VLR® System for Biological Treatment

VLR® Systems from Evoqua utilize a vertical loop based design with looped reactors in series that allows DO stratification. As such, it is suited for simultaneous nitrification/denitrification; biological phosphorus removal and storm water treatment.

Envirex® Vertical Loop Reactor
VLR® System
The VLR® system tanks are similar to oxidation ditches that have been flipped on their sides.  There is an upper and lower compartment, separated by a horizontal baffle running the length of the tank.  The process has been adapted from our proven Orbal® Multichannel Oxidation Ditch technology and uses the same surface mounted discs to provide mixing and deliver oxygen.  Typically, two or more basins make up the system, with the first tank operating as an aerated anoxic reactor.

Features and Benefits

  • Common wall construction – lower construction costs
  • Small footprint – less land area required
  • Dual aerator design – operating flexibility
  • Lengthy aeration retention time  – low power costs
  • Coarse bubble diffusers – easy to meet peak oxygen demands
  • DO stratification – process adaptability
  • Handles excessive storm water treatment – peak flows five times the design flow