Synchronous rapid start-up of the methanation and anammox processes in two-stage ASBRs

The "methanation + anaerobic ammonia oxidation autotrophic denitrification" method was adopted by using anaerobic sequencing batch reactors (ASBRs) and realized a satisfactory synchronous removal of chemical oxygen demand (COD) and ammonia-nitrogen (NH₄ ⁺-N) in wastewater after 75 days operation. 90% of COD was removed at a COD load of 1.2 kg/(m³•d) and 90% of TN was removed at a TN load of 0.14 kg/(m³•d). The anammox reaction ratio was estimated to be 1: 1.32: 0.26. The results showed that synchronous rapid start-up of the methanation and anaerobic ammonia oxidation processes in two-stage ASBRs was feasible. (paper)