MetSorb® Arsenic Filter Media
MetSorb HMRG arsenic media is used to reduce arsenic contamination from drinking water. Arsenic is a grey, semi-metal element. Arsenic enters ground water from both natural sources and human activity. Contamination can sometimes be traced to deep-water brines produced from gas and oil well drilling. It is also be found in wood preservatives and may be a byproduct of herbicide production.
MetSorb adsorbs lead, both forms of arsenic and a variety of contaminants found in well water or municipal drinking water. Empty bed contact times (EBCT) can as low as 10 seconds achieve high removal efficiencies. Its adsorptive capacity is 7-12 grams of arsenic per kilogram (g/kg) of HMRG adsorbent in drinking water applications with a pH range of 6.5-8.5. In industrial applications much higher capacities have been measured – up to 400 g/kg.
- MetSorb maintains a higher capacity and a lower level of ion interference than competitive iron and alumina based products. Unlike ion exchange resin it holds onto the ions rather than exchanging ions.
- Selectivity – it will remove arsenic III and arsenic V. On Arsenic III you get about 60% less life. At startup it will be non-detect and it picks up more arsenic III than any other media currently on the market.
- A full water analysis is required before applying the media. Iron and manganese will take up HMRG sites so it’s better to pre-treat for them. Pre-treatment with a water softener will remove the iron but the HMRG likes hard water. Soft water will reduce at least 15% of bed life.
If you use Greensand, Katalox Light or Pyrolox Advantage type medias for iron removal, the iron can complex with the arsenic and be removed. However, be careful of the capacity or loading factor. Greensand like products will not hold the arsenic forever. These iron filters will change the arsenic III to V so you can take full advantage of the MetSorb capacity.
Metsorb HMRG Specifications
White Granular Solid
Moisture Content <7%
Bulk Density 40 lbs. per cf
Other Free Flowing
Particle Size -16/+60 US Mesh
MetSorb HMRG Features & Benefits
- Nonhazardous disposal as solid waste
- High adsorbent capacity resulting in less frequent replacement
- Works effectively at high flow rates
- Metsorb HMRG is manufactured by Graver and is NSF Certified (NSF Listing below)
- No regeneration chemicals required
- Reduced and (in some cases eliminated) frequency of backwash
- Reduced equipment footprint
- Simple installation & startup
- Extremely fast kinetics: generally 1.5 to 3 minutes empty bed contact time (EBCT)
- Empty Bed Contact Time is 1.5 to 3 minutes which is extremely fast. Smaller tanks can be used.
- At 50ppb a lead lag system is required.
- Backwash upon start up and periodically to fluff the bed and prevent channeling.
- Backwash at 4 gpm per ft2 or 2.4 gpm in a 10” tank.
- If using a single tank include a no hard water bypass to shut off the water while the unit is in backwash. Otherwise use twin backwashing systems.
- MetSorb does not release contaminants during backwash.
- Like GAC, bacteria may build up on MetSorb and cause an odor problem. If this happens use chlorine or hydrogen peroxide to shock the bed and kill the bacteria. This should become part of a regular maintenance schedule.
- pH has no effect on MetSorb. It will not desorb but it favors a lower pH. Obviously, not lower than 6.5 but not 8 or 8.5.
- Laws do not regulate the disposal of MetSorb used in point of use or point of entry systems.
- For larger municipal applications, treating hundreds or thousands of gallons per minute, a TCLP (Toxicity Characteristic Leaching Procedure) is required.
- MetSorb will not release contaminants into the ground.
- Any job with a DEP focus, where paperwork must be filed be sure to observe all the governing rules. Chain of Custody is critical in these situations.