Flotation unit

Large particles are removed from the waste water in a flotation tank. Flotation units can be utilised to pre-treat waste water and/or in the separation phase of a decontamination process. Flotation units are often used in modern water purification processes due to their proven technology. Wazutec uses two types of flotation unit: Dissolved Air Flotation (DAF) and coalescence, also called coalescers.


Dissolved Air Flotation

Dissolved air flotation technology is characterised by the use of micro air bubbles to remove waste substances from the water. The use of these tiny air bubbles drives the contamination to the surface. The formation and distribution of the air and water are important to the process. The sludge (solid components) that are created at the top of the waste water are removed using a scraper. Following separation, the sludge is pushed or sucked into a separate reservoir. To increase the effectiveness of the separation of a DAF unit, Wazutec uses ELFLOX® technology, which is a patented electrochemical process, or the addition of chemicals. Wazutec does not use flotation sludge scrapers.



Coalescence is used in non-mixable or difficult to mix phases. These might be oily components and water. The flowing together of small and large droplets separates the waste water. This takes place in a tank containing plates. The droplets form larger droplets on the walls of the tank. Using coalescence, the oily components rise to the water surface, from where they can later be removed. Re-use of the organic phase is one of the possibilities.



  • Application: DAF units are very suitable in combination with micromembrane and ultra-membrane filtration systems or oil separation units
  • Operating costs: depending on the situation. Wazutec gladly calculates for you what the operating costs are in your situation.
  • Performance:
    – Coated steel St37, AISI304, AISI316 or higher plastic PP or HDPE
    – Pipeflocculator
    – Combined flotation sedimentation
  • Capacities: up to 150 m3 / h per unit

We would like to discuss with you what the most suitable flotation unit is for your waste water.