Rapid start-up of nitrifying MBBRs at low temperatures: nitrification, biofilm response and microbiome analysis.
The moving bed biofilm reactor (MBBR), operated as a post carbon removal system, requires long start-up times in comparison to carbon removal systems due to slow growing autotrophic organisms. This study investigates the use of carriers seeded in a carbon rich treatment system prior to inoculation in a nitrifying MBBR system to promote the rapid development of nitrifying biofilm in an MBBR system at temperatures between 6 and 8 °C. Results show that nitrification was initiated by the carbon removal carriers after 22 h of operation. High throughput 16S-rDNA sequencing indicates that the sloughing period was a result of heterotrophic organism detachment and the recovery and stabilization period included a growth of Nitrosomonas and Nitrospira as the dominant ammonia oxidizing bacteria (AOB) and nitrite oxidizing bacteria (NOB) in the biofilm. Peripheral microorganisms such as Myxococcales, a rapid EPS producer, appear to have contributed to the recovery and stabilization of the biofilm.
Department of Civil Engineering, Faculty of Engineering, University of Ottawa, 161, Louis Pasteur, Ottawa, ON, K1N 6N5, Canada.
Bradley
B
Young
Department of Civil Engineering, Faculty of Engineering, University of Ottawa, 161, Louis Pasteur, Ottawa, ON, K1N 6N5, Canada. robert.delatolla@uottawa.ca.
Robert
R
Delatolla
Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, Canada.|Department of Medical Technology, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia.
Turki
T
Abujamel
Department of Civil Engineering, Faculty of Engineering, University of Ottawa, 161, Louis Pasteur, Ottawa, ON, K1N 6N5, Canada.
Kevin
K
Kennedy
Veolia Water Technologies Canada, Montreal, QC, Canada.
Edith
E
Laflamme
Department of Biochemistry, Microbiology and Immunology, Faculty of Medicine, Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, Canada.
Alain
A
Stintzi
D018441:Biofilms / Q000254:growth & development*; D019149:Bioreactors / Q000382:microbiology*; D064307:Microbiota / Q000502:physiology*; D009231:Myxococcales / Q000502:physiology*
Ammonia removal; Biofilm morphology; MBBR; Next generation sequencing; System start-up