Birm is an efficient and economical method of removing iron and manganese compounds from raw water supplies. It may be used in either gravity fed or pressurized water treatment systems. It acts as insoluble catalyst to enhance the reaction between dissolved oxygen (D.O.) and the iron compounds.In ground water dissolved iron is normally in the ferrous bicarbonate state due to the excess of free carbon dioxide and is not filterable. Birm acts as a catalyst between the oxygen and soluble iron compounds and enhances the oxidation reaction of Fe++ to Fe+++ and produces ferric hydroxide which precipitates and is easily filtered.
Birm is easily cleaned by backwashing to remove the ferric hydroxide. It is not consumed in the iron removal process and therefore provides a positive economic advantage over many other iron removal medias.
Other advantages of birm include long material life with relatively low attrition loss, a wide temperature performance range and extremely high removal efficiency. Under the proper water conditions, no chemicals are required for maintenance. Regeneration is not required.
Birm is also used to achieve manganese reduction. When used to reduce manganese, the water to be treated should have a pH between 8.0-9.0 for best results. If both manganese and iron are to be removed, the treated water should have a pH below 8.5.
- Under the proper conditions, no chemicals to purchase for maintenance. Regeneration not required.
- Iron removal efficiency in extremely high.
- Negligible labor cost: only periodic backwashing required.
- Durable material with a long life and wide temperature range.
- Color: black
- Bulk Density: 44 - 50 lbs./cu. ft.
- Specific Gravity: 2.0
- Effective Size: 0.59 mm
- Uniformity Coefficienty: 1.96
- Mesh Size: 9 x 35
- Water pH range: 6.8 - 9.0
- Bed depth: 30 – 36 in.
- Freeboard: 50% of bed dept (min.)
- Service flow rate: 3.5 – 5 gpm/sq. ft.
- Backwash flow rate: 10 – 12 gpm/sq. ft.
- Backwash expansion rate: 20 – 40% of bed