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 pressurized water treatment systems. Birm acts as an insoluble catalyst to enhance the reaction between dissolved oxygen (D.O.) and the iron compounds. In ground waters, the dissolved iron is usually in the ferris 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 compounds, enhances the oxidation reaction of Fe++ to Fe+++ and produces ferric hydroxide which precipitates and my be easily filtered. The physical characteristics of Birm provide an excellent filter media which is easily cleaned by backwashing to remove the precipitant. Birm in 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 applications 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 purchase 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 temperature 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 combined sulfate and chloride concentration.
• pH - 6.8+
• Dissolved Oxygen (DO) content must be equal to at least 15% of the iron (or iron and manganese content)
• Bed Depth - 30 - 36 in.
• Backwash Rate - 10-12 gpm. sq. ft.
• Backwash Bed Expansion - 35-50% space of bed depth
• Service Flowrate - 3.5 - 5 gpm. sq. ft. intermittent flow rates and/or favorable conditions may allow higher flow rates.