Jar testing for Oxidation of BOD/COD
Jar testing for Oxidation of BOD/COD
(OP)
Hi, folks,
I am going to be doing some jar testing to remove BOD/ COD from an industrial waste stream. BOD is about 1200 mg/L, COD 2000 mg/L. Need to knock this down to 300 mg/L BOD, 750 mg/L COD. Waste stream is small (5,000 gpd), so we're trying to avoid biological if possible.
We're looking at oxidizing with chlorine (sodium hypochlorite?) or peroxide. Also, looking at removal by activated carbon.
I'd love to have some words of wisdom on jar testing these kinds of things. e.g., concentration of chemicals, can we use an ORP meter, a general test procedure.
Any help out there from the gallery?
Thanks
I am going to be doing some jar testing to remove BOD/ COD from an industrial waste stream. BOD is about 1200 mg/L, COD 2000 mg/L. Need to knock this down to 300 mg/L BOD, 750 mg/L COD. Waste stream is small (5,000 gpd), so we're trying to avoid biological if possible.
We're looking at oxidizing with chlorine (sodium hypochlorite?) or peroxide. Also, looking at removal by activated carbon.
I'd love to have some words of wisdom on jar testing these kinds of things. e.g., concentration of chemicals, can we use an ORP meter, a general test procedure.
Any help out there from the gallery?
Thanks





RE: Jar testing for Oxidation of BOD/COD
In general, it will not be feasible to reduce the BOD significantly with chemicals. However, if you have floatables or solids, you may be able to remove some of it.
RE: Jar testing for Oxidation of BOD/COD
When the pH is dropped to about 3.5, about half of the BOD/COD comes out as a precipitant. The numbers I gave at first are after this step. We're trying to treat the rest of it.
RE: Jar testing for Oxidation of BOD/COD
About the only thing that may work is a catalytic oxidation process. Probably not economical either.
Have you considered an evaporation process?
RE: Jar testing for Oxidation of BOD/COD
The big downside to this approach is sludge production. You may be able to forego Step-3 if COD targets can be met without dragging out the adsorbed COD, in which case I'd raise the pH only enough to meet discharge requirements (pH 6?) so as to minimize Fe precipitation.
Just a reality check ... the chemical costs for should be in the range of $125 - 250 per day (5,000 gals WW).