Feasibility of anaerobic ammonium oxidation process for treatment of pretreated printed circuit board wastewater

The treatment of pretreated printed circuit board (PCB) wastewater by anaerobic ammonium oxidation (anammox) process has been rarely reported. This study sought to investigate the performance of the anammox process during various phases of pretreated PCB wastewater treatment. The nitrogen removal efficiency (NRE) reached 90 ± 10% at a Cu2+ concentration of 2.5 mg·L-1, but declined to 22 ± 11% as the Cu2+ level increased to 10.3 mg·L-1. During phase III, there was a 38% increase in the relative abundance of Candidatus Kuenenia compared to phase I. By adjusting the substrate concentration and introducing synthetic wastewater into the reactor, the anammox performance was nearly restored to that of phase I. These findings underscore the potential of the anammox process for treating pretreated PCB wastewater and expanding its practical applications to industrial wastewater treatment.