Wastewater Technology in New England, USA

This process is seasonal. It will not work in the winter unless you heat the process.

WWTP's in CT must still reduce nitrogen as much as possible, winter notwithstanding. Very few plants are indoors or covered. It is recognized that plants are less successful at removing nitrogen in cold weather. Running with a higher solids content in winter is one way of "tweaking" the process. I am looking for other possibilities. Actually, heating mixed liquor is not a bad idea. I'm just not sure how to go about doing it: are there such things as submersible heaters?

Thanks for your help and interest.

Terrific. Thank you.

What form is the N₂ in? If it is in NH₃ form, very vigorous aeration can remove it. If it is in NO₃ form, heating the water to stimulate the activity of bacteria to denitrify it or the use of plants in a heated environment will also work.

Removing NO3 is the focus of the process. Are there submersible heaters?

This process is called denitrification. Nitrification converts ammonia to nitrite and nitrite to nitrate and that's it. Denitrification converts nitrate to nitrogen gas. This is done in the anoxic zone of an oxidation ditch or by the Bardenpho four-stage process.

If the process train is such that no carbon is present in the denitrification reactor, then methanol will have to be added. This will be expensive.