Birm

Birm (for Iron Removal)

Birm is an efficient and economical method of removing dissolved iron and manganese compounds from raw water supplies. It may be used in either gravity fed or pres sur ized water treatment systems. Birm acts as an insoluble catalyst to enhance the reaction between dissolved ox y gen (D.O.) and the iron compounds. In ground waters, the dissolved iron is usually in the ferrous bicarbonate state due to an excess of free carbon dioxide and is not filterable. Birm, acting as a catalyst between the oxygen and the soluble iron
com pounds, enhances the oxidation reaction of Fe++ to Fe+++ and produces ferric hydroxide which precipitates and may be easily filtered. The phys i cal characteristics of Birm provide an excellent filter media which is easily cleaned by backwashing to remove the precipitant. Birm is not consumed in the iron removal and therefore offers a tremendous economic advantage over many other iron removal methods.

Birm may also be used for manganese removal with the same dependability as iron removal. In these ap pli ca tions the water to be treated should have a pH of 8.0 to 9.0 for the
best results. If the water also contains iron, the pH should be below 8.5. High pH conditions may cause the formation of colloidal iron which is very difficult to filter out. All other conditions remain the same for either manganese or iron removal.

Advantages:
Under the proper conditions, no chemicals to pur chase
for maintenance. Regeneration not required.
Iron removal efficiency is extremely high
Negligible Labor Cost - only periodic
backwashing required
Durable material with a long life and wide
tem per a ture range
Weighs only 46-50 lb./cubic foot.

Physical Properties:
Color - Black
Density - 47-50 lbs./cu. ft.
Effective Size - 0.61 mm
Uniformity Coefficient - 1.72

Conditions for Operation:
Alkalinity should be greater than two times the
com bined sulfate and chloride concentration
pH - 6.8+
Dissolved Oxygen (D.O.) content must be equal to at
least 15% of the iron (or iron and manganese con tent)
Bed Depth - 30 - 36 in.
Backwash Rate - 10-12 gpm. sq. ft.
Backwash Bed Expansion - 35 -50% of bed depth
Service Flowrate - 3.5 - 5 gpm. sq. ft. intermittent flow
rates and/or favorable conditions may allow
higher flow rates