Arsenic Removal/Filter

[Tedops]

We have had a change in our water dicharge permit recently, not allowing any levels of arsenic to be present in our waste stream. Our water source comes from Two 50' deep wells. water is used for Cooling Tower Make-up. The Cooling Tower then blows down to what is now a settling pond and then into a major waterway. Currently we blowdown about 70 gpm. The new discharge permit does not allow us to discharge any arsenic back on to the ground. I need to find a way to remove this arsenic either at the well head (preferred) or at the blowdown discharge point. Is there such a thing as an arsenic filter or some sort of resin bed that will remove this arsenic. I got to imagine someone has run into this before....yes? Thanks for any help.

 

[GarySCWSVI]

There are numerous media that are used to remove arsenic. My favorite is an ion exchange/adsorbent called ARSENXnp. One can also use a standard Strong Base Anion exchange resin or a Ferric Iron adsorbent. Ask most any media supplier. These days virtually all of them offer something.

Gary Schreiber, CWS VI
The Purolite Co.

 

[francesca]

On October 31, 2001, the EPA Administrator announced that the 10 ppb (0.010 mg/L) standard for arsenic would remain stating that, "the 10 ppb protects public health based on the best available science and ensures that the cost of the standard is achievable."

The above quote comes from the EPA website].

Arsenic is a carcinogen, so EPA policy goal is "no arsenic in the drinking water," however, it is not possible to measure arsenic reliably below 10 ppb, so the EPA regulates at that level.

I don't know where you're located, but zero arsenic in your effluent is impossible to achieve, and impossible to confirm by measurement.

 

[Bjegovic]

this makes little sense because you are discharging the same water you are taking from wells. but yes, regulations can be tricky!

70 ppb of arsenic however is quite usual concentration in raw water.

however, if you have to reduce it to 10 ppb prior to discharge, I reccomend 2 stage filtration with dosing of ferric sulphate / chloride salts to enhance arsenic removal.

last year we have built 400 l/sec potable water treatment plant, with 100 ppb arsenic on the inlet, and treatment is 2 stage filtration on mineral multimedial filters.

If you use adsorption media, you will have to replace it 3-4 times per year or so! it wil cost you a lot of money...