english Dissolved Gas Flotation (DGF) is a water treatment process that removes suspended solids, oils, and other contaminants by introducing microbubbles to attach and float particles to the surface. The efficiency of DGF relies on several core components:
1. Pressure Dissolution Tank (Saturation Vessel)
-
A pressurized vessel where air or gas (typically nitrogen or recycled gas) is dissolved into water under high pressure (3–5 bar).
-
Creates a supersaturated solution that releases microbubbles when depressurized.
2. Release Valve (Pressure Reduction Valve)
-
Rapidly reduces pressure to form 20–100 micron microbubbles, crucial for effective particle attachment.
-
Ensures uniform bubble distribution in the flotation chamber.
3. Flotation Tank (Separation Chamber)
-
Where microbubbles attach to contaminants, forming a floating sludge layer (float).
-
Equipped with skimmers or scrapers to remove floated solids.
4. Recycle Pump
-
Recirculates treated water back to the saturation vessel to maintain gas dissolution efficiency (typically 20–50% recycle rate).
5. Effluent & Treated Water Outlet
-
Clarified water exits from the bottom, while surface sludge is removed for further treatment.
6. Chemical Dosing System (Optional)
-
Adds coagulants (e.g., alum, polymers) to enhance particle aggregation and bubble adhesion.
7. Control Panel & Sensors
-
Monitors pressure, flow rates, and bubble size for optimized performance.
