A novel vertical dual-loop reactor for rapid start-up of simultaneous partial nitrification and anammox process in treating landfill leachate: Performances and mechanisms.

A novel vertical dual-loop reactor (VDLR) was developed to start and conduct a single-stage partial nitritation (PN) and anammox (PN/A) process for treating landfill leachate. Results showed that the total nitrogen (TN) removal reached 1.54 kg N/m3·d in the VDLR. It exhibited excellent mixing uniformity and buffer performance, which can increase the nitrogen removal performance up to 42.1 % via the improvement of anammox granular sludge activity (a particle size of 0.5-1 mm). Mass balance and microbial analysis indicated that the VDLR achieved efficient TN removal via anammox (99.24 %) and AOB (Nitrosomonas and Ellin6067) and anAOB (Candidatus kuenenia) played a vital role in this process.