Filter material for removal of manganese and iron from drinking water contains two types of graded mineral particles

摘要

A drinking water filter material consists of mineral ore that represents 1-50% of the filter by weight and incorporating at least 80 wt.% manganese dioxide in the ore. The filter further contains a second particulate material representing 50 to 99 wt%. The second material consists of chalk-coated manganese dioxide. The first and second type of particles represent at least 90 wt.% of the filter material. A suitable mixture ratio is 10-15% of the first particle and 85-90 wt.% of the second particle. The chalk coating is derived from limestone, dolomite, marl-stone and/or calcium silicate, and contains a binding agent e.g. cement representing 5-15 wt.% of the second particle. The particle grain size is 0.7 to 1.5 mm and has a bulk weight of about 1.5 tons/m3.