Mixed liquor recirculation

Solutions for efficient nitrogen removal

When denitrification is followed by a physically separated nitrification step, the nitrates formed during nitrification must be recirculated. The nitrates are pumped back into the denitrification step, where the anoxic process splits the nitrate molecules into nitrogen and oxygen. This frees the nitrogen into the air.

The correct recirculation of nitrates, referred to as mixed liquor recirculation, is naturally essential for highly efficient nitrogen removal. This application is best served by submersible recirculation pump types ABS XRCP and RCP, the submersible mixed flow column pump type ABS AFLX and the submersible propeller pump type ABS VUPX.