Iron Filters > Manganese Greensand


Manganese Greensand is formulated from glauconite greensand, which is capable of reducing iron, manganese and hydrogen sulfide from water through oxidation and filtration. Soluble iron and manganese are oxidized and precipitated by contact with higher oxides of manganese on the greensand granules. Hydrogen sulfide is reduced by oxidation to an insoluble sulfur precipitate. Precipitates are then filtered and removed by backwashing. When the oxidizing capacity power of the Manganese Greensand bed is exhausted, the bed has to be regenerated with a weak potassium permanganate (KMnO4) solution to restore the oxidizing capacity of the bed. 1.5 to 2 ounces of potassium permanganate, in solution, per cubic foot of Manganese Greensand is considered sufficient for normal regeneration. Vigorous backwashing and regeneration of the bed is required when it is placed in service and before its oxidation capacity is totally exhausted. Operating the bed after oxidation capacity is exhausted will reduce its service life and may cause staining.


Iron reduction over wide pH range
Effective reduction of hydrogen sulfide in addition to iron and/or manganese
No harmful effects from a chlorine feed
Low attrition for long bed life


Color: Black
Bulk Density: 85 lbs./cu. ft.
Specific Gravity: 2.4-2.9
Effective Size: 0.30-0.35 mm
Uniform Coefficient: 1.6
Mesh Size: 16-60
Attrition Loss Per Year: 2%
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Water pH range: 6.2-8.5
Maximum water temperature: 80°F/26.7°C
Bed depth: 30 in.
Freeboard: 50% of bed depth (min.)
Regeneration: 1.5-2 oz of KMnO4 by weight per cu. ft.
Service flow rate: 3-5 gpm/sq. ft., 8-10 gpm/sq. ft. intermittent flow possible
Backwash flow rate: 10-12 gpm/sq. ft.
Backwash bed expansion: 40% of bed depth (min.)
Maximum practical limit of iron (Fe++) or manganese (Mn++) in raw water: 15 ppm
Maximum practical limit of hydrogen sulfide (H 2 S): 5 ppm
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Iron alone:
600 grains (10,000 gal. of water containing 1 ppm iron/cu. ft.)
Iron and manganese:
400 grains (7,000 gal. of water containing 0.5 ppm iron and 0.5 ppm manganese/cu. ft.)
Hydrogen sulfide:
175 grains (3,000 gal. of water containing 1 ppm hydrogen sulfide/ cu. ft.)
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Service Flow Pressure Drop and Backwash Bed Expansion charts to be added later. Check back for updates.