State of The Art Strategies for Successful ANAMMOX Startup and Development: A Review

Abstract

ANAMMOX (Anaerobic ammonium oxidation) bacteria, leading proponent of autotrophic ammonia removal, requires dedicated enrichment and cultivation techniques due to its slow growth rate and low biomass yield. Sensitivity to inhibitory concentrations of NO2--N, O2 etc., often present in industrial effluents makes ANAMMOX startup difficult to achieve. In this paper, significant parameters for ANAMMOX startup and development such as source of seed, type of reactors used, one and two stage ANAMMOX process, operational strategies and experimental conditions promoting long term enrichment, cultivation and quantitative analysis with biomass retention are discoursed in detail. Key chemical and molecular signatures including NO2 --N, Alkalinity, O2, Polymerase chain reaction (PCR), Fluorescence in situ hybridization (FISH), Scanning electron microscopy (SEM), inhibitors and affinity factors for ANAMMOX activity are deliberated. Summary of state of the art on ANAMMOX enrichment, recommendations for future research with specific contributions of this paper to scientific community is brought out in  conclusion.