• Blog
  • Wastewater Testing
  • Bioaugmentation Applications
  • Useful Information
  • About Us
BIOLOGICAL WASTE TREATMENT EXPERT
Contact Us

Can ammonia be higher than TKN in wastewater?

1/15/2018

 
The answer is ----- NO. 

The reason TKN is always is higher than ammonia is related to what the test does. TKN or Total Kjeldahl Nitrogen uses sulfuric acid & catalysts to convert organic nitrogen to ammonia/ammonium. So in the digestion step - we have organic nitrogen such as proteins and amines being converted to ammonium (the digestion step is an acid where ammonia exists as ammonium). The test does not measure nitrate, nitrite, azo groups or nitrogen in ring structures.

Once digested - the sample pH is increased and tested for ammonia. The reading from the sample is total nitrogen. A non-digested sample is also tested for ammonia (using ISE or other ammonia testing method). The non-digested sample gives the ammonia/ammonium concentration.

TKN = total nitrogen (organic nitrogen converted to ammonium in acid digestion step)
Ammonia = increase pH to convert ammonium into ammonia - then read ammonia concentration

TKN - Ammonia = Total Organic Nitrogen (this gives the potential ammonia that can be released as organisms degrade proteins, amines, and other forms of organic nitrogen). Total Organic Nitrogen is abbreviated to TON. 

How can a lab have higher ammonia than TKN - it could be error in testing. Or dilution factors required for testing make the error term larger than the difference in TKN/Ammonia - this would require the sample contain mostly ammonia with little organic nitrogen.
Ludwing
1/30/2018 02:52:32 pm

Thanks! .

Miguel
3/26/2019 08:46:52 am

Thank you. I have also been trying to understand how the NH3 increases at the clarifier(150ppm) compared to the NH3 leaving the NH3 stripper bottoms(50ppm)


Comments are closed.

    Author

    Erik Rumbaugh has been involved in biological waste treatment for over 20 years. He has worked with industrial and municipal wastewater  facilities to ensure optimal performance of their treatment systems. He is a founder of Aster Bio (www.asterbio.com) specializing in biological waste treatment.

    View my profile on LinkedIn

    RSS Feed

    Click to set custom HTML

    Archives

    December 2022
    November 2022
    October 2022
    September 2022
    August 2022
    June 2022
    May 2022
    March 2022
    February 2022
    January 2022
    November 2021
    October 2021
    September 2021
    August 2021
    June 2021
    April 2021
    March 2021
    February 2021
    December 2020
    November 2020
    October 2020
    September 2020
    August 2020
    July 2020
    June 2020
    May 2020
    April 2020
    March 2020
    February 2020
    January 2020
    December 2019
    November 2019
    October 2019
    September 2019
    August 2019
    July 2019
    June 2019
    May 2019
    April 2019
    March 2019
    February 2019
    January 2019
    December 2018
    November 2018
    October 2018
    September 2018
    August 2018
    July 2018
    June 2018
    May 2018
    April 2018
    March 2018
    February 2018
    January 2018
    December 2017
    November 2017
    October 2017
    September 2017
    August 2017
    July 2017
    June 2017
    May 2017
    April 2017
    March 2017
    February 2017
    January 2017
    December 2016
    November 2016
    October 2016
    September 2016
    August 2016
    July 2016
    June 2016
    May 2016
    April 2016
    March 2016
    February 2016
    January 2016
    December 2015
    November 2015
    October 2015
    September 2015
    August 2015
    July 2015
    June 2015
    May 2015
    April 2015
    March 2015
    February 2015
    January 2015
    December 2014
    November 2014
    October 2014
    September 2014
    August 2014
    July 2014
    June 2014
    May 2014
    April 2014
    March 2014
    February 2014

Proudly powered by Weebly
Photos used under Creative Commons from Picturepest, marcoverch, perzonseowebbyra, Picturepest, Picturepest, dsearls, dungodung, Massachusetts Office of Travel & Tourism, aqua.mech, vastateparksstaff, hile, Aaron Volkening, amishsteve, Neil DeMaster, mklwong88, KOMUnews, Picturepest, kaibara87