Dissolved gas flotation (DGF) is a widely used process in wastewater treatment and oil and gas industries to remove suspended solids and oil droplets from water. The composition of DGF involves several key components, each playing a crucial role in the process.

1. Dissolved gas: The first and most important component is the dissolved gas, usually air or nitrogen. The gas is dissolved under pressure in the water, forming tiny bubbles. These bubbles attach to the suspended solids or oil droplets, making them float to the surface for removal.

2. Pressure vessel: The pressure vessel is a crucial part of the DGF system. It is designed to hold the water and dissolved gas under high pressure, allowing for efficient dissolution of gas into the liquid. The pressure vessel also helps in controlling the release of dissolved gas when the pressure is reduced, forming bubbles.

3. Release mechanism: The release mechanism is responsible for releasing the pressurized water and dissolved gas from the pressure vessel into a flotation tank. This sudden release of pressure causes the dissolved gas to come out of solution and form bubbles, which attach to the suspended solids or oil droplets.

4. Flotation tank: The flotation tank is where the separation process occurs. The water and gas mixture from the pressure vessel is introduced into the flotation tank, where the bubbles attach to the suspended solids or oil droplets, causing them to rise to the surface. The solids or oil can then be skimmed off or collected for further treatment.

5. Skimming mechanism: The skimming mechanism is used to remove the floated solids or oil from the surface of the flotation tank. It typically consists of a rotating scraper or a skimming device that collects the floating material and transfers it to a separate collection system.