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  for Metal Finishing since 1989
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C o d reduction

Occasionally we have problems overshooting our c o d limits in our final waste water discharge. I am told that ozone can be used to reduce c o d. is there anyone in metal finishing familiar with this process?.
How dose it work?, is it successful?.

Vinnie Mc Guinn
Lock Manufacture - Ireland
2005

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I'm not familiar with ozone for this purpose, but you can add hydrogen peroxide to reduce COD.

Jeffrey Holmes, CEF
Spartanburg, South Carolina
2005

Ammonium phosphate can produce algae that can lower cod.

Teody Delgado
- Manila, Philippines
2006

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Any strong oxidizer, such as ozone, peroxide,or peroxide plus UV light, can reduce COD under the right conditions and with enough reaction time.

To know the right conditions, however, you need to know a little more about what chemical(s) are causing the high COD, and whether they are dissolved or suspended solids.

Lyle Kirman
consultant - Cleveland Heights, Ohio
2006

I agree with Lyle, UV plus oxidising agents will reduce COD load to a large extent. there are instances where COD of value more than 20000 are reduced to 300 instantaneously.

Aravind A Narayan
- Coimbatore, Tamilnadu, India
2006