Adjusting Temperature and Settling Time to Achieve ANAMMOX Particles Rapid Start-up and Stable Operation

Abstract

At room temperature (21-25℃), the long start-up time of anaerobic ammonium oxidation (ANAMMOX) granular sludge is the main problem preventing the practical application of this technology. This experiment aimed to cultivate the anaerobic ammonia oxidizing granular sludge in the SBR reactor by adjusting the temperature. After the start-up of the ANAMMOX, stable operation was achieved by changing hydraulic retention time (HRT) and the concentration of the inflow water substrate. The results demonstrated that the anaerobic ammonia oxidation granular sludge could be successfully started-up in 30 d and realized a stable operation at room temperature (21-25℃). The removal rate of ammonia-nitrogen and nitrogen was about 88% and 85%, respectively, and the removal rate of total nitrogen was 75%. At the stable operation stage of the low matrix, the removal rate of ammonia-nitrogen reached 86%, the removal rate of nitrogen was 98%, and the total nitrogen removal rate was over 85%. SVI was stable at 30 mL·g-1, and MLVSS/MLSS was more than 60%. The value of protein/polysaccharide was stable around 1.75. The dissolved oxygen in the influent was not removed. In this case, controlling the temperature could be used to realize the rapid start-up of the anaerobic ammonia oxidation granular sludge at room temperature (21-25℃), and the high biomass content and nitrogen removal rate can be obtained.