Household Water Treatment and Safe Storage Factsheet: Source ...

Household Water Treatment for Fluoride Removal
Fact Sheet: Activated Alumina
Key Data
Inlet Water Criteria
The pH of the water should preferably be between 5 and 6; at a pH > 7 silicate and hydroxyl
ions become stronger competitors against fluoride ions for adsorption preference (Renu,
Singh and Maheswari, 2001)
Treatment Efficiency
Laboratory
Field
Bacteria Viruses Protozoa Helminths Turbidity Fluoride
Not
available
Not
available
Not
available
Not
available
Not
available
Not
available
Not
available
Not
available
Not
available
Not
available
90% in batch 1
up to 98% in
column 2
Not available
1 An initial fluoride concentration of 5 mg/L reduced to down to 1.4 mg/L before regeneration and to 0.5 mg/L on
regeneration with 2N HCl (Savinelli, 1958).
2 (Nakkeeran and Sitaramamurthy, 2007)
Operating Criteria
Flow Rate Batch Volume Daily Water Supply
Not available 1 Not available 1 Not available 1
1 Depending on filter type (WHO, 2006)
The flow rate, batch volume and daily water supply depend on the kind of filter used
Robustness
Taps can be broken and may need replacement
Activated alumina needs to be replaced or regenerated once saturated
It is necessary to measure the fluoride concentration in the outlet water to know when to
replace or regenerate media
Estimated Lifespan
Media regeneration every 6 months to 1 year
Estimation of the filter lifespan can be made based on the fluoride concentration of the raw
water, the daily volume through the filter and the adsorption capacity of the activated alumina
Manufacturing Requirements
Worldwide Producers:
Many producers around the world
Local Production:
Difficult and complex to manufacture, local production is not feasible
Maintenance
The regeneration cannot be left to the users: skilled labour is required to test the filtered water
and recharge activated alumina
The effluent from regeneration is high in fluoride and must be disposed of carefully to avoid
recontamination of nearby groundwater