Dissolved Air Flotation Process in Wastewater Treatment
Written by AOS Treatment Solutions on February 13, 2018
What Is Dissolved Air Flotation Water Treatment?
Dissolved air flotation (DAF) is a water treatment process designed to remove oils, solids, and greases. In fact, the process helps clarify wastewaters – and other waters – by eliminating different types of suspended matter. The DAF process dissolves air in the water under pressure – then releases it at atmospheric pressure. The dissolved air flotation process takes place in a tank basin, which is ideal for catching and eliminating suspended matter. In fact, the released air creates tiny bubbles, which conform to the suspended matter and cause it to rise to the surface. Skimmers or a similar device then eradicate the substance.
Dissolved air flotation design is instrumental in effective water treatment. This process is also widely used in several industries and sectors, including but not limited to:
- Removing particles and treating industrial wastewater effluents at oil refineries.
- Water treatment processing for petrochemical and chemical plants.
- Water filtration for fuel gas conditioning plants and paper mills.
- Industrial facilities requiring wastewater treatment for daily protocols or project-related processes.
The Dissolved Air Flotation Process
Dissolved air flotation process for water clarification occurs in a float tank dosed with a coagulant – such as aluminum sulfate or ferric chlorides. The coagulant enables the particles to form larger clusters for safe and effective removal. Water leaving the DAF tank is pumped into a pressure vessel (air drum) where the compressed air is present, resulting in saturation of the pressurized water with air. The saturation results in the formation of tiny bubbles that trap oils, solids, and greases. The bubbles form on the surface of the suspended matter particles, which then float to the surface, creating froth layers that are removed by skimmers.
There are different types of DAF units and designs on the market today. These include:
- Lamella clarifiers offer more separation surfaces for effective wastewater treatments.
- DAF systems feature circular units, which are more efficient and thorough.
- DAF systems also have rectangular units, which secure more residence time.
- The flotation process in wastewater treatment plays a pivotal role in meeting environmental discharge compliances and regulations.
Dissolved Air Flotation Systems for Water Treatments
Dissolved air flotation is a process utilized across a myriad of industries. In fact, water or wastewater treatment creates mineral and organic sludges from filtration. Similarly, the process produces these kinds of sludges from sedimentation as well. The primary purpose, of course, is to remove magnesium, calcium, and carbonate ions from water and to replace them with other ions, including chloride, sodium, and hydroxyl.
Wastewater treatments exist for recycling or re-use in several industries. Remember, it is essential for water entering and leaving industrial plants to meet all governing criteria and rules. These requirements prevent contamination of local drinking sources while ensuring any recycled water is adequately inspected for harmful chemicals and elements. Such standards not only apply to industrial wastewaters but also boiler and cooling water treatments.
AOS Treatment Solutions
AOS Treatment Solutions is an industry leader in wastewater treatments and services. Since 1999, we have provided groundwater treatment services for a range of municipalities. With unsurpassed knowledge and expertise, our water treatment consultants have the tools and experience to treat all types of ground and surface water, including the collection of water samples, along with providing extensive testing to resolve water supply problems.
With the latest equipment and testing methods, AOS is committed to excellence in all DAF services and solutions. For more information, contact us today and get the results you deserve.