高硬度含铁含锰地下水的处理

Treatment of high-hardness groundwater containing iron and manganese

黑龙江双城市净水厂原水取用地下水,其含有铁、锰和高硬度,采用石灰软化法、曝气和常规水处理工艺,处理后水中的铁、锰和硬度均达到《生活饮用水卫生标准》(GB 5749—2006)。但由于采用石灰软化去除硬度,出水中残存的硬度多以CaCO3和Mg(OH)2沉淀物形式存在,致煮沸水中表面有白色沉淀物薄膜,因此采取在滤后水中加入少量盐酸的方法,使煮沸水中不再出现白色沉淀物薄膜。去除硬度的生产废水中含有高浓度的CaCO3和Mg(OH)2沉淀物,直接排放会堵塞下水道和污染接纳水体,故进行了生产废水处理以利于环境保护和污泥回收利用。

Shuangcheng City Water Treatment Plant uses groundwater as raw water, which contains iron, manganese, and high-hardness. The processes of lime softening, aeration and conventional water treating process were employed and the iron concentration, manganese concentration and hardness in treated water met the requirements of Standards for drinking water quality （GB5749-2006）. However, the lime softening process was used to remove the hardness, so the residual hardness was mainly composed with CaCO3 and Mg（OH）2 sediments, which would cause white sediment membrane on the surface of boiled water. After the hydrochloric acid was dosed into the water after filtration, the white sediment membrane disappeared. The high concentration CaCO3 and Mg（OH）2 sediment should be removed from the production wastewater. If it were discharged directly, it might cause the pipe blocking and polluted the downstream receiving water. As a result, treating the production wastewater would be in favor of the environment protection and sludge reuse.