Removal of soluble iron (II) and manganese (II) from water, although a number of treatments have been developed, but for some smaller water treatment plants or in certain emergency situations,
For example, when the concentration of iron and manganese in the water source increases sharply in the summer, the traditional physical and chemical removal methods are still relatively flexible and effective. This paper reports the use of chlorine dioxide pre-oxidation combined with manganese sand filtration to remove iron and manganese from drinking water. The removal efficiency of iron (II) and manganese (II) was compared using different filter materials (natural manganese sand, quartz sand and fiber bundle filter materials). Chlorine dioxide dosage, liquid flow rate, particle size of filter material, filtration The effect of the thickness of the bed on the removal efficiency was also tested. In addition, the optimum operating conditions for the removal of iron (II) and manganese (II) by chlorine dioxide pre-oxidation and manganese sand filtration were also analyzed.
The results show that natural manganese sand is more effective in removing iron (II) and manganese (II) than quartz sand and fiber bundle filter materials. As the pre-oxidant dose increases, the liquid flow rate decreases, the filter sand particle size decreases, the filter bed thickness increases, and the manganese removal efficiency increases. When the initial concentrations of manganese (II) and iron (II) in the feed water are 1.5 and 1.0 mg/L, the chlorine dioxide dose is 0.99 mg/L, the liquid flow rate is 282.6 mL/min, and the sand particle diameter is 0.6-1.2 mm. When the filter bed thickness is 60 cm, the process shows good removal of iron (II) and manganese (II), and the removal rates of iron (II) and manganese (II) are both over 95%.
