The 4-in-1 Synergistic Powerhouse: How SINOKLE’s CDFU Achieves Up to 99.97% Oil Removal Without Chemical Dosing
In the industrial wastewater treatment sector, peers know all too well that a single technology can never tackle complex water qualities on its own. High-efficiency equipment capable of truly holding its ground on-site is inevitably the result of multi-technology synergy. Today, let us break down the four core technologies of SINOKLE's CDFU Cyclone Dissolved Gas Flotation unit one by one, clarifying what each does and how they work in harmony.
1. Cyclonic Centrifugal Separation — The Mainstay of Coarse Separation
Oily wastewater enters the CDFU vessel at high speed via a tangential inlet, forming a powerful cyclonic flow field within the cylindrical chamber. Leveraging the density differential between oil and water (oil ~ 0.8–0.95 g/cm³, water ~ 1.0 g/cm³), centrifugal force pushes the lower-density oil droplets toward the center of rotation to form an oil core, while the heavier clean water moves outward against the vessel wall.
This process accomplishes the separation of most free oil droplets within seconds to tens of seconds, serving as the system's first high-efficiency "coarse filtration" barrier. Another critical function of cyclonic separation is creating a fully turbulent mixing environment for subsequent bubble contact—rather than a stagnant pool, it provides dynamic contact within a high-speed rotation, yielding a collision probability far higher than that of DAF under static conditions.
2. Ultra-Micro Bubble Generation — The Killer Weapon Against Emulsified Oil
This is the core stage where CDFU creates a generational gap over traditional flotation. Gas release in conventional DAF generates bubble sizes mostly in the 50–100 μm range. In contrast, CDFU utilizes SINOKLE's self-developed new-generation micro-bubble generation technology to control bubble size down to much smaller nano-to-micron levels.
Why are smaller bubbles better? Because for a given gas volume, smaller bubble diameters result in a larger total surface area (specific surface area is inversely proportional to particle size), expanding the contact area with emulsified oil droplets in water. Simultaneously, micro-bubbles rise more slowly and remain in the water longer, dramatically increasing the probability of oil droplet-bubble collision and adhesion. To use an analogy: catching fish with a coarse net lets small fish escape; switching to a fine sand filter leaves nothing behind—ultra-micro bubbles are that "fine sand net."
3. Dissolved Gas Flotation — The Classic Separation Driving Force
Dissolved gas flotation constitutes the foundational framework of the entire system. In the CDFU, a portion of the treated effluent is pressurized to 0.3–0.6 MPa and injected with compressed air or nitrogen to create supersaturated dissolved-gas water, which is then depressurized and released inside the vessel via dedicated releasers.
The essence of this process lies in controlling two links: "dissolution" and "release." Dissolution efficiency determines the total volume of available bubbles, while the releaser structure determines the uniformity of bubble size distribution. SINOKLE has patented and optimized both links, making CDFU's dissolved gas utilization rate significantly higher than that of traditional DAF, with lower energy consumption at equivalent treatment capacities.
4. Coalescence Demulsification — Forcing "Stubborn Pollutants" to Group Together
A considerable proportion of oil in industrial wastewater exists in an emulsified state—oil droplet surfaces are wrapped by surfactants to form stable oil-in-water (O/W) emulsions that struggle to aggregate due to inter-particle electrostatic repulsion.
Coalescence demulsification technology uses specialized internal components or media to cause emulsified oil droplets to collide and merge as they flow through, transforming small oil droplets into larger ones that are more easily captured by cyclonic centrifugal forces or adhered to by bubbles. While appearing auxiliary, this step is actually the critical leap that pushes oil removal efficiency from "90%+" to "99%+." Without demulsification, even the finest bubbles remain powerless against emulsified oil droplets protected by charge barriers.
The Logic of 4-in-1 Synergy
These four technologies are not simply chained in series; they are spatially nested and functionally complementary. Cyclonic flow provides the centrifugal force field and mixing dynamics, coalescence enlarges emulsified oil droplets, ultra-micro bubbles offer a massive "capture surface," and dissolved gas flotation provides the bubble source and flotation driving force. All four mechanisms occur simultaneously within a single enclosed vessel, mutually reinforcing one another.
Engineering field data validates the effectiveness of this synergistic logic:
· Petrochemical project in Shandong: Influent oil content of 250,000 mg/L, effluent < 150 mg/L (99.9% removal rate).
· Super-heavy crude project: Influent oil content of 150,000 mg/L, effluent < 40 mg/L (99.97% removal rate).
· Heavy fuel oil power plant projects in Sierra Leone and Bangladesh: Effluent oil contents kept below 5 mg/L and 10 mg/L, respectively.
· Scalability: Full coverage across treatment capacities from 5 to 250 m³/h demonstrates that this synergistic architecture maintains exceptional stability during scale-up.
Technical Summary
In essence, CDFU operates within a compact, enclosed space to tackle "large masses" with cyclonic centrifugation, dismantle "stubborn pollutants" with coalescence demulsification, encircle "escaped particles" with ultra-micro bubbles, and perform final conveyance with dissolved gas flotation. Four simultaneous approaches, purely physical, with zero chemical dosing throughout. Considering the operating data from actual engineering projects, the competitiveness of this technical route in industrial oily wastewater treatment requires no additional commentary.
