RSS Feed Print
Quaternary Ammonium Compounds
David Allen
Posted: Wednesday, May 18, 2011 5:24 PM
Joined: 5/18/2011
Posts: 2

We are having operational issues with a small activated sludge treatment plant that serves a truck stop with an in-store fast food restaurant.  We think this may be the result of improper usage of sanitizers, quaternary ammonium compounds in particular.  This is a small plant, average flow only 4,500 gallons per day.  Wanting to know if others have traced plant upsets to these sanitizers.

Victor Santa Cruz
Posted: Wednesday, May 18, 2011 8:53 PM
Joined: 11/11/2009
Posts: 38


Unfortunately, more than likely, you'll not get an answer here at the WEF Operation and Maintenance Forum.  There is a posting at www.waterandwastewater in regards to quaternary ammonia with quite a few responses.  Use the following link to view it:

This Forum is much more active.

Gary Sain
Posted: Thursday, May 19, 2011 6:53 AM
Joined: 4/8/2010
Posts: 9

David, some years back we noticed a degradation in a lagoon we used for an industrial facility.  Our first cell went from its usual healthy looking color to a grey dishwater appearance.  We ultimately traced it back to an onsite cafeteria that was doing chemical sanitation for dishwashing.  Part of the problem was that the cafeteria worker washing dishes had figured if the label called for a tablet of sanitizer, several would be great.


After we got the 'tablet feeder' calibrated, our problem went away. 

With your relatively small volume of water, I would think you could definitely see a problem with the sanitizer, particularly if they overuse the product. 

Posted: Monday, July 11, 2011 3:05 PM
Joined: 7/11/2011
Posts: 1

Worked with a small SBR facility that served a conference center.  Several years ago starting having problems with the facility.  Poor BOD/TSS removal and microscope indicated complete lack of protozoas.  Investigation found automatic quat compound dispensers recently installed in kitchen.  Further found kitchen staff had very little training or knowledge of how to use the sanitizers.  Final straw was when one of kitchen staff turned off auto feed to manual and forgot about it, needless to say the biomass was completely wiped out.  Finally convinced the kitchen manager to go with other less lethal sanitizers such as iodine, and have not a problem since.