Dissolved Air Flotation (DAF)
Dissolved Air Flotation (DAF)
DAF systems are used to remove suspended solids and liquids (such as oil) from water. To achieve separation, water saturated with air is pressurized and then introduced into an atmospheric floatation tank containing the produced water to be treated. The equalizing pressure causes the air to be released resulting in bubbles. These bubbles stick to the suspended particles and cause them to float to the surface. Once at the surface, the particles are skimmed off.
Process Description
A portion of treated produced water leaving the DAF tank is recycled and pumped to an air drum where the compressed air is introduced to the water. Sufficient air is introduced to ensure the water is air saturated. This air saturated water is then sent to the front floatation tank. When the water saturated with air is introduced to the floatation tank, tiny air bubbles are released. These air bubbles attach themselves to the particles that are to be removed causing them to rise to the surface of the tank. A skimmer or weir plate is utilized to segregate suspended particles and treated water. Typically, chemicals are injected into the feed water to flocculate the suspended particles. Additionally, natural gas may be used instead of air depending on the application and location of the facility. SPEC’s designed and manufactured DAF systems provide:
Efficient design
- Quick Start-Up and able to handle periodic stoppage
- Customized and standard packages
- Complete skid mounted packages
- ASME coded vessels
- Up to 90% removal of effluent and solid removal
- Minimal Chemical Usage
- Screw conveyor available for heavy solid removal