Merely inoculating anammox sludge to achieve the start-up of anammox and autotrophic desulfurization-denitrification process

Abstract

Anammox and autotrophic desulfurization-denitrification (AADD) process is feasible for the nitrogen and sulfide removal in the same reactor, and the influence of excess nitrate produced by anammox could also be alleviated simultaneously. This study firstly proposed a novel strategy with inoculating single anammox sludge to start up the AADD process. Results demonstrated that the 90% nitrogen removal efficiency (NRE), 2.55kgm−3 d−1 nitrogen removal rate (NRR), and 95% sulfide removal efficiency (SRE) were obtained at the influent total nitrogen of 280mgL−1 and sulfide of 221.5mgL−1, and the final effluent nitrate concentration was as low as 8mgL−1 under the appropriate operation conditions. Tryptophan-like and protein-like substances were characterized as the main components in bound EPS. Thiobacillus (35.68%) and Pseudoxanthomonas (11.61%) were identified as the predominant genera. This study will pave a potential avenue to promote the treatment of high concentration nitrogen and sulfide in wastewater in the future.