Optimization of three-stage Anammox system removing nitrogen from landfill leachate.

•The mature landfill leachate used in this study was real instead of synthetic.•Effect of feeding mode and influent organics on Anammox was investigated.•Continuous feeding mode reduced inhibition of high influent substrates on Anammox.•A dose of COD improved nitrogen removal, and should be maintained below 800mg/L.