Iron Removal Filtration

An Iron Removal Filter (IRF) is a filtration system designed to remove excess iron and manganese from water, which can cause staining, metallic taste, and operational issues in plumbing and appliances. These filters are widely used in residential, industrial, and municipal water treatment systems.

Components of an Iron Removal Filter

1. Filter Vessel:
   • Made of materials like mild steel, stainless steel, or FRP (Fiber Reinforced Plastic) or Poly-glass.
   • Designed to withstand operational pressures.
2. Filtration Media:
   • Specialized media such as:
     • Manganese Dioxide, Greensand: Catalyzes oxidation of iron and manganese.
     • Birm: Requires dissolved oxygen for effective filtration.
     • Katalox Light, DMI 65, Purolite MZ plus
     • Sand and Gravel: Used as underbed
3. Aeration/Pre-Oxidation Unit (optional):
   • Injects air or oxidizing agents (e.g., chlorine or potassium permanganate) to oxidize soluble iron into insoluble particles.
4. Multi-port valve:
   • Top only or Top & Bottom.
5. Underdrain System:
   • Prevents media loss and ensures even distribution of flow.
6. Backwash System:
   • Cleans the media by reversing the flow to remove trapped particles.
7. Pressure Gauges:
   • Monitors pressure drop, indicating the need for cleaning or maintenance.

Working Principle

1. Oxidation:
   • Dissolved iron (Fe²⁺) is oxidized to insoluble ferric iron (Fe³⁺) using air, chlorine, or an oxidizing media.
2. Filtration:
   • Insoluble iron particles are trapped in the filtration media while clean water passes through.
3. Backwashing:
   • The trapped particles are removed by reversing water flow during backwash, restoring the filter’s efficiency.

Applications

1. Residential Water Treatment:
   • Removes iron from well water to prevent staining and improve taste.
2. Industrial Water Systems:
   • Protects equipment from iron deposits in boilers, cooling towers, and manufacturing processes.
3. Municipal Water Supply:
   • Ensures water quality for distribution systems.
4. Irrigation Systems:
   • Prevents clogging of drippers and sprinklers.

Advantages

• Efficient removal of iron and manganese.
• Improves water taste, clarity, and usability.
• Protects plumbing, appliances, and industrial systems.
• Requires minimal chemical inputs if catalytic media is used.

Limitations

• Pre-treatment may be required for high iron concentrations.
• Ineffective for iron in complex forms (e.g., organically bound iron).
• Regular maintenance and media replacement are necessary.