WPL Dissolved Air Flotation (DAF)

The WPL Dissolved Air Flotation (DAF) wastewater treatment plant is typically used in a wide range of industrial applications to mitigate the financial impact of trade effluent charges, and maintain environmental compliance. The WPL DAF wastewater treatment system is widely used for the reduction of Chemical Oxygen Demand (COD) present in fats, oils and greases, colour, organic matter, biological sludges and colloidal material.

The WPL DAF process has also been successfully applied to sensitive industrial applications, such as petrochemical, chemical production, pharmaceutical, waste reception facilities and paper production. The WPL DAF is ideal for new projects and existing plant upgrades.


Why you should choose the WPL DAF Treatment System:


  • Optimised chemistry, using our own in-house experts and laboratory.
  • Energy efficient treatment of wastewater.
  • Higher quality effluent discharged to sewer, further reducing costs.
  • Reduced sludge volume with higher dry solids content.
  • Can be used for recovery and recycling of non-emulsified oils with no further treatment required.

Low maintenance

  • Reinforced plastic components reduce wear and corrosion.
  • White water system utilises a pressure vessel to negate the need for diffusers within the floatation tank.

Small footprint

  • Only requires a small footprint in comparison to other technologies.


  • Fully integrated treatment package for adaptation into existing process streams.
  • Multiple systems installed in parallel for higher or variable flows.
  • Discreet independent modules for each element of the process train.
  • Transportable and fitted on site with a ‘plug and play’ approach to design, with options for access and portability.
  • Full dosing packages to compliment DAF performance if required.


  • Constructed in grade 304 or 316 stainless steel, with flocculation and coagulation units manufactured in MDPE to ensure an extended life and reduce risks of corrosion.
  • Manufactured to the highest European norms.

Reduced operational input

  • Fully automated control system, removes the need for manual operation.
  • Can be integrated with site BMS (building management systems).
  • Full integrated monitoring of final discharge to sewer or further treatment.


  • Multiple chemical injection and sampling points, manufactured to customer requirements.
  • Chemical dosing regime designed by WPL to meet the site requirements.


  • CE marked.
  • Built to European norms.

Typical industrial wastewater applications include:

  • Abattoirs, meat and poultry wastewater treatment
  • Brewery, winery and soft drink manufacture wastewater treatment
  • Baking and confectionery, ready meals and vegetable production and packaging manufactures wastewater treatment
  • Commercial laundry wastewater treatment
  • Cosmetics manufactures production and packaging wastewater treatment
  • Dairy inc milk, cream, yoghurt and cheese processing and packaging wastewater treatment
  • Fish processing wastewater treatment
  • Paper mills wastewater treatment
  • Petrochemical wastewater treatment
  • Pharmaceutical wastewater treatment
  • Textile manufacture wastewater treatment
  • Waste recycling centre wastewater treatment


The WPL DAF system is ideal for:

  • New projects
  • Existing plant upgrades
  • Replacement plants

Technical specification

For technical specification information (including indicative drawing), please download  the WPL DAF datasheet (available on this page).

How does a Dissolved Air Flotation (DAF) system work?

The WPL Dissolved Air Flotation system is a purely physical process which operates on a simple design philosophy. Incoming effluent may require pre-treatment as necessary; for example the addition of chemical coagulant(s) and/or flocculant(s) may be required. Adjustment of pH may also be necessary to ensure optimum operating conditions.

Process diagram of the WPL DAF wastewater treatment


(A) The incoming effluent enters the flotation vessel where it comes into contact with recycled, treated effluent (sometimes termed white water). The percentage of the total effluent flow into which air is dissolved under pressure and subsequently recycled will be determined by effluent specific factors.

(B) Once this saturated effluent enters the flotation tank, the pressure is released back to atmospheric. This immediately results in the recycled flow becoming supersaturated, generating micro bubbles as the dissolved air comes out of solution.

(C)These micro bubbles attach to the solids or chemical flocculants entering the vessel, causing them to float to the surface where they are retained and subsequently removed by a mechanical skimmer.

(D1) Within the rectangular flotation tank, the skimmer mechanism consists of a series of paddles or flights which run on a plastic corrosion-resistant chain, and skim just below the surface of the tank removing the float into a trough for recovery. To eliminate the risk of sludge build-up on the flotation tank floor, the design may also incorporate a floor scraper on larger systems.

(D2) Where solids normally sink, they collect in the hopper and are removed via a manual or automated valve, dependent on the effluent.

(E) The final treated effluent discharges to either drain or for further treatment.


Why industrial wastewater treatment is as challenging as it is varied?

Simon Kimber, discusses why industrial wastewater is as challenging as it is varied, which is why careful assessment and customised solutions are required.

Industrial processes can produce effluents that are challenging in terms of their strength, variability and composition. Careful assessment of the physical, chemical and biological characteristics of the load can deliver a cost-effective and efficient treatment process.

Read full article

Image of WPL dissolved air flotation DAF wastewater treatment tank with engineer