A single Multiphase “DAF Pump” is capable of replacing the entire air bubble system on DAF (Dissolved Air Floatation) plants, using EDUR Multiphase pumps supplied by Hydro Innovations. Their Edur® “Multiphase” pumps draw in air through a “snorkel” in the suction line, sheer the air, then feed it into the DAF plant. This produces a discharge stream into the tank that is saturated with 30 to 50 micron air bubbles.
Conventional DAF systems normally consist of a wastewater tank, compressor, air saturation vessel, and effluent pump. The effluent pump draws effluent from the tank and pumps it into the air separation vessel. A compressor pumps air into this same vessel. The air/water mixture is “saturated” under pressure, then released back into the wastewater tank at atmospheric pressure where tiny bubbles form and adhere to the suspended matter (fats, oils and other small wastewater particles). The bubbles (with their attached suspended matter) float to the surface of the tank, where floatables can be skimmed off the surface.

By using Edur® Multiphase pumps, which produce their own micro-bubbles, asset owners can do away with the compressor, the air saturation vessel and any control and/ or ancillary components for these items. The reduction of these system components and the simplification of the system design results in lower investment costs and higher operational reliability. The result in savings can add up to over 50% when you take into account the savings in capital equipment costs and related ongoing maintenance.
The Edur® Multiphase (DAF) pump is also an energy-efficient alternative. Now, one pump can replace the conventional pump, air saturation tank, and the compressor. Energy costs [as well as maintenance costs] of running the compressor are eliminated.
Edur® multiphase pumps can deliver flows from 1 l/s (for smaller DAF plants) to 15 l/s (for larger DAF plants) and produce pressures to 12 Bar. A variety of materials and seal arrangements enable Edur® pumps to operate in a very wide range of applications. Available materials include ductile iron, “gunmetal” bronze, stainless steel and super duplex. Mechanical seals available as balanced, double and tandem.