. . . that on January 2006, the EPA lowered the maximum contaminant level in drinking water from 50ppb to 10ppb in drinking water?
More than 4000 water utilities serving approximately 20 million people need corrective action to comply with these new regulations. A majority of the small and medium size drinking water utilities require an arsenic removal system that is easy to operate, low cost, requires minimal operator attention or training, flexible within fluctuation in feed compositions, does not require frequent regeneration or disposal, and requires minimal start up time. A fixed bed HIX arsenic removal system meets all of the above desirable attributes and is ideal for use by the small and medium utilities required to comply with the 10ppb standard for total arsenic.
Hybrid Sorbent (HIX) for Arsenic Removal
VEETech, P.C. in collaboration with Lehigh University developed and tested polymeric-inorganic hybrid sorbents or HIXs for removal of arsenic from drinking water.
HIX exhibits the following characteristics for removal of arsenic in drinking water
- Excellent mechanical strength and attrition resistance
- Selective towards both As (III) and As (V)
- Does not require pre- or post-treatment (e.g. pH)
- Does not alter electrolytic quality of treated water
- Does not generate fines or pressure drops during long term column operation
- Efficiency is not affected by the presence of high concentrations of silica, phosphate or sulfate in water
- Can treat up to 40,000 bed volume (BV) of water/cycle
- Can be regenerated up to 20 to 30 cycles of operation
- Can remove multiple contaminants such as Ra, U, and perchlorate along with arsenic
Sources of Arsenic
Inorganic arsenic, which occurs as As(III) or As(V) in drinking water, poses great threat to public health. In recent years, the presence of dissolved arsenic in contaminated groundwater has emerged as a major concern for drinking water supply on a global scale. The following are sources of dissolved arsenic in groundwater:
- Volcanic activity
- Natural geochemical contamination through soil leaching
- Insecticides and fungicides
- Combustion of fossil fuels
- Mining activities
Exposure to higher levels of arsenic in drinking water can cause:
- Thickening and discoloration of skin
- Nausea and diarrhea
- Decreased production of blood
- Skin cancer and tumors of the bladder, kidney, liver and lungs
The technologies that are available in the marketplace to remove arsenic from drinking water are
- Granular Ferric Hydroxide (GFH)
- E33 Granular Ferric Oxide (GFO)
- G2 Ferric Oxide Treated Diatomite
- Apyron Aqua-Bind SP60
- Hybrid Sorbent (HIX)
Of these media, only G2 and HIX are regenerable. The other media are good for once through application only.
HIX offers the following benefits over G2 for arsenic removal:
- HIX has greater uniformity using a polymeric resin bead as carrier
- HIX is not pH sensitive
- HIX can treat far greater bed volumes
- HIX is more robust and structurally rigid
- HIX offers lower unit and life cycle costs
