Performance and microbial ecology of a novel moving bed biofilm reactor process inoculated with heterotrophic nitrification-aerobic denitrification bacteria for high ammonia nitrogen wastewater treatment.

To overcome long start-up time, poor ammonia tolerance and removal performance of traditional moving bed biofilm reactor (MBBR) inoculated with activated sludge for high-ammonia wastewater treatment, a novel MBBR based on heterotrophic nitrification-aerobic denitrification (HN-AD) was proposed. Start-up of MBBR was firstly performed via inoculated with HN-AD bacteria. Start-up time was shortened from 39 d to 15 d, NH ₄ ⁺ tolerance was enhanced from 200 mg/L to 1000 mg/L, and TN removal was increased from 30.4% to 80.7%. The carrier types and NH ₄ ⁺ concentration had significant effects on nitrogen removal and microbial ecology. When the NH ₄ ⁺ concentration was increased to 900 mg/L in MBBR using polyvinyl alcohol gel as carrier, the TN removal, the abundance of HN-AD bacteria Acinetobacter, Pseudomonas and Paracoccus, which played a key role in TN removal and ammonia tolerance, and the abundance of genes related to nitrogen removal were much higher than those of MBBR using kaldness.
Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
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