JOURNAL ARTICLE
RESEARCH SUPPORT, NON-U.S. GOV'T
Add like
Add dislike
Add to saved papers

Total and stable washout of nitrite oxidizing bacteria from a nitrifying continuous activated sludge system using automatic control based on Oxygen Uptake Rate measurements.

Water Research 2009 June
Partial nitrification (ammonium oxidation to nitrite) has gained a lot of interest among researchers in the last years because of its advantages with respect to complete nitrification (ammonium oxidation to nitrate): decrease of oxygen requirements for nitrification, reduction of COD demand and CO(2) emissions during denitrification and higher denitrification rate and lower biomass production during anoxic growth. In this study, an extremely high-strength ammonium wastewater (3000-4000mg NL(-1)) was treated in a continuous pilot plant with a configuration of three reactors in series plus a settler. The system was operated under the maximum possible volumetric nitrogen loading rate, at mild temperature (around 25 degrees C), with high sludge retention time (around 30d) and significant nitrifying biomass concentration (average of 1800+/-600mg VSSL(-1)). The implemented control loops transformed the system, which was operating with complete nitrification, into a continuous partial nitrification system. Nitrite oxidizing bacteria (NOB) washout was accomplished with local control loops for pH and dissolved oxygen (DO) with proper setpoints for NOB inhibition (pH=8.3 and DO=1.2-1.9mg O(2)L(-1)) and with an inflow control loop based on Oxygen Uptake Rate (OUR) measurements, which allowed working at the maximum ammonium oxidation capacity of the pilot plant in each moment. This operational strategy maximized the difference between ammonia oxidizing bacteria (AOB) and NOB growth rates, which is the key point to achieve a fast and stable NOB washout. The results showed a stable operation of the partial nitrification system during more than 100 days and NOB washout was corroborated with fluorescence in-situ hybridization (FISH) analysis.

Full text links

We have located links that may give you full text access.
Can't access the paper?
Try logging in through your university/institutional subscription. For a smoother one-click institutional access experience, please use our mobile app.

For the best experience, use the Read mobile app

Mobile app image

Get seemless 1-tap access through your institution/university

For the best experience, use the Read mobile app

All material on this website is protected by copyright, Copyright © 1994-2024 by WebMD LLC.
This website also contains material copyrighted by 3rd parties.

By using this service, you agree to our terms of use and privacy policy.

Your Privacy Choices Toggle icon

You can now claim free CME credits for this literature searchClaim now

Get seemless 1-tap access through your institution/university

For the best experience, use the Read mobile app