Dissolved air flotation (DAF) is the water treatment process that clears wastewater by removing unwanted particles such as oil or other suspended solids. In the DAF system, water waste is treated by mixing air with wastewater under some pressure and then releasing that pressure in the flotation tank. This is one of the best and most effective treatments for wastewater treatment. DAF can be installed after some treatment, depending on the type of filtration process.
Parts of the Dissolved Air Flotation :
- Top Skimmer System
- Bottom Skimmer System
- Effluent Discharge Chamber
- Flotation Cell
- Flots (skimmings)
- air saturation system
- Contact Chamber
Process of DAF (Dissolved Air Flotation):
In the process of dissolving air flotation, wastewater is recycled through recycling pumps, passing through the air compressor to the air drum and then into the float tank again. Effluent water is pumped to the small vessel, in which air pressure is maintained with the help of an air compressor, which helps in the saturation of pressurized water with air. The coagulants like ferric chloride and aluminum sulfate are added to form tiny particles into big particles by adding them to small vessels.
Dissolved Air Flotation: Advantages and Applications
- Effluent water is pumped to the small vessel, in which air pressure is maintained with the help of an air compressor, which helps in the saturation of pressurized water with air
- A continuous system of removing wastewater from the same wall
- Inspection window for checking the floatation
- Automatic control system
- Extended retention times give better effluent quality.
- Designed for low velocity to achieve better separation
Dissolved air flotation is also used for the treatment of wastewater in other industries, including the oil industry, chemical plants, natural gas processing plants, general water treatment, paper mills, and the textile industry.
- Natural-gas processing is a wide industry whose primary purpose is to purify raw natural gas by removing impurities. In this process, a lot of water and waste are generated, and this wastewater is treated by the DAF system. Because of this, we can use the Dissolved Air Flotation system in a natural-gas processing plant.
- Paper Mills: In this type of industry, they waste more water in washing the paper in the machines for paperwork; this wastewater can be used by treating this water in sewage treatment plants. In this type of industry, we can use the Dissolved Air Flotation (DAF) System. This ideal solution is for optimizing the recovery of wastewater.
- Textile Industry: In this industry, lots of water is wasted by making the dyes for the fabrics and also in the washing of the products from which they were made. To control this, we can use a dissolving air flotation (DAF) system. With this, we can reuse the water that is wasted by the manufacturing process.
- General Water Treatment: In this context, reusing the treated water from general water treatment can be used in residential, commercial, and industrial applications. People waste lots of water in their daily routines, such as bathing and washing their clothes, and also through the use of water here and there. In this way, we can use dissolving air flotation in society, towns, or cities, and with the help of this, we can reuse that type of water again.
- Chemical Plants: The wastewater from this industry is usually very high and may also be a toxic pollutant and have an unpleasant odor. This water can waste from the construction of the chemical factory and also from making shoes. We can treat this water waste by using a dissolved air flotation system in chemical factories. The DAF system cleans wastewater using a dissolved air-in-water solution and a wastewater recycling process. Clarity of the effluent is improved through the addition of air, which aids in reducing the biological oxygen demand occurring in biological filters.
Features of Kelvin DAF :
- Customized models are available.
- Designed for low velocity
- Maximum and easy removal of waste particles
- easy installation process and long life
- High temperature and pH tolerance
What points to the DAF works:
- separate solid particles from wastewater
- remove oil particles in water
- Treated water meet discharge regulations
- Removal of TSS( Total Suspended Solids)
- Recovery of water & its reuse
- The biological treatment system downstream is reduced with the help of pretreatment.
- Removal of BOD(Biological Oxygen Demand) & COD( Chemical Oxygen Demand)
- The slurry formed inside tanks/settler tanks is thickened.