CDFU Technology Explained: How Cyclones and Micro-Bubbles Achieve Efficient Oil-Water Separation
In modern industrial wastewater treatment, fast and efficient separation technology is essential. The CDFU cyclonic dissolved gas flotation oil-removal unit, whose full English name is Cyclonic Dissolved Gas Flotation Unit, integrates ultra-fine bubble generation, dissolved gas flotation and cyclonic separation, and offers an innovative solution for removing free oil, emulsified oil and suspended solids from wastewater.
Core working principle
The CDFU process is a highly efficient, coordinated physical separation process built around three key stages.
Stage 1: generation and release of micro-bubbles. Air is forced into water under pressure to form saturated dissolved-gas water. When the pressure is released abruptly, the dissolved gas comes out of solution and generates a large, dense and stable population of micro-bubbles typically 5 to 30 microns in diameter. These ultra-fine bubbles have a large specific surface area and strong interfacial activity.
Stage 2: efficient attachment of bubbles to pollutants. Oily wastewater entering the unit is thoroughly mixed with the released micro-bubbles. As the bubbles rise slowly they collide with dispersed oil droplets and suspended particles and adhere firmly to them, forming bubble-oil droplet aggregates whose overall density is lower than that of water.
Stage 3: cyclone-enhanced separation. The mixture enters tangentially along the vessel wall and forms a high-speed swirling field. Centrifugal force drives the micro-bubbles and fine emulsified oil droplets rapidly towards the central region, where they further coalesce and grow. The bubble clusters carrying pollutants rise faster to the liquid surface and form a scum layer, which is finally discharged from the system by automatic control.
Through the dual enhancement of micro-bubble attachment and cyclonic centrifugation, the technology greatly improves separation efficiency and speed, achieving results that a single conventional technique struggles to match.
