Fate and effect of benzalkonium chlorides in a continuous-flow biological nitrogen removal system treating poultry processing wastewater.
Quaternary ammonium compounds (QACs) are used for sanitation in many poultry processing facilities. This work investigated the fate and effect of a mixture of benzalkonium chlorides (BACs), a class of QACs widely used in commercial antimicrobial formulations, on the biological nitrogen removal (BNR) processes. A laboratory-scale BNR system was operated continuously for 670 days, fed with poultry processing wastewater amended with a mixture of BACs. Initially, the nitrogen removal efficiency deteriorated at a BAC feed concentration of 5 mg/L due to the complete inhibition of nitrification. However, after 27 days of operation, the system recovered and achieved 100% ammonia removal. High nitrogen removal efficiency was achieved even after the feed BAC concentration was stepwise increased up to 120 mg/L. Batch nitrification assays performed before, during, and after BAC exposure, showed that rapid microbial acclimation and BAC biodegradation contributed to the recovery of nitrification achieving efficient and stable long-term BNR system operation.
School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30332-0512, USA.
Malek G
MG
Hajaya
Spyros G
SG
Pavlostathis
D000332:Aerobiosis; D000388:Air; D000818:Animals; D061249:Batch Cell Culture Techniques; D001548:Benzalkonium Compounds / Q000302:isolation & purification*; D001673:Biodegradation, Environmental; D019149:Bioreactors / Q000382:microbiology; D058440:Denitrification; D005285:Fermentation; D058465:Nitrification; D009584:Nitrogen / Q000302:isolation & purification*; D011200:Poultry; D012212:Rheology; D013997:Time Factors; D014865:Waste Disposal, Fluid; D018508:Water Purification / Q000379:methods*
D001548:Benzalkonium Compounds; D009584:Nitrogen