganism. In this work, membrane separation and induc- tively coupled plasma mass spectrometry were applied to explore the removal characteristics of dissolved and sus- pended manganese in a traditional drinking water purification process. The results show that the concentration of total manganese in raw waters increased with depth; however, the dissolved manganese showed no obvious change with depth. Coagulation-sedimentation processes play a major role in precipitation of particulate manga- nese, and adsorption and removal of partially dissolved manganese. The oxidation intercept effect of dissolved manganese on sand filters can be ignored. When the total manganese concentration in raw water was 0.25 mg · L-1 , the effluent concentration was 0.16 mg · L-1 and the average removal rate was 24.36%. Oxidation of po- tassium permanganate can effectively improve the removal rate of total manganese in the subsequent purification units. The effluent so treated can achieve the drinking water quality standards.