Sour Water, Foaming and Aeration

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Sour Water, Foaming and Aeration

QUESTION

We have been dealing with an upset condition at our facility due to having to treat some stored sour water inventory. The water is high in sulfides (136 ppm) and sulfite (247 ppm). We are running all of our aeration equipment at full capacity. We are starting to see foaming issues and very low D.O. levels. We have added some totes of peroxide and can see that it is helping but are concerned adding too much could kill our biological population. Our aeration capacity is 5 million gallons. The sour water stream is about 50 gpm. Any recommendations on adding more peroxide?  Dan P, Wastewater Engineer.

ANSWER

It is difficult to get enough aeration equipment in the right location to treat the added sulfide/sulfite load on your system. The result of over aerating the front of the plant is often foaming. Hydrogen peroxide can be added directly to the influent of your aeration basin to oxidize the sulfide/sulfite load. H2O2 is immediately catalyzed and provides a 100% transfer of oxygen to your basin. This is very efficient compared to most aerators that are transferring oxygen at around 25-40%. Sometimes lower if influent temperatures are above 100° F. There is no harm to your biology. The result is by adding enough h2o2 to treat the overloading of sulfide/sulfite, your aeration basin should see a rise in D.O. fairly quick and will be able to handle to normal plant load coming in.

Dan, I hope this helps answer your questions about how hydrogen peroxide can be applied safely and reliably provide supplemental dissolved oxygen.  Give our Applications Team a call at  (877) 346-4262 if you want to discuss this in more detail or want one of our technical team to visit your site for a technology fit assessment.

Sincerely,

USP Technologies Wastewater Technology Group